PAH, PCB and OCP concentrations in the sediments, local mussels, transplanted mussels and passive samplers in the İstanbul Strait and Marmara Sea, Turkey O. S. Okay1, B.Karacık1, B. Henkelman2, K-W.Schramm2,3

1Istanbul Technical University, Faculty of Naval Architecture and Ocean Engineering, 34469, Maslak, İstanbul, Turkey 2Helmholtz Zentrum München, Research Center for Environmental Health, Institute of Ecological Chemistry, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany 3TUM, Wissenschaftszentrum Weihenstephan für Ernährung und Landnutzung, Department für Biowissenschaften, Weihenstephaner Steig 23, 85350 Freising, Germany

E-mail contact: [email protected]

1. Introduction Polycyclic aromatic hydrocarbons (PAHs) and persistent organic pollutants (POPs) are accumulated in several matrices of the aquatic environments and have several negative effects on the organisms [1] Most lipophilic anthropogenic organics tend to be associated to the suspended particles in the water column due to their low solubility and accumulate in the sediments [2]. They also accumulate in fish and shell fish especially in mussels and may lead to serious human health hazards [3]. In this study, the surface sediments and mussels were collected from and transplanted mussels and passive samplers (SPMDs and butyl rubber sorbents; BRs) were deployed to the five sites in the İstanbul Strait and Marmara Sea. The samples were then analyzed for PAHs, polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs). The results of the analysis for several matrices were compared. The previous monitoring studies carried out in the İstanbul Strait ecosystem showed that it was contaminated by those pollutants [4,5]. The Strait is a part of the Turkish Strait system connecting the Black Sea to the Medditerranean and one of the busiest waterways in the world. Passive samplers have been developed to monitor organic pollutants and frequently used in several monitoring studies. Lipid-containing semipermeable membrane devices (SPMDs) have been most commonly utilized as passive samplers. Butyl rubber sorbents synthesized to remove the organic pollutants and oil spills from the aquatic environments were used in this study as a passive sampler and the efficiency of the sorbents were compared with the SPMDs [6].

2. Materials and methods Surface sediments (0-10 cm) and mussels (Mytilus galloprovincialis; 4-5 cm) were collected from five coastal stations in the Istanbul strait and Marmara Sea and transferred to the laboratory in foam boxes filled with ice. Mussels were dissected in the laboratory, and transferred into the vials. Samples were frozen at - 20oC until analysis. SPMDs were prepared from 29 cm x 2.5 cm low-density polyethylene lay- flat (LDPE) tubing (VWR Ismaning, Germany) with a membrane thickness of approximately 65 µm. The triolein- containing part of the sampler - excluding the mounting loops- has a surface area of 115 cm2. 700 µL of triolein (Sigma, Munich, Germany, 99 %) was spiked with performance reference compounds The prepared SPMDs were stored in closely aluminum sealed heat cleaned 10 mL glass vials, further stored at -20 oC and kept cooled during transportation until deployment. SPMDs, butyl rubber sorbents and mussels were deployed with specially designed stainles steel cages and in nets respectively. The samplers and mussels were retrieved from the sites after 7 and 21 days of deployment, carried to the laboratory and stored at - 20oC until analysis. After extraction and clean-up processes, the samples were analyzed with a high resolution mass spectrometer Finnigan MAT 95S (Thermo Electron GmbH, Bremen, Germany) coupled with an Agilent GC 6890 (Agilent Technologies, Palo Alto, CA, USA).

3. Results and discussion Maximum sediment T-PAH concentration was measured at site 24 (6431 ng/g). This site is situated at the coast of the main shipyard area of Turkey. Local mussels at sites 12 and 24 do not exist. Among the other sampling sites, the highest mussel T-PAH concentration (201 ng/g) was determined at site 6a which is the mouth of a creek entering site 6. The local and transplanted mussels have nearly the same T-PAH concentrations both after 7 and 21 days of deployment. However, passive samplers have higher T-PAH concentrations. The lower amounts of T-PAH concentrations in mussels compared to the passive samplers show that T-PAHs could be metabolized by the mussels. The T-PAH values of the passive samplers after 21 days of deployment were higher compared to the values measured after 21 days of deployment. The maximum sediment (25602 ng/g) and local mussel (881 ng/g) T-PCB concentrations were measured at site 6. In general, the differences in the concentrations of the local mussel, transplanted mussels and passive samplers were not significant. This shows that the PCB compounds could not be metabolized as the PAH compounds by the mussels. The accumulation of PCBs by the BR sorbents were not efficient as in case of PAHs. When SPMDs and BR sorbents were compared, the accumulation of PCB congeners in SPMDs were found much higher compared to the BR sorbents. Among the PCBs, the indicator PCBs were the dominant congeners in all matrices. The percentage of indicator PCBs were different in sediments and mussels. For example at site 6, the percentage of indicator PCBs were 80%, whereas that value was 90% in sediments. None of the non-ortho and mono-ortho PCB congeners were measured at site 12 which is one of the pristine sites in the Strait situated at the Black Sea entrance. OCP concentrations were only measured in sediments (113974 ng/g) and transplanted mussels (7 days: 14370 ng/g and 21 days: 38261 ng/g). The highest concentrations were measured at site 24. The most dominant OCP compounds were HCH and DDT derivatives. DDT concentrations in sediments were higher compared to the concentrations in mussels.

4. Conclusions

The results of the study show that some of the sites in the Strait are highly polluted by the analyzed pollutants and especially the levels in the mussels may be hazordous for the human health. The necessary precautions should be taken for mussel consumption from those contaminated areas. The compared efficiencies of passive samplers indicate that BR sorbents may also be used as passive samplers for PAHs.

5. References [1] Kolonkaya D. 2006. Organochlorine pesticide reidues and their toxic effects on the environment and organisms in Turkey, Intern. J. Environ. Anal. Chem 86:147-160. [2] Hong SH, Yim UH, Shim WJ, Li DH, Oh JR. 2006. Nationwide monitoring of polychlorinated biphenyls and organochlorine pesticides in sediments from coastal environment of Korea, Chemosphere 64:1479- 1488. [3] Yang N, Matsuda M, Kawano M, Wakimoto T. 2006. PCBs and organochlorine pesticides (OCPs) in edible fish and shellfish from China, Chemosphere 63:1342-1352. [4] Karacık B, Okay OS, Henkelmann B, Bernhöft S, Schramm K-W. 2009. Polycyclic aromatic hydrocarbons and effects on marine organisms in the Istanbul strait. Environ Int 35:599-606. [5] Okay OS, Karacık B, Henkelmann B, Bernhöft S, Schramm K-W. 2009. PCB and PCDD/F in sediments and mussels of the Istanbul Strait (Turkey). Chemosphere 76:159-166. [6]Ceylan D, Doğu S, Karacık B, Yakan S, Okay OS, Okay O. 2009. Evaluation of butyl rubber as sorbent material for the removal of oil and polycyclic aromatic hydrocarbons from seawater. Environ Sci Technol 43:3846-3852.

Acknowledgement - This research has been supported by The Scientific and Technological Research Council of Turkey (TÜBİTAK) and International Bureau of the Federal Ministry of Education and Research, Germany through a Joint Research Project (Project nos: 106Y302 in Turkey and TUR 06/007 in Germany)

Equilibrium Sampling of Environmental Pollutants in Baltic Sea Sediment along a Transect in the Stockholm Archipelago

Annika Jahnke1, Philipp Mayer2 and Michael S. McLachlan1

1 Department of Applied Environmental Science (ITM), Stockholm University, SE-10691 Stockholm, Sweden 2 Department of Environmental Science, Aarhus University, DK-4000 Roskilde, Denmark E-mail contact: [email protected]

1. Introduction

The determination of the fugacity, freely dissolved concentration (Cfree) or chemical activity of environmental pollutants in sediment is important since sediment is the dominant exposure medium for bottom-dwelling organisms and therefore is particularly relevant in a bioaccumulation context. Further, sediment represents a reservoir for numerous hydrophobic organic chemicals (HOCs) in the aquatic environment, and the chemical activity in the sediment can govern the chemical activity in the water column. Especially the small-grained material often has a high storage capacity for HOCs due to its large fraction of organic carbon (OC). We differentiate between accumulation (A) sediment with >75% water content and high fractions of OC and thus pollutants and erosion/transport (E/T) sediment with lower water content that often is relatively coarse with lower percentages of OC and pollutants.

To measure Cfree of HOCs such as polychlorinated biphenyls (PCBs), a polymer is brought into contact with the sediment and removed after equilibrium between the two phases has been established. The silicone rubber polydimethylsiloxane (PDMS) is an all-round sampling phase that can be applied in complex matrices [1]. Here we used a coated glass jar method [2,3].

The aim of this study was to investigate Cfree of PCBs in paired A and E/T sediment samples from the Baltic Sea, collected along a gradient from central Stockholm towards the middle of the Stockholm archipelago. Since numerous HOCs including PCBs were banned almost four decades ago, a relatively homogenous distribution of Cfree was expected whereas the concentrations in sediment were expected to vary more due to the spatial heterogenity of the sediment composition. In this work we studied (i) the applicability of the coated glass jar method in the open Baltic Sea, (ii) the change in Cfree with increasing distance from the urban center, (iii) differences in Cfree between A and E/T sediments, (iv) the gradient between Cfree of PCBs in the sediments (this study) compared to available Cfree data in the water column, (v) how calculated equilibrium partitioning concentrations in biota lipids (CLipid) compare with monitoring data of lipid normalised concentrations in biota determined by whole organism extraction, and (vi) how Kd values determined as part of this study compare with Kd values in the literature.

2. Materials and methods

Glass jars [2,3] with very thin PDMS coatings on the vertical inner walls were used to assess the Cfree of PCBs in Baltic Sea sediment. The method makes use of three different coating thicknesses (2 µm, 4 µm and 8 µm), which allows valid equilibrium sampling to be confirmed for each sample and analyte (Figure 1), while at the same time verifying the absence of sampling artefacts.

Figure 1: Glass jars internally coated with thin PDMS-layers of different thicknesses allow for a built-in quality assurance. An extensive method validation was done using surface sediments from the middle Stockholm archipelago. Based on these results, a sampling campaign from central Stockholm out into the middle Stockholm archipelago was carried out where paired sediment samples (A and E/T sediments) were collected at 7 additional stations. In addition to the equilibrium sampling, a traditional exhaustive extraction of the sediment samples was carried out.

3. Results and discussion Plotting the mass of PCBs sampled in the PDMS versus the mass of PDMS in the coated jars revealed proportionality (Figure 2) which confirms that equilibrium had been established. Further, Figure 2 verifies artefact-free sampling in A and E/T sediment at low blank levels. Using the coated glass jar method, it could be shown that there is a gradient in Cfree of PCBs from the urban sites towards the outer archipelago. This indicates that the Stockholm waters continue to be a source of PCBs to the Baltic Sea close to four decades after the PCB ban in the 1970ies. The gradient could be caused by either ongoing releases to water or PCB residues in sediment from past emissions. In this study, half of the samples had similar Cfree in paired A and E/T sediments, whereas the other half showed differences of up to a factor of 3 (Figure 2).

Figure 2: Mass of sampled PCB versus mass of PDMS in A sediment (left) and E/T sediment (right) from Edöfjärden.

From the concentrations of PCBs in the PDMS, Cfree could be calculated using KPDMS,water [4]. CLipid were calculated using KLipid,PDMS [5] and compared to existing monitoring data. Additionally, Soxhlet extraction of the sediment samples was carried out along with total OC and soot carbon determination to allow for calculation of Kd values. Finally, the spatial distribution of Cfree and Kd values was examined.

4. Conclusions

Passive equilibrium sampling using coated glass jars was shown to be a convenient, accurate and sensitive technique to determine Cfree of PCBs in Baltic Sea sediments. Applying equilibrium sampling with PDMS is a powerful tool to assess bioaccumulation: Immersing the same sampling phase in biota and their relevant exposure medium (e.g., sediment, water or air) can give direct indications of whether biomagnification has occurred.

5. References [1] Jahnke A, Mayer P. 2010. Do complex matrices modify the sorptive properties of polydimethylsiloxane (PDMS) for non-polar organic chemicals? J Chromatogr A 1217: 4765-4770. [2] Reichenberg F, Smedes F, Jönsson JÅ, Mayer P. 2008. Determining the chemical activity of hydrophobic organic compounds in soil using polymer coated vials. Chem Cent J 2, 8. [3] Mäenpää K, Leppänen MT, Reichenberg F, Figueiredo K, Mayer P. 2011. Equilibrium Sampling of Persistent and Bioaccumulative Compounds in Soil and Sediment: Comparison of Two Approaches To Determine Equilibrium Partitioning Concentrations in Lipids. Environ Sci Technol 45:1041-1047. [4] Smedes F, Geertsma RW, van der Zande T, Booij K. 2009. Polymer-Water Partition Coefficients of Hydrophobic Compounds for Passive Sampling: Application of Cosolvent Models for Validation. Environ Sci Technol 43:7047-7054. [5] Jahnke A, McLachlan MS, Mayer P. 2008. Equilibrium sampling: Partitioning of organochlorine compounds from lipids into polydimethylsiloxane. Chemosphere 73:1575-1581.

Acknowledgement - We thank Urs Berger for sampling assistance, Charlotte Dahl Schiødt for the coating of the glass jars, Kerstin Grunder for laboratory assistance, Yngve Zebühr and Cecilia Bandh for the high- resolution GC/MS analyses, Örjan Gustafsson’s group for help with the soot carbon analysis and Heike Siegmund for the total OC analyses. This research was funded by the Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (FORMAS, 216-2005-1200) and the EU Commission (OSIRIS, GOCE-037017; Marie Curie Intra European Fellowship, PIEF-GA-2008-219675). Effects of flow velocity and calibration conditions on a passive sampler for perfluorinated alkyl carboxylates and sulfonates in water

Sarit L. Kaserzona, Etienne L.M. Vermeirssenb, Darryl W. Hawkerc, Karen Kennedyd, Jack Thompsone, Christie C. Bentleya, Kees Booijf and Jochen F. Muellera aThe University of Queensland, The National Research Centre for Environmental Toxicology (Entox), 39 Kessels Rd., Coopers Plains QLD 4108, Australia bEawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dubendorf, Switzerland cGriffith University, School of Environment, Nathan QLD 4111, Australia dDepartment of Environment and Resource Management, Ecosciences Precinct, 41 Boggo Rd, Dutton Park QLD 4102 eQueensland Health Forensic and Scientific Services, Coopers Plains QLD 4108, Australia fNIOZ Royal Netherlands Institute for Sea Research, P.O. Box 59, 1790 AB Texel, The Netherlands E-mail contact: [email protected] ______

1. Introduction

Perfluorinated chemicals (PFCs) are emerging environmental contaminants with a global distribution. Due to the moderate water solubility of some PFCs, the majority of the environmental burden is in the water phase. Multiple studies have shown that PFCs are not effectively removed in waste-water treatment plants (WWTPs) and in some instances are enriched in the effluent. This makes WWTP outfalls potential point sources in the environment. This tendency to pass through water treatment also extends to drinking water treatment and numerous studies have found low level (ng L-1) concentrations in municipal drinking waters. Passive sampling provides a low cost and time integrative sampling approach that has already proven useful for a broad range of environmental contaminants. A newly developed and validated Polar Organic Chemical Integrative Sampler (POCIS) with a weak anion exchange sorbent has shown potential as a passive sampler for PFCs in water. However more work was required to further validate the sampler. The aim of this work was to evaluate the influence of water flow rate and calibration conditions on the uptake of PFCs into POCIS sampler.

2. Experimental approaches

Passive samplers were constructed using polar organic chemical integrative samplers (POCIS) based on Alvarez et al.[1] with modification. In this design two 0.45 µm membranes (47 mm, PALL Australia) enclosed 600 mg of Strata X-AW sorbent (Phenomenex, Australia) with a total exchangeable surface area of 16 cm2. PFCs investigated in this work were perfluorohexanoate (PFHxA), perfluoropentanoate (PFPeA) perfluoroheptanoate (PFHpA), perfluorooctanoate (PFOA), perfluorononanoate (PFNA) and perfluorodecanoate (PFDA), perfluorobutanesulfonate (PFBS), perfluorooctanesulfonate (PFOS) and perfluoroundecanoic acid (PFUnDA). Flow-controlled experiments were conducted with POCIS deployed in channel systems through which river water fortified with PFCs (250 - 350 ng L-1) flowed at rates between 2.6 and 37 cm s-1. POCIS samplers were exposed in time series for 1 (x3), 2, 3, 4, 6, 9, 12 and 15 d. Composite daily grab samples were collected on each day and temperature, salinity and pH were recorded. Samples were analysed by LC-MS (Thompson et al.[2]). Data was compared with a previous study conducted in tap water with different temperature, salinity, pH and flow velocity conditions.

3. Outcomes

• Water flow rates did not have a significant effect on the uptake kinetics and sampling rates of PFCs into POCIS from this study.

• Using the water concentrations (Cw) obtained via grab sampling and the amount in the passive samplers (Ns), sampling rates (Rs) for the PFCs were approximated. Under the experimental -1 conditions employed, the Rs range for PFCs was between 0.09 – 0.27 L day .

• Overall good agreement was observed between sampling rates obtained from passive sampler calibration in this study and data obtained from a previous calibration study despite differences in flow velocity, temperature, salinity and pH. Further investigation is necessary however to assess the effect of specific environmental factors on sampling kinetics.

4. Conclusion

Uptake kinetics and sampling rates for PFCs did not vary significantly with flow velocity. Sampling rates derived (0.08 – 0.28 L.day-1) are comparable to sampling rates determined in a previous study under different conditions. A passive sampler for PFC and similar compounds could help elucidate potential aquatic exposure routes to PFCs.

5. Research direction

- Sensitivity of this passive sampler and its application for additional anionic species and other hydrophilic compounds has begun and requires further investigation.

6. References

1. Alvarez, D.A., et al., Development of a passive, in situ, integrative sampler for hydrophilic organic contaminants in aquatic environments. Environmental Toxicology and Chemistry, 2004. 23(7): p. 1640-1648. 2. Thompson, J., G. Eaglesham, and J. Mueller, Concentrations of PFOS, PFOA and other perfluorinated alkyl acids in Australian drinking water. Chemosphere, 2011. 83: p. 1320-1325.

Occurrence and fate of brominated and organophosphorus flame retardants in river water

Joyce Cristale1, Athanasios Katsoyiannis 2, Chang’er Chen2, Andrew J. Sweetman2, Kevin C. Jones2, Silvia Lacorte1

1Dept.of Environmental Chemistry, IDAEA-CSIC, Jordi Girona 18-26, 08034 Barcelona, Catalonia, Spain 2Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK E-mail contact: [email protected]

1. Introduction The use of alternative flame retardants (FRs) increased rapidly after the ban of polybrominated diphenylethers (PBDEs). Alternative FRs include organophosphorus and new brominated FRs. These pollutants are widespread in the environment and due to their toxicity, much concern is given on their environmental distribution and fate. The presence of these contaminants has been studied in biotic and abiotic samples [1,2], while few data is avalaible about their occurrence in waters. Some studies identify wastewater treatment plants (WWTP) as an important source for some of these contaminants due to the limited removal efficiencies of conventional WWTPs [3], while little is known about the dynamic of distribution of these contaminants along rivers. The aim of this work was to study the occurrence and fate of a wide range of flame retardants in river waters, including PBDEs (BDE 28, 47, 99, 100, 153, 154, 183 and 209), new brominated flame retardants (hexabromobenzene - HBB, pentabromoethyl benzene - PBEB, pentabromotoluene - PBT, 2,3-dibromopropyl 2,4,6 tribromophenyl ether - DPTE, 2-ethylhexyl 2,3,4,5 tetrabromobenzoate - EHTBB, Bis(2-ethyl-1-hexyl)tetrabromo phtalate – BEHTBP, 1,2 bis (2,4,6 tribromophenoxy)ethane – BTBPE, and decabromodiphenyl ethane - DBDPE) and organophosphorus flame retardants (tris(2-choroethyl) phosphate - TCEP, tris(2-chloro-1-methylethyl) phosphate - TCPP, tris[2-chloro- 1-(chloromethyl)ethyl] phosphate – TDCP and triphenylphosphate - TPhP). As a first step, a novel passive sampler for the simultaneous analysis of polar and non-polar flame retardants was tested and calibrated in the laboratory. In a second step, a monitoring study was performed along the River Aire, in Yorkshire, Northeastern England using grab samples and the passive sampler.

2. Materials and methods 2.5 L of river water were collected from each of the 13 points along the River Aire during a one-day sampling campaign. The sampling points include a site near the river source, and before and after WWTPs, covering an extension of >100 km. 500 mL of unfiltered water sample was spiked with labelled surrogate (MHBB, MBDE 77, BDE 209) and extracted using HLB 200 mg (WATERS, USA) cartridges. The samples were eluted with 15 mL of dichloromethane/hexane (1:1) and dichloromethane/acetone (1:1), concentrated by N 2 flow until almost dry and reconstituted in 100 uL of hexane. Blanks (MilliQ water) and spiked MilliQ and river water samples (two levels) were used for quality control. The analysis was performed by means of GC- EI-MS. The performance of the ceramic dosimeter® passive sampler filled with 400 mg of HLB sorbent (Sigma Aldrich) was tested in laboratory conditions using spiked water at 20 ng mL-1 for TCEP, TCPP, TDCP, TPhP, and 1 ng mL-1 for HBB and PBEB. To calibrate the system, the passive samplers were deployed during 2, 4, 6, 8 and 10 days, with continuous stirring. In field sampling, 6 samplers were deployed at River Aire in a point located about 400 m downstream from a WWTP. Two samples of 2.5 L of water were collected after the passive sampling deployment, and simultaneously with passive sampling collection after 1, 3, and 5 weeks. The water samples were extracted as described above. The passive sampler was extracted with 15 mL of acetone and 15 mL of dichloromethane/hexane 1:1. The extract was concentrated under a gentle stream of N2 flow to almost dryness and reconstituted in 100 uL of hexane. The analysis was performed by GC-EI-MS.

3. Results and discussion

3.1. River Aire results The analytical protocol of spiked MilliQ and river water was satisfactory, with average recoveries ranging from 81 to 112 % with RSD ≤ 10% for organophosphorus flame retardantes, average recoveries from 63 to 119 % with RSD ≤ 18% for new brominated flame retardants and finally average recoveries from 47 to 107 % with RSD ≤ 16% for PBDEs. For the water samples, the surrogate average recoveries were 92 ± 23% for MHBB, 105 ± 21 % MBDE 77 and 60 ± 20 % for MBDE 209. TCPP and TPhP were detected in procedual blanks at 15.5 ± 1.3 and 3.5 ± 0.3 ng L-1, and these contributions were substracted from the water results. The limits of quantification of the method ranged from 0.04 to 2.4 ng L-1 for organophosphorus flame retardants, from 0.08 to 104 ng L-1 for new brominated flame retardants and from 0.2 to 2.5 ng L-1 for PBDEs. Organophosphorus flame retardants were detected in most of the river water samples. TCPP was the most abundant compound, detected in all samples, ranging from 0.11 to 26 µg L-1 (average 8.3 µg L-1). TCEP, TDCP and TPhP were detected in 11 sampling points ranging from 0.12 to 0.32 µg L-1, 0.06 to 0.15 µg L-1 and 0.006 to 0.02 µg L-1, respectively. From the brominated flame retardants, the BDE 209 was the most detected compount, present in 11 sampled sites, ranging from 0.02 to 0.29 µg L-1. PBEB and HBB were seldom detected, at concentrations from 0.16 to 0.40 ng L-1 (n = 5) and 0.76 ng L-1 (n = 1), respectively.

3.2. Passive sampling results Figure 1 (a) presents the accumulated masses using the passive sampler for organophosphorus flame retardants. The sampling rate obtained for TCPP, TCEP, TDCP and TPhP were 2.4, 2.9, 2.3 and 2.1 mL day- 1, respectively. The sampling rate for HBB and PBEB were of 0.4 and 0.6 mL day-1, respectively. The passive sampler was deployed in river water for 1, 3, and 5 weeks, and the accumulated mass is presented in Figure 1 (b, c). The accumulation rate decreased after 3 weeks while the external appearance of the 5-week deployed samplers indicate that biofouling interfered the sampling performance. The passive sampling derived pollutant concentrations in water were compared with the respective results obtained through grab sampling. Organophosphorus were detected in all water samples. Good correlation was observed between the concentrations of TCPP, TDCP, TDCP and TPhP determined by active sampling over the 5 weeks and the passive sampling, with concentrations within the same order of magnitude. Overall, the passive sampler ceramic dosimeter filled with HLB sorbent is a good alternative for water monitoring studies.

TCPP TCEP TDCP TPhP TCPP TCEP TDCPP TPhP 450 20 700 400 18 600 350 16 500 300 14 400 250 12 10 300 200 8 150 200 6 100 100 4

Accumulated mass (ng) 50

Accumulated mass (ng) 2

0 Accumulated mass (ng) 0 0 0 50 100 150 200 250 300 1 3 5 1 3 5 Time (hours) Weeks Weeks (a) (b) (c) Figure 1: Mass accumulation in laboratorial calibration (a) and in river water deployment (b, c) for the passive sampler device

4. Conclusions

Flame retardants were detected in River Aire waters (England) using a ceramic passive sampler filled with HLB, specifically designed for these families of contaminants. Deployment conditions were optimized and the system permits to accumulate organophosphorus flame retardants over a 3-week period, at concentrations similar to grab sampling. The detection of several flame retardants permitted to identify pollution sources and their transport and fate along a river system characterized by industrial and wastewater treatment plant discharges.

5. References [1] Covaci A, Harrad S, Abdallah MAE, Ali N, Law RJ, Herzke D, de Wit CA. 2011. Novel brominated flame retardants: A review of their analysis, environmental fate and behaviour. Environment International 37: 532-556. [2] Reemtsma T, García-López M, Rodríguez I, Quintana J.B., Rodil R. 2008. Organophosphorus flame retardants and plasticizers in water and air I. Occurrence and fate. TrAC - Trends in Analytical Chemistry 27: 727-737. [3] Meyer J, Bester K. 2004. Organophosphate flame retardants and plasticisers in wastewater treatment plants. Journal of Environmental Monitoring 6: 599-605.

Acknowledgement - The authors wish to thank Mark Earnshaw and Dr JianhuiTang for their assistance in the sample collection; Joyce Cristale acknowledges a FPI grant from the same Ministry (BES-2009-016460). The project was financed by Ministry of Education and Innovation of Spain, project CTM2008-03263/TECNO.

Porewater profiles of As, Se, Fe, Mn, V and P in spiked marine sediment measured using DGT and DET techniques

Price, Helen L.1; Teasdale, Peter R.2; Jolley, Dianne F.1

1 School of Chemistry, University of Wollongong, NSW 2522, Australia 2 Environmental Futures Centre, Griffith University Gold Coast Campus, QLD 4222, Australia

E-mail contact: [email protected]

1. Introduction Arsenic (As) and selenium (Se) have become increasingly significant in environmental chemistry because they are biologically toxic and present in natural waters at trace concentrations (nM). Within sediments precipitated contaminants such as As and Se are mobilised in the suboxic zone of the sediment with the reductive dissolution of iron and manganese (oxyhydr)oxides [1] acting as a source to porewaters and overlying waters and hence labile and a source for biological uptake.

The need for high resolution in situ techniques is becoming apparent due to a better understanding of heterogeneity within sediment [2]. The diffusive gradients in thin films (DGT) and diffusive equilibrium in thin films (DET) techniques are in situ techniques that have been used to measure trace element contaminants in sediments [3]. A ferrihydrite binding layer has been investigated for use with the DGT technique and was 3- found to quantitatively bind a variety of analytes including As(V), As(III), Se(IV), V(V), PO4 , [4-5]. Here we present a novel use of DGT and DET to compare the usefulness of precipitated ferrihydrite and Metsorb™ DGT binding gels for the simultaneous measurement labile Fe, Mn, As, Se, V and P in marine sediments.

2. Materials and methods

Sediment preparation and probe deployment Sediment collected from a marine mangrove was sieved, allocated into seven individual containers placed into a single large aquarium and aged under laboratory conditions for 8 months. Six sediments were spiked into the anoxic region of the sediments with solutions containing elevated concentrations of inorganic As and Se. The seventh container was an unspiked control. Fe, Mn, V or P were not included in the spike solutions, and natural levels were measured. Sediments were allowed to re-establish equilibrium after spiking for 48 hours at room temperature prior to deployment of DET and DGT probes. Sample analyses were conducted using ORC- ICP-MS using collision or reaction gases.

3. Results and discussion Profiles of V and P in aged marine sediments The profiles for V bound to ferrihydrite and Metsorb™ binding gels were in good agreement, with maximas of 24 to 38 nM occurring at about 10 mm depth. The - dominant aqueous species was most likely to be V(V) oxyanion as VO2(OH)2 , which quantitatively adsorbs to ferrihydrite in natural waters [5]. Below 25 mm, DGT-labile V concentrations decreased to <2 nM, likely due to V(V) undergoing redox transformation within the sub-oxic zone. The P measured by ferrihydrite DGT were more variable than Metsorb™, however, the mean DGT-labile P for ferrihydrite and Metsorb™ binding gels were in good agreement throughout the profile. The predominant dissolved orthophosphate species in - 2- marine systems (pH 5-9) are H2PO4 and HPO4 , and although Fe(II) minerals within the sediment have a high capacity for phosphate, they exhibit a relatively low affinity and are sensitive to changes in pH. This was shown by a trend for increasing DGT-labile phosphate below the oxic region of the sediment.

Profiles of spiked As and Se in aged marine sediments Profiles for arsenic bound to ferrihydrite and Metsorb™ binding gels were in good agreement for As(V) spiked sediment, but varied for As(III) in the suboxic/anoxic region. Both profiles show that the spike solutions had spread throughout the sediment, exhibiting very similar trends for both binding agents at the sediment-water interface, with the maxima occurring at or just above the sediment-water interface. Below the SWI the performance of ferrihydrite was consistently higher than Metsorb™, however these differences were <10 nM. There was significant DGT uptake of As in the suboxic and oxic regions of the sediments, above the redox boundary at 40 mm. DGT- labile Se was present in the spiking region between 40-80 mm (Fig 1 a,c), however lower concentrations were observed in Se(VI) spiked sediments, as Se(VI) has a low affinity to both ferrihydrite and Metsorb™ in seawater matrices [5,6]. DGT-labile Se was also present in the upper 10 mm of the sediments and overlying waters of both spiked sediments, indicating that some of the Se(VI) was transformed to a DGT-labile form, most likely reduced to Se(IV) which is the dominant dissolved Se species in moderately reducing conditions [7]. DET profiles of Se were markedly different between the two sediments types (Fig 1 b,d). Se(VI) spiked sediments had two regions of elevated Se at 46-56 mm (~200 nM) and 62-66 mm (~ 800 nM), both within close proximity to the spike depth. The Se(IV) DETs showed significant Se throughout the profile.

(a) Se (b) Se (c) Se (d) Se 20 20 20 20

0 0 0 0

-20 -20 -20 -20 DGT - Ferri DGT - Ferri DET DET DGT - TiO2

pth ( mm) mm) pth ( -40 -40 -40 -40 De

-60 -60 -60 -60

-80 -80 -80 -80

-100 -100 -100 -100 0 500 1000 1500 0 100 200 300 0 800 1600 2400 0 600 1200 1800 -1 -1 n moles L n moles L-1 n moles L n moles L-1

Fig.1. DGT- and DET-labile selenium profiles in marine sediments spiked with 25 µM selenate (a, b). and selenite (c, d).

Profiles for V, P, As, Fe and Mn will be presented and discussed in detail at the conference.

4. Conclusions This study has confirmed the usefulness of both the precipitated ferrihydrite and Metsorb™ binding gels for the simultaneous measurement of As(III) and As(V) (as total As), Se(IV), and natural levels of V(V) and 3- PO4 from marine sediments. Similar porewater profiles were observed for both binding gels, verifying comparable affinities and capability for those analytes in marine sediment. The concurrent use of DET identified the Fe/Mn redox boundary at 40 mm below the sediment-water interface. The importance of dual DET and DGT deployments was highlighted by the high proportion of DET labile anions which were present in much lower concentrations on the DGT. These differences were attributed to redox-driven transformations within the suboxic and anoxic regions of the sediments, converting oxyanions to non-DGT labile forms.

5. References 1. Edenborn, H.M., et al., Observations on the diagenetic behaviour of arsenic in a deep coastal sediment. Biogeochemistry, 1986. 2(4): p. 359-376 2. Stockdale, A., W. Davison, and H. Zhang, Micro‐scale biogeochemical heterogeneity in sediments: A review of available technology and observed evidence. Earth-Science Reviews, 2009. 92: p. 81-97. 3. Davison, W., et al., eds. Dialysis, DET and DGT: in situ diffusional techniques for studying water, sediments and soils. In Situ Monitoring of Aquatic Systems –chemical analysis and speciation, ed. J. Buffle and G. Horvai. 2000, IUPAC,Wiley: Chichester. 495-569. 4. Stockdale, A., W. Davison, and H. Zhang, High‐resolution two‐dimensional quantitative analysis of phosphorus, vanadium and arsenic, and qualitative analysis of sulphide, in a freshwater sediment. Environ Chem, 2008. 5 p. 143-149. 5. Price, H., et al., Diffusive gradients in a thin film technique for measuring inorganic arsenic, selenium(IV), vanadium and phosphorus in fresh‐ and marine waters. Anal Chem, submitted. 6. Bennett, W.W., et al., New diffusive gradients in a thin film technique for measuring inorganic arsenic and selenium(IV) using a titanium dioxide based adsorbent. Anal Chem, 2010. 82(17): p. 7401-07. 7. Masschelyn, P.H., R.D. Delaune, and W.H. Patrick Jr., Transformations of selenium as affected by sediment oxidation‐reduction potential and pH Environ Sci. Technol., 1990. 24: p. 91‐96. Polar (un)charged micropollutants on SPE materials – Which factors control the adsorption?

Patrick S. Bäuerleina, Jodie E. Mansella, Steven T. J. Drogeb, Roberta C. H. M. Hofman-Carisa, Thomas L. ter Laaka and Pim de Voogta.

a KWR Watercycle Research Institute, Groningenhaven 7, 3433 PE Nieuwegein, The Netherlands Email contact: [email protected], [email protected] b Department of Analytical Environmental Chemistry, Helmholtz Centre for Environmental Research – UFZ Leipzig, Permoserstraße 15, 04318 Germany

1. Introduction

Adsorption of organic solutes from the water phase onto solid matter is a crucial process in the environment, water purification and in analytical science. The ability to adsorb to and absorb into a material dictates the fate of solutes in the environment. Many of these solutes are polar or even charged (1). Adsorption of these compounds to SPE materials is a promising way to help detecting them, as concentrations are often still too low for MS and preconcentration can overcome this problem. Many materials have been employed for this purpose (2, 3), but little is known about the exact sorption mechanism of these polar compounds (4). The role of functional groups of these solutes and the SPE materials is still ambiguous. How do they interact with each other and what is the part of water in the adsorption process? Apart from that, the effects of other compounds, such as inorganic salts, on the sorption behaviour is not yet well-understood. This knowledge can also be used for the removal of these compounds from drinking water. Often they pass through the treatment plant, as the current treatment methods cannot remove them effectively.

2. Aim of the research

Aim of the research is to get a better insight into the influence of various functional groups of selected chemicals (Figure 1) and SPE materials on the sorption. In case of charged organic compounds, additionally the impact of competing inorganic electrolytes was monitored. We decided to use OASIS polymers. These polymers carry polar moieties, hydrophilic parts as well as charged groups, which should allow the adsorption of the target compounds. Various chemicals were tested in varying salt solutions to determine which functional group in the compound is crucial for a successful sorption on the OASIS material. This knowledge is vital to taking a grounded decision which sorbent should be employed.

Figure 1: Some of the compounds tested in this research

3. Experimental approach

The experiments were conducted in different water matrices to determine the influence of functional groups and electrolytes on sorption affinity and capacity. The data received by fitting Langmuir (i) or Freundlich equations (ii) were used to discuss the sorption behaviour.

K L ⋅Cmax ⋅Cw (i) Cs = (ii) logCs = nlogCw + log K F 1+ K L ⋅Cw

4. Results

The results of this research indicate that especially apolar functionalities have a great impact on the sorption, whether the compound is charged or not. The more pronounced the apolar moiety is, the better the compound can adsorb (Figure 2 left). Furthermore, it emerged that the conditions of the aqueous phase, such as salt concentration, influence the sorption behaviour of charged molecules dramatically (Figure 2 right). The higher the salt concentration is, the lower the adsorption of the charged compounds. Apart from concentration also the type of ion is important.

1000

100 BSA

Cs (mmol / kg) Ibuprofen

10 0.0001 0.001 0.01 0.1 Cw (mmol / L)

Figure 2: Langmuir isotherm of benzenesulfonic acid (BSA) and ibuprofen to an anion exchanger (left), Freundlich isotherms of the sorption of metformin to a cation exchanger for different salt solutions (right)

5. References

1. Schriks, M.; Heringa, M. B.; van der Kooi, M. M. E.; Voogt, P.; van Wezel, A. P., Toxicological relevance of emerging contaminants for drinking water quality. Water Res. 2010, 44, 461-476. 2. Scheurer, M.; Sacher, F.; Brauch, H. J., Occurrence of antidiabetic drug metformin in sewage and surface waters in Germany. J. Environ. Monit. 2009, 11, 1608-1613. 3. Alvarez, D. A.; D., P. J.; Huckins, J. N.; Jones-Lepp, T. L., Development of a passive, in situ, integrative sampler for hydrophilic organic contaminants in aquatic environments. Environ. Toxicol. Chem. 2004, 23, 1640-1648. 4. Harman, C.; Allan, I. J.; Bäuerlein, P. S., The Challenge of Exposure Correction for Polar Passive Samplers - The PRC and the POCIS. Environ. Sci. Technol. 2011, 45, 9120-9121.

Stimulation and Inhibition of bacterial growth by caffeine dependent on antibiotics and silver nanoparticles – a ternary toxicity study using a microfluid segment technique

Jialan Cao1, Dana Kürsten1, Steffen Schneider1, Andrea Knauer1 Karin Martin2 and J. Michael Köhler1 1Ilmenau University of Technology, Institute of Micro- and Nano Technologies/ Institute for Chemistry and Biotechnology, Dept. Physical Chemistry and Micro Reaction Technology, Ilmenau, Germany 2Leibniz-Institute for Natural Product Research and Infection Biology Hans-Knöll-Institute (HKI), Department Bio Pilot Plant, Jena, Germany E-mail contact: [email protected]

1. Introduction The protection of organisms from damaging effects of toxic substances is one of the elementary goals for health care and sustainable management of the environment. The hazard assessment is based on the quantification of effects caused by the single substance rather than chemical mixtures. However, each organism is exposed to a complex and permanently changing mixture of substances outside and inside its cells, tissues and organs. At this point, the investigation of dose-response relations is extended from a one- dimensional problem into a higher dimensional problem. This challenge cannot be addressed by conventional toxicological approaches. New techniques are required, which allow for the realization of dose- related investigations in a large series of biological tests with low consumption of chemicals and biological materials and within a reasonable time need.

Such a possibility is given by the application of microfluidics and micro reaction technology in toxicological screenings. Beside micro- and nanotiterplate techniques, the use of closed fluid channels is particularly suited for the realization of biological studies inside small single volumes. This technique is based on the spontaneous and regular formation of fluid segments during the injection process connected with the possibility of an easy tuning of segment compositions. This effect is of particular importance for experiments with varied concentrations of components. It was already demonstrated for toxicological experiments with one or two components [1, 2]. Here, the application of this technique was investigated for the fast generation of three dimensional concentration spaces for screening of toxic effects of selected antibiotic substance and silver nanoparticles on the toxicity and activation of bacterial growth by caffeine.

2. Experimental The experimental set-up for the generation of microfluidic segments is shown in figure 1. Segments were formed by coinjection of all components into a flow of the carrier solution PP9 (perfluoromethyldecalin) by using a Peek 7-port manifold. Therefore, the manifold was connected via Teflon tubes (0.5 mm ID, 1.6 mm OD) with a computer-controlled, nearly pulsation free, syringe pump with six dosing units.

Figure 1: Experimental set-up for the generation and the analysis of microdroplets for three-dimensional screenings. After their formation, the segments are transported with constant flow rate through a flow-through photometer and fluorimeter, which measure directly through the transparent FEP tubing. The tube coils consisted of a PMMA plate with rolled Teflon tubes with a length of six meters used to store and to incubate the generated segment sequences for every measurement. The response of cultures inside segments was evaluated by two independent optical measurements, which supply two sets of complementary information about the evolution and activity of bacteria. The total of final cell numbers is well reflected by the reduction of the intensity of transmitted light by use of a microflow-through photometer. A certain measure for the viability is given by the endogenous cellular autofluorescence activity by use of a micro flow-through fluorimeter. Results and discussion We investigated the ternary mixture of the effectors chloramphenicol, silver nano particle and caffeine on bacterium E. coli. For the 3D-Screening, the concentrations of all three effectors were varied in 6 steps (0, 20, 40, 60, 80 and 100 % of the maximal concentrations). The maximum concentration of chloramphenicol, caffeine and Ag-NP were set to 4.8 µgmL-1, 20 mM and 0.7µgmL-1, respectively. In accordance to the flow program we found strong inhibited growth as well as autofluorescence signal for a mixture with a maximum concentration of all three effectors whereas combination between the min. and max. mixture concentration showed a non-monotonous behavior. A detailed image of the cellular response on the variation of the concentrations by different mixtures in a complete three-dimensional concentration space is given with the synopsis of six bolographic maps as shown in Fig. 2. These maps show the expected suppression of bacterial growth at high concentrations of Ag-NP and chloramphenicol, but include detailed information on the shift of lethal concentrations and on concentration-dependent stimulation effect. The non-monotoneity of the response of bacteria on caffeine at elevated chloramphenicol concentrations stands for principle changes in chemical interactions or physiological mechanisms inside the cells. Figure 2: Dose-response relations on autofluorescence intensity after 21 h E. coli cultivated inside 500 nL segments in 3-D concentration spaces of caffeine, chloramphenicol and Ag-NP represented by six isobolographic maps. a) without Ag-NP, b) 20 %, c) 40 %, d) 60 % e) 80 % and f) 100 % AgNP.

4. Conclusions

The concept of multi-dimensional screenings through microfluid segment sequences presents an alternative method to conventional toxicological methods with the advantage of getting a high amount of information in one experimental run. In future it will be combined with time-resolved measurements and miniaturized methods for multi-endpoint detection to extend response parameters.

5. References [1] A. Funfak, J.L. Cao, A. Knauer, K. Martin, J.M. Kohler, J Environ Monitor, 13 (2011) 410-415. [2] D. Kuersten, J. Cao, A. Funfak, P. Mueller, J.M. Köhler, Eng Life Sci, 11 (2011) 1-8. Acknowledgement - This research was financially supported by the German Federal Environmental Foundation (DBU 20009/009) and by the BMBF/VDI/VDE-IT (OPTIMI project, KFZ-16SV3701). Passive dosing under the microscope reveals that microorganisms enhance the mass transfer of hydrophobic organic chemicals

Dorothea Gilbert1,2, Hans-Henrik Jakobsen3, Anne Winding1, Thomas Backhaus2 and Philipp Mayer1

1Dept. of Environmental Sciences, Aarhus University, Frederiksborgvej 399, DK-4000 Roskilde, Denmark 2Dept. of Plant and Environmental Sciences, Gothenburg University, Box 461, SE-405 30 Göteborg, Sweden 3Dept. of Biosciences, Aarhus University, Frederiksborgvej 399, DK-4000 Roskilde, Denmark

E-mail contact: [email protected]

1. Introduction Stagnant boundary layers (SBLs) are often found at the interface of environmental compartments and are known to limit diffusive mass transfer processes of hydrophobic chemicals. Microgradients are then formed for instance in soil pore spaces or in thin aqueous films covering solid surfaces. Such gradients are important, because they determine the exposure situation in microhabitats as well as the direction and extent of mass transfer. The diffusive mass transfer of hydrophobic organic chemicals (HOCs) through SBLs may be significantly altered by certain medium constituents as has been previously shown by Mayer et al. [1]. Here, we hypothesize that motile microorganisms living in aqueous boundary layers might actively contribute to an enhanced mass transfer of HOCs through SBLs.

The aim was therefore to develop an experimental system that allows (1) direct microscopic observations of exposed organisms in controlled gradients of HOCs on microscope slides and (2) exploring and quantifying the possible effect of motile microorganisms on the mass transfer of HOCs.

2. Materials and methods Passive dosing using silicone was employed on microscope slides to produce gradients of HOCs. Silicone O-rings were placed in a Dunn Chemotaxis Chamber [3], whereby an inner loaded ring served as a source and an outer clean ring as a sink for HOCs to form a gradient over the bridge between the rings (fig. 1).

Figure 1: Cross-section of a modified Dunn Chemotaxis Chamber with silicone O-rings. Six PAHs covering a range of physico-chemical properties and toxic potential were used as model compounds. Source rings were loaded by partitioning from a methanol-water solution containing the PAHs [1, 2]. Fluorescence microscopy was then used to visualise the gradient with the model PAH fluoranthene. In a first experiment, the diffusive mass transfer of PAHs through air and water was quantified to determine the gradient’s stability. A second experiment was conducted to test whether motile organisms in the gradient would enhance the mass transfer of PAHs. Therefore, the freely swimming ciliate Tetrahymena pyriformis was exposed to gradients of PAHs for 24h. In parallel, chambers with protozoan medium only were assembled as a reference. The mass transferred from source to sink in the presence of protozoa was then quantified and expressed as a velocity rate constant kprotozoa. This value was normalized to the velocity rate constant for the diffusive mass transfer of PAHs through medium kmed, yielding the enhancement factor EF = kprotozoa/kmed. During exposure, the swimming of protozoa was recorded by video imaging microscopy using an infra-red light illumination, and subsequently analysed for behavioural changes. Videos were also recorded under fluorescent illumination to visualize the uptake, release and the cell-mediated transport of fluoranthene.

3. Results and discussion

3.1. Gradient characterisation Fluorescence microscopy confirmed that a nearly linear gradient of fluoranthene was established over the bridge in the Dunn chamber. Quantification of the diffusive mass transfer of PAHs through air and water showed that gradients remained highly stable for several days, except for naphthalene in air. The mass transfer through air was by one (benzo[a]pyrene) to two (naphthalene) orders of magnitude higher than through water. Experimental results were in good agreement with diffusive model predictions.

3.2. Microorganism-facilitated mass transfer The presence of T. pyriformis in the gradient significantly enhanced the mass transfer of PAHs. Enhancement factors increased with increasing hydrophobicity of the compounds (fig. 2) and ranged from min. 1.6 (naphthalene) to max. 95.8 (benzo[a]pyrene).

100 ) med /k 10 protozoa (k

mass transfermass enhancement 1 2 4 6 8

log Kow

Figure 2: Enhancement factors for the PAH mass transfer by Figure 3: T. pyriformis before uptake fluoranthene (pale cells) T. pyriformis plotted against Kow. Symbols represent the and after uptake of fluoranthene (blue cells) as well as a part mean rate constants (3 replicates from 3 independent of the source ring (blue). Dark-field illumination in experiments) together with the standard error of the mean. combination with UV-excitation was used.

Fluorescence microscopy showed that protozoa that had taken up fluoranthene appeared strongly blue. Their trajectories could be followed from the fluorescent signal. On the contrary, protozoa in the sink well were not visible under these conditions and could only be observed when in addition a dark-field illumination was used (fig. 3). This revealed that the organisms acted as a transport vector for PAHs via their diffusive uptake and release.

4. Conclusions

A new experimental platform was developed that allows for direct microscopic observations of small organisms during exposure to HOCs. It revealed that motile microorganisms can significantly enhance the mass transfer of hydrophobic chemicals across stagnant boundary layers -- a phenomenon, that, to our knowledge, has not yet been described.

5. References [1] Mayer P, Fernqvist MM, Christensen PS, Karlson U, Trapp S. 2007. Enhanced diffusion of polycyclic aromatic hydrocarbons in artificial and natural aqueous solutions. Environ. Sci. Technol. 41:6148-6158. [2] Smith KEC, Oostingh GJ, Mayer P. 2010. Passive dosing for producing defined and constant exposure of hydrophobic organic compounds during in vitro toxicity tests. Chem. Res. Toxicol. 23:55-65. [3] Zicha D, Dunn GA, Brown AF. 1991. A new direct-viewing chemotaxis chamber. J Cell Sci 99:769-775.

Acknowledgement - The authors thank Hawksley and Sons Ltd. for providing modified Dunn Chemotaxis Chambers. Financial support was given through the OSIRIS project and the Research School of Environmental Chemistry, Microbiology and Toxicology (RECETO). Comparison of two monitoring strategies for organic pollutants in seawater: passive sampler devices vs transplanted clams

Moreno-González, R.1, González, E., Campillo, J.A., Llorca-Porcel, J.2, Tortajada, R.2, León, V.M.1

1 Instituto Español de Oceanografía, Centro Oceanográfico de Murcia, Apdo. 22, C/ Varadero 1, 30740 San Pedro del Pinatar, Murcia (Spain). 2 LABAQUA-INTERLAB. Polígono Industrial Las Atalayas, C/Dracma, 16-18 03114 Alicante, Spain E-mail contact: [email protected]

1. Introduction The concentration of organic pollutants in seawater shows a great spatial and temporal variability as a result of a combination of natural and anthropogenic effects. Consequently an reliable method is required to monitor pollutants at trace levels in this environmental matrix, such as the use of bioindicator species or passive sampling devices. Water monitoring provides a snapshot of the concentration of pollutants in the environment, while the use of biota and passive samplers monitoring conducts to a time-integrated water column concentration. In this study we have characterized simultaneously the bioaccumulation in transplanted clams and two passive sampling devices (semipermeable membrane device, SPMD, and continuous flow integrative sampler, CFIS). The combination of these monitoring techniques with the analysis of water concentrations allows a comprehensive knowledge of the environmental status and to assess the representativity of these integrative sampling methods. The efficiency of these two passive samplers and the determination of the bioaccumulation of organic pollutants in transplanted clams were tested in the marine environment in spring and autumn. The study was performed in four selected sampling points in Mar Menor Lagoon (SE of Spain), which is subjected to direct and indirect discharges of organic pollutants. El Albujón Wadi is the main surface watercourse that flows into this lagoon from Cartagena Field, which is one of the most relevant horticulture areas in Europe. The specific objectives of this study were: a) to determine the seasonal and daily concentration of organic pollutants in marine waters and in El Albujón watercourse mouth, b) to determine the mean concentration of organic pollutants for a week using SPMD and CFIS in spring and autumn c) to compare repeatability and the efficiency of both passive samplers for the integration of marine samples in the considered periods d) to determine the concentration of organic pollutants in clams and the corresponding bioconcentration factor and e) to assess the correlation among the concentrations of the two sampling devices and clam, and seasonality of the concentration for organisms.

2. Materials and methods Clams were obtained from an environmentally protected area and subjected to a four days depuration period (T0) previous to be transplanted in the selected sampling points. Commercial stir bars (20 mm×0.5 thick and 49 µL of PDMS) used in CFIS were supplied by Gerstel (Mülheim a/d Ruhr, Germany). In this study four sampling points were considered to evaluate the mean concentrations Albuj Santiago de la Ribera of organic pollutants in the passive samplers and clams: close to Lo ón Lo Pagán Watercourse  Pagán Port (J1), at the south of Los Alcázares port (J2) and at J1 increasing distance from the mouth of the Albujón Watercourse (J3 at LOS ALCÁZARES   0.7 km and J4 at 2 km). The input of organic pollutants to the Mar AW J2 Sea Menor Lagoon through the El Albujón watercourse (AW) were  J3 simultaneously determined (concentration and flow). SPMD and CFIS  J4 Mar Menor were fixed to a stainless steel cage on the seabed (2-3 m depth), and Lagoon their repeatability were evaluated installing 2-3 sampling devices in Los Urrutias different sampling points. Clams (≈ 400 individuals per cage) were Mediterranean placed in baskets in stainless steel cages. Half of clams were sampled La Manga simultaneously with the passive samplers after a week of exposition del Mar Menor (T1), and the rest ones were sampled after a month exposition period Los Nietos Airport

(T2),.The analysis of commercial stir bars of CFIS was performed by Port

 Sampling point thermodesorption GC/MS [1]. The extraction and analysis of organic Playa Honda Wastewater pollutants in SPMD membranes applying the previously validated Treatment Plant method [2]. The analysis of organic pollutants (PAHs, PCBs,and Cabo de Palos organochlorinated pesticides) in clams were performance according to [3] and [4]. Figure 1: Sampling points in Mar Menor Lagoon and Albujón Watercourse. The efficiency of passive samplers was evaluated comparing the obtained integrative concentration with the real water one. With this goal, surface water was sampled daily with a Niskin bottle in the early morning and the late afternoon. PAHs, polychlorinated biphenyls(PCBs), triazines, organophosphorus and organochlorinated pesticides were analysed by stir bar sorptive extraction and thermal desorption coupled to capillary gas chromatography-mass spectrometry in surface [1] and marine water samples[5].

3. Results and discussion

3.1. Input of organic pollutants from El Albujón watercourse Significant daily, weekly and seasonally differences were observed in the organic pollutants concentrations. In Spring 2010 the organic pollutants present in Albujon Watercourse mouth were mainly pesticides, plasticizers and surfactants, although other pollutants were also detected, such as PAHs.. In Autumn 2010 the main pollutants detected were PAHs, herbicides (propyzamide, terbuthylazine, terbutryn, pendimethalin…) and chlorpyrifos (0-12 ng/L in spring and 3-6000 ng/L in autumn). 4-Nonylphenol was detected in all sampling points, which concentrations ranged from 15 to 900 ng/L in spring but in autumn only was detected in J2 (205 ng/L)., 3.2. Efficiency of SPMD and CFIS in seawater Duplicate and triplicate of CFIS and SPMD were studied in several sampling points in order to study the repeatability (RSD<20%). The sampling points J3 and J4 were close to El Albujón Watercourse, and consequently showed a high variation in the organic pollutants concentrations, especially for nonylphenols, triazines and organophosphorus pesticides. The mean concentrations of 4-Nonylphenol detected with CFIS in spring were similar in the four sampling points (180-250 ng/L), lower concentrations were detected in autumn (4-27 ng/L).Chlorpyriphos was detected in spring in all cases, both in SPMD (4.8-130 ng/L), showing a great variability, and CFIS (4.68-17.25 ng/L): However this insecticide was only detected with CFIS (2-18 ng/L) in autumn. Consequently different sources and variability are present around Mar Menor lagoon 3.3. Seasonal bioconcentrations of organic pollutants in Ruditapes decussatus PAHs (14), PCBs (9) and organochlorinated pesticides (12) were determined in the two sampling periods. The total amount of PAHs at the beginning (T0) was higher in autumn 6.4 μg/kg w.w.) than in spring (3.8 μg/kg w.w.). In spring after a month exposition (T2) the concentrations were higher in cages J1, J2 and J4, whereas in Autumn only in J1 concentrations (7.25 μg/kg w.w) were higher than initial one. A decrease of concentrations both in spring and autumn was observed in J3. PCBs and organochlorinated pesticides concentrations were higher in T2 than in T0 for all cages, particularly in cages J3 and J4, which suggested that these cages reflected the input of these pollutants though El Albujón watercourse

4. Conclusions

A continuous flow of pollutants access to the Mar Menor Lagoon through the Albujón watercourse and a significant daily variation in their concentrations were observed. There is no ideal passive sampler for all the considered pollutants due to their ranges of log Kow as the different hydrodynamic conditions in each studied areas. In the case of clams the intermediate exposure time (T1) was too short to reach similar pollutants levels found in CFIS or SPMD. However it was observed an increase of the bioconcentration for the majority of detected pollutants at the final exposure time (T2). References [1] León VM, Llorca-Porcel J, Álvarez B, Cobollo MA, Muñoz S, Valor I. 2006. Anal.Chem.Acta 558:261-266. [2] Huckins, J, Petty J. Booij K. 2006. Monitors of Organic Chemicals in the Environment by Semipermeable Membrane Device. Ed. Springer. [3] Viñas, L., Franco,A., González, J.J. 2002. Polycyclic Aromatic Compounds, 22, 161-173. [4] Fernández, B., Campillo,J.A.,Martínez-Gómez,C, Benedicto,J. 2010. Aquatic Toxicol. 99: 186–197. [5] Pérez-Carrera E., León VM., Gómez-Parra A, González-Mazo E. 2007. J. Chromatogr. A, 1170: 82-90. Acknowledgement - This work has been supported by the Spanish Inter-Ministerial Science and Technology Commission through ‘DECOMAR’ project (CICYT, CTM2008-01832) and by Seneca Foundation (Region of Murcia, Spain) through ‘BIOMARO’ project (15398/PI/10). A passive sampling method for the estimation of concentrations in pore water and accessible concentrations of polycyclic aromatic hydrocarbons in contaminated sediments

Foppe Smedes1 and Kees Booij2

1 Recetox, Masaryk University, Faculty of sciences, Kamenice 126/3, 625 00, Brno, Czech Republic 2 NIOZ Royal Netherlands Institute for Sea Research, P.O. Box 59, 1790 AB Texel, The Netherlands

E-mail contact: [email protected]

1. Introduction

The free dissolved concentration (Cw) in the pore water is a highly relevant quantity for the environmental risk assessment of contaminated in sediments, because it is proportional to the chemical activity – the driving force for partition controlled uptake by organisms (1) and transport. The second important parameter is the accessible concentration in the sediment phase (Cas) (1), which is the capacity of the sediment to maintain high concentrations in the pore water when contaminants are removed by uptake by organisms, degradation, tidal flushing, drainage, or other processes. The accessible concentrations in sediment are often small compared with the total concentrations, due to sorption to soot and coal fragments, which have strong sorption characteristics (2). A measure of the accessible concentration can be obtained by extraction of sediment suspensions with TENAX for a given period of time (3). For estimation of Cw in sediment suspensions solid phase micro extraction (SPME) has been applied (4), as well as other passive sampling materials, such as polyoxymethylene (POM) (5), and low density polyethylene (LDPE) (6). An important consideration with these methods is that the sampler mass is small enough to prevent a lowering of Cw (i.e., non-depletive extraction). Using PDMS coated vials with different film thicknesses, a non-depletive condition could be confirmed for estimating the Cw of PAHs in sediments (7). However, the occurrence of depletion can also be an advantage if the aim of a study is to quantify the accessible contaminant concentration. Here we report results for equilibrations of sediment suspensions and silicone rubber passive samplers at a range of silicone-sediment phase ratios. We show that Cw can be estimated at low as well as high depletive situations. The result allow the estimation of the initial (non-depleted) concentration in the pore water and the accessible concentration in the sediment demonstrated for PAHs using three sediments from different areas in the Netherlands.

2. Experimental Sediment samples from 3 different areas in the Netherlands were equilibrated with PDMS samplers by shaking at 150 rpm for 28 days with 4-5 different sampler-sediment ratios ranging from 0.03 to 1 at a suspension density of 0.1 g mL-1. Samplers were analysed for PAHs using HPLC with fluorescence detection. The total PAHs concentrations were measured after soxhlet extraction of the freeze dried sediment. Additionally from one sediment sampler uptake curves were recorded for up to 6 days in suspension density’s of 0.01, 0.02, 0.5, 0.1 and 0.3 g mL-1 at a constant sampler-sediment mass ratio (3 g/20 g).

3. Results and discussion Experiments preceding this work had indicated that the applied exposure period of 28 days was sufficient to attain equilibrium. So from the amount Np analysed on the samplers for each equilibration the Cw was calculated by dividing Np by Kpw mp where mp is the mass of the sampler and Kpw the sampler-water partition coefficient (8). Further, with ms as the mass of the sediment, also the concentration (Cs) remaining TOT in the sediment after equilibration was calculated by subtracting Np/ms from the total concentration (Cs ) as determined by soxhlet extraction. For fluoranthene the results are depicted in Fig 1 where the vertical line TOT on the right hand side represents Cs and the inserted points represent the results of each individual 0 equilibration. Assuming linear sorption the initial concentration in the pore water (C w) and the initial 0 accessible concentration in the sediment (C as) were estimated by non-linear least squares regression based 0 0 on the mass balance and Np as input variable. The values for C w and C as were used to construct the dashed line in Fig 1 of which the slope equals the reciprocal value of the sediment-water partition coefficient (Kasw) for the accessible fraction. The close fit of the line with the data justifies the assumption of linearity. TOT Fig 1 shows clearly that a large part of Cs is less accessible or inaccessible in the time frame of the exposure. Cw is reduces by a factor five after only 25 %. Is released from the sediment. Throughout all compounds and samples this releasable fraction ranged from 10-50%.

35 TOT Cs 1200 30 C 0 ) ) w ) ) ) 1 1 - - 25 ng ng ng L L 800 ng ng 20 ( ( w w 15 C C Uptake ( Uptake Uptake ( Uptake Uptake ( Uptake 0.3 g mL-1 10 400 0.1 g mL-1 5 inaccessible 0 0.04 g mL-1 Cas 0.005 g mL-1 0 0 0 100 200 300 0 2 4 6 C ( µg kg-1) Exposure time (d) s

Fig 1 Cw versus Cs for fluoranthene, The line on Fig 2 Uptake curves for pyrene for different the right indicates the total concentration. See suspension densities text for further explanation.

The results of uptake experiments conducted at different suspension densities showed that uptake rates increase largely with suspension density(Fig 2). Assuming that for the sediment the release rate is not affected by the suspension density these results show that apparently the uptake rate of the sampler is higher in dense suspensions. Using a model for the sediment-sampler-water exchange, uptake rate constants were estimated and related to the various experimental conditions. The model also showed why for high sampler-sediment phase ratios equilibrium is approached faster. The results are highly relevant for the risk assessment of contaminated sediments.

4. References 1. Reichenberg, F. and Mayer, P. Two complementary sides of bioavailability: Accessibility and chemical activity of organic contaminants in sediments and soils. Environ Toxicol and Chem 2006, 25, 1239-1245. 2. Cornelissen, G.; Gustafsson, O.; Bucheli, T.D.; Jonker, M.T.O.; Koelmans, A.A.; Van Noort, P.C.M. Extensive sorption of organic compounds to black carbon, coal, and kerogen in sediments and soils: Mechanisms and consequences for distribution, bioaccumulation, and biodegradation. Environ. Sci. Technol 2005, 39, 6881-6895. 3. Cornelissen, G.; Rigterink, H.; ten Hulscher, D.E.M.; Vrind, B.A.; Van Noort, P.C.M. A simple Tenaxr extraction method to determine the availability of sediment-sorbed organic compounds. Environ Toxicol and Chem 2001, 20, 706-711. 4. Mayer, P.; Vaes, W.H.J.; Wijnker, F.; Legierse, K.; Kraaij, R.H.; Tolls, J.; Hermens, J.L.M. Sensing dissolved sediment porewater concentrations of persistent and bioaccumulative pollutants using disposable solid-phase microextraction fibers. Environ. Sci. Technol 2000, 34, 5177-5183. 5. Jonker, M.T.O. and Koelmans, A.A. Polyoxymethylene Solid Phase Extraction as a Partitioning Method for Hydrophobic Organic. Environ. Sci. Technol 2001, 35, 3742. 6. Booij, K.; Hoedemaker, J.R.; Bakker, J.F. Dissolved PCBs, PAHs, and HCB in pore waters and overlying waters of contaminated harbor sediments. Environ. Sci. Technol 2003, 37, 4213-4220. 7. Reichenberg, F.; Smedes, F.; Jonsson, J.; Mayer, P. Determining the chemical activity of hydrophobic organic compounds in soil using polymer coated vials. Chemistry Central Journal 2008, 2, 8. 8. Smedes, F.; Geertsma, R.W.; Zande, T.v.d.; Booij, K. Polymer-Water Partition Coefficients of Hydrophobic Compounds for Passive Sampling: Application of Cosolvent Models for Validation. Environ. Sci. Technol. 2009, 43, 7047-7054.

Acknowledgements: The work was performed at the National Institute for Coastal and Marine Management (RIKZ), Haren, The Netherlands. Evaluation of an in-situ equilibrium sampling device for persistent organic pollutants in sediment pore water systems on the basis of solid phase microextraction (SPME)

Katharina Schmidt1, Susann-Cathrin Lang1, Detlef Schulz-Bull2, Dagny Ullmann1, Gotja Schaffrath1, Gesine Witt1

1University of Applied Sciences Hamburg,Lohbrügger Kirchstraße 65, 21033 Hamburg, Germany 2Baltic Sea Research Institute, Seestraße 15, 18119 Rostock E-mail contact: [email protected]

1. Introduction When assessing the ecotoxicological risk of contaminated sites, bioavailability of contaminants must be taken into account. To this end, the contaminant’s total amount is no suitable measure since it addresses neither of the two aspects of bioavailability as defined by Reichenberg and Mayer [1]: (1) Accessibility: The quantity of the contaminant in the system which can be made available for an organism, i.e. the fraction which is not “trapped” by the environmental matrix. (2) Chemical activity / Fugacity: The contaminant’s potential for spontaneous physicochemical processes such as partitioning between different phases/compartments in an environmental system, including partitioning into biological membranes/tissues (bioaccumulation). Chemical activities are often expressed in the more descriptive freely dissolved aqueous concentration. Our objective was therefore the development and field-testing of a sampling device based on equilibrium passive sampling in order to assess the in-situ chemical activity of POPs in natural sediments. Other than in previous studies [2, 3] the SPME fibers are brought into direct contact with the sediment as this shortens equilibrium times considerably. For method development, we focused on two classes of common sediment contaminants: polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs).

2. Materials and methods

2.1. Sampler design The sampling device is composed of two separable units: the fiber assembly and, around that, a protective housing. The housing was attached to a stainless steel rope with 2 stainless steel lashing cleats for retrieval of the sampler. We chose copper as base material in order to inhibit biofouling of both the device itself and the silicone coated fibers. The fiber assembly can hold up to nine SPME fibers of various diameters as well as a hollow fiber, i.e. flexible silicone tubing. These fibers are mounted on a frame (fiber length, 95 mm) where they are fixed by a PTFE-armored clamp. The rigid cylindrical housing is made from a perforated copper pipe (inner diameter, 40 mm; wall thickness, 2 mm; diameter of holes, 5 mm) through which fine-grained sediment particles can pass and come into contact with the SPME fibers while larger objects, e.g. mussel shells are kept outside. For method validation, equilibrium concentrations in Fiberguide SPME fibers exposed to the sediment by the new sampling device were compared with concentrations from in-vitro matrix-SPME as described by Witt [4].

2.2. Tank and field experiments In a first approach, a glass tank was filled with 2 L of wet sediment of Hamburg harbor which was carefully overlaid with additional water from the sampling site. The sampling device was placed on the sediment surface. Due to its self-weight, the device sank into the sediment until it was completely covered. Fibers were exposed at room temperature for 14 d in the dark. Two freshwater sampling sites were chosen to evaluate the operational reliability and the sampling efficiency of the device under field conditions: (A) A rather pristine town canal in the suburbs of Hamburg/Germany, sampled in winter; a corresponding matrix-SPME experiment was carried out at the assumed water temperature of 4 °C; (B) The Elbe River near Geesthacht/Germany, sampled in early-summer. In both cases, the sampler was deployed and fixed to a mooring platform. Samples were recovered after 20 days. Sampler position was manually checked both at deployment and recovery. 3. Results and discussion

3.1. Sampler design Full functionality of the sampler design was demonstrated in the tank and field experiments: The device was sunk by its self-weight and immersed in the sediment without any additional ballast or anchorage having been applied. Upon recovery, sediment coverage and position of the sampling device were unchanged. The perforated copper pipe had filled up with sediment but all fibers were undamaged and apparently free from biofouling. As intended, the sampler housing protected the SPME fibers from breakage and other mechanical damage while sediment particles penetrated through the perforations. Full contact between sediment and fiber surface was achieved. Microbial deterioration of the fiber surfaces was prevented due to the biocidal properties of the copper. The device’s fiber holding fixture is capable of accommodating several passive samplers of different formats in parallel, i.e. SPME fibers and PDMS tubing. This allows for replication and internal validation of the measurements as proposed by Reichenberg [5]. Because SPME fibers are not subject to intense sample clean-up, detection and quantification limits clearly depend on levels of non-target substances which might disturb chromatographic analysis. In our analyses, we estimated the limit of quantification to be cfree≈ 50-200 pg/L. Hence, the in-situ method covers a wide range of contamination levels in natural sediment pore water systems.

3.2. Performance-testing Compared to in-vitro SPME, fibers exposed to sediment with the sampling device did not yield significantly different results. Absence of sample agitation during extraction was successfully compensated by prolonged equilibration times. On the contrary, large deviations of single replicates, as observed in one of the test tubes of the tank experiment, are avoided by in-situ sampling. While subsampling of very small volumes for in-vitro SPME is sensitive to inhomogeneities in the sediment, the in-situ device covers a greater sample volume (per fiber) thus leveling out micro-scale inhomogeneities. The fact that laboratory and field extractions produced similar measurements does not render the in-situ approach superfluous. These similarities were aimed for and in-vitro conditions were adjusted to in-situ conditions in order to rule out any procedural shortcomings of the new sampling method. In bioavailability assessment such adjustments of in-vitro conditions are impracticable, especially when samples from different locations are to be assessed. Besides, true field conditions (e.g. temperature, salinity, pH) would never be reached.

4. Conclusions In this study, an equilibrium passive sampling device is introduced that makes POP bioavailability in terms of freely dissolved aqueous concentrations assessable on site, i.e. in the sediments. Hence, results are free from artifacts that may originate from sample treatment in in-vitro methods. The device is already applicable in a multitude of aquatic environments, especially where currents are low and sediments are muddy and well-mixed e.g. by bioturbation. Examples for such environments are mud flats, harbor basins, river banks and lakes. Greatest emphasis was put on functionality and robustness of the sampling device. Virtually indestructible, the device serves not only the purposes of fiber conveyance but those of sample protection from abrasion and biodegradation during field exposure. The versatility of the fiber assembly even offers potential for method validation. Internal equilibrium confirmation is possible by employing different sampling materials. Passive sampling by means of the in-situ sampling device has several advantages compared to in-vitro or solvent-based sample extractions that make it an ideal monitoring tool: (1) Most important, the ecologically relevant parameter ‘in-situ bioavailability’ is addressed instead of total sediment or pore water concentrations. (2) Due to short/medium equilibrium times, the temporal resolution of the measurements is suitable for analysis of both long-term trends and seasonal effects. (3) The device is of very solid construction and can be reused practically ad infinitum; only replacement of the disposable sampling materials contributes to its operational costs. (4) Sample treatment is reduced to a minimum which in turn reduces possible sources of sample manipulations, measurement errors and analysis costs.

5. References [1] Reichenberg, F., Mayer, P. (2006). Environ. Toxicol. Chem., 25, 1239–1245. [2] Maruya, K.A., Zeng, E.Y., Tsukada, D., Bay, S.M. (2009). Environ. Toxicol. Chem. 28, 733-740. [3] Van der Heijden, S.A., Jonker, M. (2009). Environ. Sci. Technol. 2009, 43, 3757–3763. [4] Witt, G., Liehr, G.A., Borck, D., Mayer, P. (2009). Chemosphere. 74, 522–529. [5] Reichenberg, F., Smedes, F., Jönsson, J.Å., Mayer, P. (2008). Chemistry Central Journal 2, 8 Chemistry Central Journal 2008, 2:8 doi:10.1186/1752-153X-2-8 Use of plants as passive samplers for volatile organic compounds (VOCs) in indoor environments

WJ Doucette1, T Wetzel1, JK Chard1

1Utah State University, Logan, UT E-mail contact: [email protected]

1. Introduction Volatile organic compounds (VOCs) including many with documented short- and long-term adverse health effects, are can enter indoor environments through internal (i.e. paints, paint strippers, fuels, cleaning supplies, pesticides, building materials, adhesives) and external sources (i.e. vapor intrusion from contaminated groundwater). Indoor air concentrations of VOCs vary widely, but concentrations of most VOCs are consistently higher indoors than outdoors. Typical approaches used to sample indoor air include evacuated canisters and sorbent tubes, however both are often considered intrusive by residents of the buildings being sampled. The use of ornamental plants has been suggested as a simple, unobtrusive, aesthetically pleasing, and cost effective method for sampling indoor air. The waxy surface of the leaves has the potential to provide a good surface for the passive capture of VOCs. However, the efficiency and kinetics of capture has not been well characterized.

2. Materials and methods To investigate the use of plants as indoor air VOC samplers, three types of studies were performed. The first consisted of monitoring air and plant concentrations over time after a controlled release of several VOCs into a residential building containing several plant species. The second study used a flow-through glass and stainless plant growth chamber to evaluate the relationship between air and plant leaf VOC concentrations. The third study used a headspace approach to measure equilibrium leaf-air partition coefficients.

Figure 1: Indoor air sampling.

Figure 2: Headspace and Flow through Leaf air partition coefficient measurements.

3. Results and discussion

3.1. Results of residential building indoor air and plant leaf sampling A consumer adhesive containing perchloroethene (PCE) was placed in an 2nd story room of a 2 level house. The air concentration of PCE was measured over time in several rooms using a sorbent tube/thermal desorption/ GC/MS method. Samples of plant leaf tissue (pothos and cactus) located in the same rooms were also collected and analyzed by headspace GC/MS. The relationship between the air and leaf concentrations is summarized in Table 1. Table 1: Results of indoor air and leaf sampling during residential release. Time (hrs) PCE air (ppbv) PCE leaf P (ug/kg) PCE leaf C (ug/kg) 0 0 ND ND 24 10 2.50 0.065 48 4.0 0.655 0.81 72 1.0 0.028 0.30 3.2. Results of headspace flow through chamber and leaf-air partition coefficients The results of leaf-air partition coefficients for obtained for PCE and TCE using a equilbrium headspace method and for TCE using a flow-through chamber method are shown in Tables 1 and 2 respectively. Table 2: Results of indoor air and leaf sampling during residential release.

TCE K PCE Spike Leaf-air Leaf-air (ng/vial) Leaf mass (g) (L/kg) (L/kg) 10.00 0.18 7.88 8.30 10.00 0.31 8.38 11.73 50.00 0.18 7.48 5.25 50.00 0.31 5.51 8.15 100.00 0.16 9.07 7.25 100.00 0.33 9.21 11.49 Average 7.92 8.70 std dev 1.24 2.29 Table 3: Results of indoor air and leaf sampling during residential release. K Leaf TCE Air TCE Leaf-air Plant type (ug/kg) (ug/L) (L/kg) Ave Std dev Pothos 0.13 0.02 6.72 Pothos 0.20 0.02 9.84 7.72 1.84 Pothos 0.13 0.02 6.61 Cactus 0.07 0.02 3.62 Cactus 0.13 0.02 6.69 4.73 1.71 Cactus 0.08 0.02 3.87

4. Conclusions

A strong relationship between room air and plant leaf concentrations was observed in the house release experiment. The resulting leaf to air concentrations ratios were similar to those obtained in subsequent preliminary flow-through chamber and equilibrium headspace studies suggesting that the collection and analysis of plant leaves may provide a less obtrusive method of monitoring indoor air quality. Additonal equilibrium and kinetic experiments for other VOCs and plant species are continuing. Acknowledgement - The authors thank the Utah Water Research Laboratory and Hill AFB for technical support and/or funding. Calibration and field evaluation of Polar Organic Chemical Integrative Samplers (POCIS) for monitoring pharmaceuticals in hospital sewage water

Emilie Bailly, Yves Levi, Sara Karolak

Univ. Paris-Sud 11, CNRS, AgroparisTech, UMR 8079, Groupe Santé Publique - Environnement 5 rue Jean-Baptiste Clément 92290 Chatenay-Malabry, France

Contact: [email protected]

1. Introduction Pharmaceuticals are an important group of emerging contaminants that have raised great concern due to their continuous release in the environment. After administration, pharmaceuticals are excreted in faeces and urine as unmetabolized (parent drug) or parent-drug conjugates and enter into the sewage system. Although wastewaters are treated at the sewage plant, some compounds are not efficiently removed and are released in receiving water leading to the contamination of surface and groundwater. The assessment of environmental and Public Health risks requires identifying qualitatively and quantitatively the main sources of pharmaceutical pollution. In this context, hospitals are supposed to be a great source of entry of pharmaceutical residues. In a previous study (MEDIFLUX) [1] carried out in our laboratory, we estimated the contribution of hospital to the urban sewage pollution by pharmaceuticals. This study was performed by collecting water samples at the exit of hospital with an automatic sampler. This type of sampler is not well adapted to hospital sewage pipes, heavy to use, and doesn’t allow obtaining several days or weeks mean sample. To go on, we decided to test Polar Organic Chemical Integrative Samplers (POCIS) for this type of monitoring. Passive samplers allow the measurement of Time Weighted Average (TWA) concentrations, overcoming many shortcomings of the spot sampling techniques, known to be expensive, time consuming and reflecting only the contamination level at the time of sampling. POCIS are particularly interesting for sampling semi- polar pharmaceuticals in water. However, they are mainly used to sample WWTP effluent or surface sample [2], [3]. Indeed, their use to sample sewage water is not well documented for the moment. We defined and optimized the use of POCIS in the case of hospital effluents taking into account of flow velocity, temperature and biofouling. The application of POCIS was studied using six compounds already selected as representative of the great families of pharmaceuticals used at the hospital (Atenolol, Prednisolone, Methylprednisolone, Sulfamethoxazole, Ofloxacin, Ketoprofen) [1].

2. Materials and methods Pharmaceutical-POCIS were home-made and consisted of 200 mg of Oasis HLB (hydrophilic-lipophilic balance) resin enclosed between two polyethersulfone membranes, held by two stainless steel washers. During exposure, contaminants are going to spread and fix on the receiving phase, two phases of accumulation are observed : a first one linear followed by a curvilinear regimen before reaching equilibrium. -1 In the linear phase, the concentration of the analyte in water (Cw, μg.L ) is linked with the concentration of -1 the analyte on the POCIS (CPOCIS, μg.g ) with the following equation : -1 Cw = (CPOCIS x MPOCIS) / (Rs x t) with MPOCIS: mass of the sorbent (g), Rs: sampling rate (L.day ) t: time of exposure (days). The sampling rate is specific for each compound and depends on environmental conditions, in particular flow rate, temperature, bio-fouling. After exposure, POCIS was dismantled and the sorbent was transferred into an empty solid phase extraction tube. The sorbent was eluted by methanol and the quantitative analysis was carried out by Ultra Performance Liquid Chromatography (UPLC) coupled to MS/MS. In a first step, POCIS were calibrated under laboratory conditions for the analytes of interest taking into account various relevant environmental conditions (temperature, flow rate..). POCIS were exposed under a constant agitation to water (tap water and waste water) spiked with the selected pharmaceuticals in a stainless steel tank. Dosing and maintaining a constant concentration of these compounds was achieved by renewing water every two days. Compound specific sampling rates, Rs, were then calculated before deployment in hospital sewage pipe. 3. Results and discussion

3.1. Calibration of POCIS First, sampling rates were determined through lab-based calibration under the following conditions: analyte concentrations in tap water ~ 10 µg/L, water flow 10 or 25 cm.s-1, temperature: 15, 20 or 25°C. In comparison to the different experiments, it appears that Rs increase significantly when flow rate increase between 10 to 25 cm.s-1 (student test, p<0,05) for all the compounds (except sulfamethoxazole for which the increase was not significant p = 0,32) Figure 1. A slight difference of Rs between 15 and 25°C was observed (student test, p<0,05) for sulfamethoxazole, prednisolone, ketoprofen.

. Figure 1: Comparison of Rs (L/d) between two conditions of flow rate. The accumulation phase was linear up to seven days for ofloxacine, prednisolone, methylprednisolone and ketoprofen whereas this phase was shorter for atenolol and sulfamethoxazole (2 to 5 days). The POCIS were then calibrated in hospital sewage. In a first step, the flow rate and temperature of waste water were recorded during a week on the selected hospital effluent. The mean temperature was 24°C and the mean flow rate was 16 cm.s-1 (with variations between 3 to 70 cm.s-1). For the calibration, 20 L of wastewater were taken from hospital effluents and brought to the laboratory to carry out Rs measurement in the stainless steel tank as for the previous measurement in tap water. Sewage water was changed every two days. The Rs values obtained were closed to Rs values in tap water.

3.2. Application in situ As the laboratory calibration step shows the feasability of POCIS to sample sewage water, we plan to deploy POCIS in situ. Some technical problems have been observed, mainly related to the presence of solids in sewage as toilet papers or wipes. Thus, we had to define specific deployment conditions to allow a reliable sampling.

4. Conclusions

The step of calibration was the main part of the work and its completion was needed before the application of POCIS in situ. The follow-up of accumulation made it possible to estimate the field of linearity in order to choose the optimal length of POCIS implantation in situ. The use of POCIS for the follow-up of contamination by organic pollutants is especially described for surface waters such as rivers, but very little studies report its use in wastewaters. This work gives encouraging results for the deployment of POCIS in sewage that could be a useful tool for pharmaceutical pollution management.

5. References [1] Mullot J-U. 2009. Modeling of Pharmaceutical loads in hospital wastewater. www.lspe.u-psud.fr/These Ju Mullot.pdf Accessed 20 November 2011 [2] Togola A, Budzinski H. 2007. Development of polar organic integrative samplers for analysis of pharmaceuticals in aquatic systems. Anal. Chem.J., 79:6734–41. [3] Bartelt-Hunt S.L., Snow D.D., Damon T., Shockley J., Hoagland K. 2009 The occurrence of illicit and therapeutic pharmaceuticals in wastewater effluent and surface waters in Nebraska. Environmental. Pollution, 157:786-791. Acknowledgement – We thank Region Ile de France for the grant Dim SENT, Anses for the material financing.

C01 –Advances in passive sampling and dosing techniques

Accumulation kinetics and sampling rates for 56 polar organic compounds, identification and validation of 5 PRCs

Nicolas Morin1,†, Cécile Miège1, Julien Camilleri2,†, Cécile Cren2, and Marina Coquery1

1Irstea (ex-Cemagref), UR MALY, Freshwater Systems Ecology and Pollution Research Unit, 3 bis quai Chauveau, CP 220, F-69336 Lyon, France 2Service Central d’Analyses (SCA), Echangeur de Solaize, Chemin du Canal 69360 Solaize † Both authors contributed equally to this work E-mail contact: [email protected]

1. Introduction Passive samplers are new emerging tools for sampling organic (polar or apolar) compounds or metals. They are immerged in aquatic media during days or months and they passively accumulate analytes. Therefore, they are able to conduct to time-weighted average (TWA) concentrations which can be more representative than concentrations from classical grab sampling. The POCIS (Polar Organic Chemical Integrative Sampler) was made for sampling polar organic contaminants in water [1]. There is still a need of research concerning its domain of validity (e.g. molecules sampled, type of water studied, optimal exposure duration) and its performances, including the definition of molecules sampling rates, repeatability, accuracy of the TWA concentrations. Performance reference compounds (PRCs) enable to decrease the effect of variable environmental conditions, so they can be used to obtain more reliable in situ TWA concentrations. To date, only one PRC has been identified for POCIS: deisopropylatrazine-d5, that has been used and proved efficient for polar herbicides monitoring in freshwaters [2, 3]. The aim of this work, done in laboratory, was firstly to evaluate the accumulation kinetics and sampling rates for 56 polar organic compounds (5 alkylphenols, 9 hormones, 11 pesticides, 27 pharmaceuticals, 3 phenols and 1 UV filter). Secondly, it was to determine PRCs among 30 deuterated molecules tested and to validate their use as internal surrogate to correct for environmental conditions during sampling. For these 2 purposes, 3 different experiments were performed with a flow-through calibration system.

2. Materials and methods Calibration system Three different experiments were performed with the same calibration system, schematised in figure 1. POCIS were immerged in 2 different aquaria For each experiment, parameters (temperature, pH, conductivity, flow velocities) were controlled and checked each week. Agitation in aquaria was ensured by a pump linked to a diffusion ramp with holes. Thus, the current arrived directly in the front of each POCIS (velocity of 10±5 cm/s).

Figure 1: Scheme of the calibration system. Kinetic accumulation experiment Unspiked POCIS were immerged for a maximum of 28 days containing spiked tap water at a nominal concentration of 3 µg/L. This concentration was checked twice a week. Triplicate analysis of POCIS were 22nd Society of Environmental Toxicology and Chemistry (SETAC) Europe Annual Meeting, 20 – 24 May, 2012, Berlin, Germany C01 –Advances in passive sampling and dosing techniques performed at 0, 1, 3, 6 and 12 hours and at 1, 3, 7, 14, 21 and 28 days. This experiment permitted to study the kinetic accumulation of each compound in the POCIS and to calculate their sampling rates using t1/2 criteria. Kinetic desorption experiment Spiked POCIS were immerged for a maximum of 28 days containing non spiked tap water. Triplicate analysis of POCIS were performed at 0, 3, 7, 14, 21 and 28 days. This experiment permitted to select 5 potential PRCs over the 30 deuterated compounds tested and to check if they undergo isotropic exchange comparing their exchange constant calculated in kinetic accumulation and desoprtion experiments. Validation PRCs experiment Triplicates of spiked POCIS were immerged for 14 days in spiked tap water. For each exposed triplicate, exposure condition was changed: it could be the temperature (10 or 20°C), the agitation (2 or 10 cm/s) or the nominal tap water concentration (3 or 15 µg/L). The aim of this experiment was to check if PRCs were able to correct previously determined laboratory sampling rates in order to obtain the TWA concentration of each compound knowing the accurate water concentration.

3. Results and discussion

3.1. Kinetic accumulation experiment Kinetic accumulation curves of the 56 molecules can be separated in 4 different groups. Molecules not or poorly accumulated (9 molecules), molecules with t1/2 lower than 14 days (12 molecules), molecules with t1/2 higher than 14 days (24 molecules) and molecules having an inflexion point in their accumulation curve (11 molecules). Sampling rates were all the molecules except those ones not or poorly accumulated. They varied from 0.004 L/d for metronidazole to 0.780 L/d for iprodione.

3.2. Kinetic desorption experiment Over the 30 deuterated compounds tested, 5 showed desorption from the receiving phase of the POCIS. Among these 5 compounds, 3 of them had more than 80% desorbed after 28 days of exposition. A comparison between their exchange constant calculated in the kinetic accumulation and desorption experiments for the 5 PRCs was performed showing that these compounds undergo isotropic exchange.

3.3. Validation PRCs experiment In this experiment, corrected sampling rates will be discussed as a function of the different controlled conditions. This experiment will permit to determine if PRCs can effectively correct laboratory sampling rates in order to be the more accurate from the known water concentration.

4. Conclusions

In this work, accumulation kinetics for 56 polar organic chemicals were measured using a robust experimental protocol. For some molecules, it was not possible to calculate a sampling rate because they had a poor affinity with the receiving phase. So, sampling rates were supplied for 47 molecules over 56 using t1/2 criteria. Moreover, 5 PRCs were identified over 30 compounds tested and they showed isotropic exchange. We will validate their use as internal surrogates exposing spiked POCIS in different controlled conditions in order to check if it is possible to better estimate TWA concentrations.

5. References [1] Alvarez, D. A.; Petty, J. D.; Huckins, J. N.; Jones-Lepp, T. L.; Getting, D. T.; Goddard, J. P.; Manahan, S. E. 2004. Development of a passive, in situ, integrative sampler for hydrophilic organic contaminants in aquatic environments. Environ Toxicol Chem 23:1640-1648 [2] Mazzella, N.; Dubernet, J.-F.; Delmas, F. 2007. Determination of kinetic and equilibrium regimes in the operation of polar organic chemical integrative samplers: Application to the passive sampling of the polar herbicides in aquatic environments. J Chromatogr A 1154:42-51 [3] Mazzella, N.; Lissalde, S.; Moreira, S.; Delmas, F.; Mazellier, P.; Huckins, J. N. 2010. Evaluation of the use of performance reference compounds in an Oasis-HLB adsorbent based passive sampler for improving water concentration estimates of polar herbicides in freshwater. Environ Sci Technol 44:1713- 1719

22nd Society of Environmental Toxicology and Chemistry (SETAC) Europe Annual Meeting, 20 – 24 May, 2012, Berlin, Germany Polar Organic Chemical Integrative Sampler (POCIS) calibration for steroid hormones and pharmaceuticals, and flow modelling in the calibration system

Perrine WUND1,2, Jérôme CHARTIER3, Gaëla LEROY2, Thomas THOUVENOT4, Valérie INGRAND2 and Hélène BUDZINSKI1

1 Univ. Bordeaux, EPOC-LPTC, UMR 5805, 351 cours de la Libération, 33405 Talence, France 2 Veolia Environnement Recherche et Innovation, Centre de Recherche de Saint Maurice, Immeuble «Le Dufy », 1 Place de Turenne, 94417 Saint Maurice Cedex, France 3 Veolia Environnement Recherche et Innovation, Zone Portuaire de Limay, 291 avenue Dreyfous Ducas, 78520 Limay, France 4 Veolia Environnement Recherche et Innovation, Centre de Recherche de Maisons-Laffitte, Chemin de la Digue, 78603 Maisons-Laffitte E-mail contact: [email protected]

1. Introduction Water pollution from emerging contaminants such as steroid hormones and pharmaceuticals is one of the important stakes of current environmental research. Several pharmaceuticals were selected to represent compound classes that are often encountered in the environment: Sulfamethoxazole and Erythromycin-H2O for antibiotics, Diclofenac for non-steroidal anti-inflammatory drugs, Bezafibrate for hypolipidemic agents and Carbamazepine for anti-epileptic drugs. Steroid hormones, either natural or synthetic, are also of major concern because they can interfere with the endocrine system even at low concentrations, so various steroid hormones (Estrone, α-Estradiol, β-Estradiol, Ethinylestradiol, Estriol, Mestranol, Progesterone, Testosterone, Norethindrone, Levonorgestrel) were included in this study as well. One of the main drawbacks of conventional grab sampling is the poor representativeness of the actual contamination. Passive sampling can be an alternative approach that provides a more accurate image of the contamination, while being easier to handle than large volume water samples. Polar Organic Chemical Integrative Samplers (POCIS) were calibrated for target compounds, and their desorption from samplers was investigated. Calibration of POCIS was conducted in a flow-through exposure system with stirring action provided by rotating blades. Computational Fluid Dynamics (CFD) modelling with Fluent software was carried out to assess the mixing efficiency of this sytem. Very few data have been published on this issue so far, which is crucial as various designs are currently being used to calibrate the POCIS.

2. Materials and methods

2.1. Experimental system design The samplers were exposed to pharmaceuticals and hormones in 27 liter tanks at nominal concentrations of 1 µg/L and 100 ng/L, respectively. The calibration was conducted at ambient temperature and dechlorinated tap water was stirred at 45 rpm. Two types of samplers were tested: POCIS in its classical « Pharm » configuration (200 mg Oasis HLB sorbent and Polyethersulfone membranes with 0.1 µm pores) and 200 mg Oasis HLB sorbent enclosed within two Nylon membranes with the same pore size. Samplers were regularly retrieved from the exposure system and replaced by fresh samplers (Figure 1).

Figure 1: Schedule of the calibration For desorption purposes, spiked HLB sorbent (5 µg/g) was prepared by sonicating the sorbent with target compounds and dichloromethane, which was then removed by rotary evaporation. Samplers were assembled with 200 mg of this spiked sorbent and either PES or Nylon membranes, and placed in the same tanks under the same exposure conditions (temperature, turbulence) as for the calibration. Samplers were regularly retrieved from the tanks to monitor the concentration decrease. 2.2. Extraction and analytical protocols Water samples were taken every day and stored frozen until extraction. Steroid hormones were extracted on Oasis HLB cartridges and pharmaceuticals on Oasis MCX cartridges. Both compound classes were analyzed by LC-MS-MS on a C18 column. After dismantling of the samplers, the sorbent was transferred into an SPE glass tube and dried under vacuum. All samplers extracts were analyzed and quantitated under the same conditions as water samples.

2.3. CFD modelling with Fluent software A steady-state calculation provided a characterization of the flow (velocity profiles, pathlines, and turbulence parameters). The second calculation was carried out in transient mode. A tracer injection was simulated and its concentration in water on the POCIS surfaces was monitored. k-ε standard turbulence model was used, which provided the best result accuracy to calculation time ratio. Three-dimensional conservation equations were solved. The system was considered as monophasic i.e. water and spiking solution were considered as clear water.

3. Results and discussion

3.1. Calibration experiment: uptake of target compounds A linear uptake was obtained for most compounds and sampling rates could be calculated by linear fit. Sampling rates obtained with Nylon membranes are consistently lower than sampling rates obtained with the classical configuration of POCIS. Accumulation of Mestranol occurred with a lag-time of several days when it was sampled with classical POCIS. This may be due to the hydrophobicity of Mestranol (log Kow = 4.67) which may slow down the crossing through the hydrophilic PES membrane. The use of more hydrophobic Nylon membrane limits this phenomenon and leads to a linear accumulation pattern. Sampling rates could not be calculated for Sulfamethoxazole because the equilibrium between sampler and water is reached very quickly, whatever the membrane used. This is because Sulfamethoxazole is quite hydrophilic (log Kow = 0.7) so it has a high affinity for the water phase.

3.2. Desorption of target compounds from samplers

No significant desorption of steroid hormones from HLB sorbent was noticed. Erythromycin-H2O, Bezafibrate, Diclofenac and Carbamazepine did not desorb from samplers either. Considerable desorption of Sulfamethoxazole occurred because only 5% of the initial amount spiked on HLB sorbent was left after 15 days. The membrane did not appear to play a major role in the desorption process.

3.3. CFD modelling Calculation with Fluent software showed that water flow at the surface of the samplers was relatively low compared to a river stream (0,035 m/s). An efficient mixing in the exposure tank was achieved after 30 min (less than 1% tracer concentration variability on the POCIS surfaces). Therefore, all samplers were exposed to the same concentrations during the calibration.

4. Conclusions

Two different POCIS designs were assessed in this study. The classical design proves to be valuable, particularly for more polar compounds. The substitution of PES membranes by Nylon membranes enables to sample integratively more hydrophobic compounds like Mestranol, but provides lower sampling rates i.e. compounds will less accumulate with this membrane type. CFD modelling confirmed the homogeneity in the exposure tank and provided an estimation of the flow at the surface of the samplers, which, to our knowledge, has not been done before. The design used to calibrate the POCIS offers a quite low water flow, which may not be representative of a river flow. Therefore, calibrations should be carried out with an increased turbulence or in a channel to improve the representativeness of the experimental conditions.

Acknowledgements – ANRT is acknowledged for the PhD grant, Région Aquitaine is acknowledged for financial support for technical equipement The use of passive samplers to constrain distributed models for pesticide surface runoff simulations.

Tom Gallé, Marion Frelat, Stefan Julich, Michael Bayerle and Denis Pittois

CRTE, CRP Henri Tudor, Luxembourg E-mail contact: [email protected]

1. Introduction Passive samplers yield data on average concentration during their exposure period.Yet their application is most useful to cover periods where concentrations are strongly fluctuating and the information hidden in the average value should be decrypted. Pesticides are emitted by two main episodically active pathways: emissions from Wastewater Treatment Plants (WWTP), which are the result of the spilling of leftovers and the cleaning of spraying equipment during application periods, and surface-runoff from agricultural fields during precipitation events. Passive samplers are easy to install in greater numbers and can therefore be used to track critical source areas for pesticides. The main issue relates to the quantitative nature of passive samplers. Sampling rates (Rs) can deviate rather largely under field conditions depending on the flow environment and the compound properties. Moreover, for the evaluation of peak concentrations the elimination rate (ke) for the substances during non-polluted periods follwing the peak is equally important. Hence a robust determination of k u (uptake rate) and ke is the basis for the interpretation of plumes that have been monitored by a passive sampler. This contribution shows uptake and elimination rates that have been determined in the laboratory and the field and how these parameters can be used to estimate peak concentrations during exposure periods of passive samplers. In combination with autosampler data from one site located near the basin outlet, contributions from low-flow and precitpitation events can be calculated with simple balancing of pesticide uptake by passive samplers during floodwaves for each site. The data have been used to refine sub-catchment emissions in a SWAT simulation.

2. Materials and methods Uptake rates for pesticides have been determined in the laboratory in quiescent and stirred conditions as well as in the field by monitoring daily profiles of pesticide concentrations with an autosampler (composite samples with 20 min resolution) and a simultaneously exposed passive sampler. POCIS HLB from EST were used in triplicate in 5 different sites on 15 individual days in total. Elimination rates were determined with pre-loaded passive-samplers that were exposed to clean water in the lab with 3 and 6 days exposure and switching of the water on the third day. In the field pre-loaded POCIS were exposed for 2,5,9 and 15 days. The investigated Wark catchment (Luxembourg) has an area of 82 km2 and is charcterized by loamy soils which favor surface runoff. The catchment also yields emissions of six treatment plants with approximately 7500 person equivalent loads. A water level triggered autosampler wa set up at the catchment outlet close to the river gauge.In parallel 6 passive samplers haven been exposed on tributaries and points of confluence in the river network. and 5 POCIS have been installed in WWTP outlets. The passive sampler exposure was continuous from March 15th to November 15th 2011 with a 14 day switching of devices. Pesticide analysis was performed on a Thermo Quantum Discovery Max LC-MS-MS with online concentration for the grab samples derived from the autosampler. LOQ of most substances were in the order of 5-10 ng/l. POCIS were eluted with an automated Gilson liquid handler GX-274 using 6.5 ml of aceto- nitrile/dichloromethane and 5 ml of methanol in sequence. Deuterated internal standards were added prior to the evaporation step and analyte concentrations corrected for internal standard recovery. Analysis of POCIS was performed without online concentration. Here, LOQ of most substances were corresponding to 1-2 ng of analyte sequestered in the sorbent of a POCIS. The SWAT model was calibrated using the river gauge at the catchment outlet with precipitation data from rain gauges in and nearby the watershed. Official data on crop types on the plot scale and pesticide use for cultures at the national level where provided by agricultural administrations. Substance properties (t1/2, KOC) were constrained using several event loads at the catchment outlet (autosampler site). 3. Results and discussion Profiles WWTP Niederfeulen Outlet 350 3.1. Field Rs values and ke 0.7 Discharge river Isoproturon 300 0.6 Bentazone Field determination of Rs values are depending on the /s] 3 Terbuthylazine 250 occurrence of the compounds during the daily exposure 0.5 period. The collection period is a compromise in terms 200 of LOQ for passive samplers and direct measurements. 0.4 150 The number of Rs collected is strongly dependent on 0.3 season and compound. Relative standard deviations for 100 0.2 Rs vary in general from 20% for the frequently detected Pesticide concentration [ng/l] to 50-60% for occasional or close to LOQ candidates. Average daily discharge [m 0.1 50 Losses from pre-loaded membranes in laboratory tests were negligible showing some correlation to the log 0.0 0

7 Jun 5 Jul 19 Jul KOW of the compounds. Field elimination experiments 15 Mar 29 Mar 12 Apr 26 Apr 10 May 24 May 21 Jun had not been concluded at the time this abstract was written but comparison of mean event concentrations Figure 1: Pesticide profiles at a WWTP outlet (14 days from autosamplers and POCIS already suggested ku to POCIS average concentration). River discharge is be much larger than ke. displayed for orientation.

3.2. WWTP emissions and immission data Warken River profiles Although far from being good pesticide handling practice, Discharge river 140 0.7 application periods for different pesticides can be read at Terbuthylazine 120 0.6 the outlet of WWTPs as illustrated for isoproturone, 100 bentazone and terbuthylazine in Niederfeulen (figure 1). 0.5 80 Following the application the first major flood events in 0.4 60 May-June generated pesticide runoff (figure 2). The loads 0.3

that can be mobilized through runoff are heavily /s] 40 3 0.2 depending on the half-lives of the compounds. For short- 20 lived pesticides like isoproturon or bentazone emission 0.1 from WWTPs during the application period account for 0.0 0 dominant fraction of the load while more recalcitrant 40 Discharge river compounds like terbuthylazine are dominantely emitted 0.7 Isoproturon through runoff. 92% of the terbuthylazine load collected 0.6 Bentazone 30 by the POCIS in June is runoff-related while in the same 0.5 Pesticide concentration [ng/l]

period 76 % of the isoproturone load is stemming from Average daily discharge [m 0.4 low-flow periods. 20 0.3 3.3. Distributed immission situation 0.2 10 0.1 Stand-alone passive samplers in the catchment cannot rely on balancing with the autosampler event loads. Here 0.0 0 the pharmaceutical carbamazepine has to be used as a 7 Jun 5 Jul 15 Mar 29 Mar 12 Apr 26 Apr 21 Jun 19 Jul regressor to estimate the low flow contribution (figure 3). 10 May 24 May In this way the hot spots of compound emissions can be identified and model calibration in SWAT can be fine-tuned with localized data (i.e. allocated to specific plots). This overcomes information gaps on the actual application of pesticides on specific surfaces, which is Bentazone spatial immission often a big uncertainty in pesticide runoff modelling. 35 1 30 Bentazone 24/05 4. Conclusions Bentazone 10/06 25 Passive samplers can be used to quantify contributions 20 from source areas within a catchment provided that k u 5 and ke have been determined and an autosampler station 15 is available for plausibility checking.

Bentazone [ng/l] 10 6 Acknowledgement - The authors thank the LIFE+ program 1 5 of the European Commission for funding the M3 project 2 5 4 6 (LIFE07 ENV/L/000540). 0 42 3 3 Figure0 3: 5 Carbamazepine10 15 20vs. Bentazone25 30 concentration35 from POCIS on 6 Carbamazepinesampling point [ng/l]s for two dates. Sampling points 1 and 5 show major runoff contributions (1-6 Figuredownstream 2 Pesticide order profiles of stations) in the river Wark (14 day POCIS average concentration). Snow, Contaminants and Climate Change Torsten Meyer1, Frank Wania1 1University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario, Canada M1C 1A4 E-mail contact: [email protected]

1. Introduction Effects of contaminants on organisms are most likely to occur when ambient concentrations and therefore exposures are high. While most processes in the environment lead to a dilution and degradation of contaminants, there are also mechanisms that concentrate and amplify contaminants in space and time. Understanding those mechanisms is not only an intriguing puzzle, but also important in efforts to minimise the potential for unexpectedly high exposure of organisms to contaminants [1]. Snow has a remarkable ability to contribute to contaminant amplification [2,3]. For example, on a large scale, a seasonal snow cover collects and stores atmospheric contaminants over the winter, only to release them in concentrated pulses during a short spring melt season. On a smaller scale, processes are operating within a melting snow pack that can further amplify contaminant concentrations early or late within the melt season [2]. The impact of a changing climate on contaminant fate in the physical environment of cold regions is likely to be amplified by the sensitivity of the cryosphere to relatively small temperature changes. In other words, it is not so much the actual change in temperature that will modify a contaminant’s environmental behaviour, but such modification will be brought about by changes in the extent and duration of a seasonal snow and sea ice cover and in the nature of the snow melt [4]. In order to anticipate the potential influence of climate change, it is necessary to improve the general understanding of contaminant-cryosphere interactions. Our ambition is to develop predictive capabilities to address questions such as: Which contaminants are most amplified during snow melt? What snow and melt conditions favour contaminant amplification in melt water? Such research may provide important insights into the extent to which future climate conditions exacerbate or attenuate contaminant amplification through snow.

2. Materials and methods We use a combination of laboratory experiments, field studies and computer simulations to get a detailed mechanistic understanding of the contaminant amplification processes occurring during snow melt. Artificially made and contaminated snow is subjected to controlled melting in a cold room laboratory. The frationated melt water samples are filtered and the sorbed and dissolved fractions analysed with appropriate trace analytical techniques [5,6]. For volatile analytes, such as semifluorinated alkanes and elemental mercury, the snow melt vessel is sealed and the headspace collected by pulling air through sorbent tubes with a pump [6,7]. Elution and volatilization curves for different contaminants of variable partitioning properties, for different types of snow (surface area, particle content, depth, density, ion composition), and for different melting conditions (surface vs. bottom melt, speed of melting, continuous melt vs. freeze-thaw cycles) are recorded, while snow properties are monitored with time domain reflectometry.

100cm

plexiglas lid rectangular stainless steel basin multiplexer 50cm 40cm TDR-probes cable tester

PC coolant in double bottom

Figure 1: Diagram and photograph of the snow melt vessel (right) and snow gun (left) used during laboratory experiments. Field studies in the highly urbanised Highland Creek watershed in Toronto involve the repeated sampling of river water throughout the snow melt season. Snow pack and groundwater samples have also been sampled for comparison. Sorbed and dissolved fractions are analysed by trace analytical techniques [8,9]. Elution curves of contaminants from a melting snow pack are predicted with a simple mass balance model that simulates the sequential melting of several horizontal snow layers and the resulting downward percolation of melt water. The model assumes equilibrium partitioning between the various snow pack phases (snow grain surface, partitculate matter, melt water, air-filled pore space) [10]. 3. Results and discussion Laboratory experiments revealed at least five types of elution curves for organic contaminants from a melting snow pack (Table 1) [11,13]. All types could be reproduced with, and thereby mechanistically explained by, the snow pack melt model [10,13].

Type Timing of release Contaminant characteristics Examples 1 early during melt water soluble atrazine, chlorothalonil, short chain perfluroinated acids 2 at the end of melt strongly sorbing to particulate matter (PM) or 4 to 5 ring PAHs, PCBs snow grain surfaces 3 late during melt somewhat water soluble and at the same long chain perfluorinated time high affinity for snow grain surfaces acids, chlorpyrifos 4 early during melt and partially dissolved in the aqueous melt water lindane, fluorene at the end of melting phase and partially sorbed to PM 5 in the middle of the sorption to snow grain surface decreasing intermediate chain melt during the melt perfluorinated acids Table 1: Types of snow pack elution behaviour observed in the laboratory. Elution curves in river water do not resemble those eluting from laboratory snow packs, except that water soluble contaminants tend to appear early during the melt period [8,9]. Particle-bound contaminant concentrations in the river tend to peak sharply during snow melt, and correlate with river run-off rates [8,9]. Contaminant transport in the river can increase by several orders of magnitude during the melt period [8].

4. Conclusions Concentration time profiles of particle bound contaminants in rivers during snow melt are less controlled by amplification processes occurring within the snow pack, and depend more on factors that determine run-off rate and the mode of melt water ablation from the snow pack to the stream (overland vs.subsurface flow). Factors that influence the run-off behaviour of such contaminants during snow melt include: rate of melting, snowpack depth, and the extent of water retention in the watershed (e.g. extent of soil freezing prior to formation of a snow cover, surface cover, relief). Many of these factors are influenced by a changing climate.

5. References [1] Wania F. 1999. On the origin of elevated levels of persistent chemicals in the environment. Environ Sci Pollut Res 6 : 11-19. [2] Meyer T, Wania F. 2008. Organic contaminant amplification during snowmelt. Water Res 42: 1847-1865. [3] Herbert, BMJ, Villa S, Halsall CJ. 2006. Chemical interactions with snow: understanding the behaviour of semi-volatile organic compounds in snow. Ecotoxicol. Environ. Saf. 63: 3-16. [4] Macdonald RW, Mackay D, Li YF, Hickie B. 2003. How will global climate change affect risks from long- range transport of persistent organic pollutants? HERA 9: 643-660. [5] Meyer, T, Lei YD, Wania F 2006. Measuring the release of organic contaminants from melting snow under controlled conditions. Environ Sci Technol 40: 3320-3326. [6] Mann E, Meyer T, Mitchell CPJ, Wania F. 2011. Mercury fate in ageing and melting snow: Development and testing of a controlled laboratory system. J Environ Monit 13: 2695-2702. [7] Plassmann M, Meyer T, Lei YD, Wania F, McLachlan MS, Berger U. 2010. Theoretical and experimental simulation of the fate of semifluorinated n-alkanes during snow melt. Environ Sci Technol 44: 6692–6697. [8] Meyer, T., F. Wania F. 2011. Transport of polycyclic aromatic hydrocarbons and pesticides during snowmelt within an urban watershed. Wat Res 45: 1147-1156. [9] Meyer, T, De Silva AO, Spencer C, Wania F. 2011. The fate of perfluorinated carboxylates and sulfonates during snowmelt within an urban watershed. Environ Sci Technol 45: 8113–8119. [10] Meyer T, F. Wania F. 2011. Modeling the elution of organic chemicals from a melting homogeneous snow pack. Wat Res 45: 3627-3637. [11] Meyer T, Lei YD, Muradi I, Wania F. 2009. Organic contaminant release from melting snow: I. Influence of chemical partitioning. Environ Sci Technol 43: 657–662. [12] Meyer T, Lei YD, Muradi I, Wania F. 2009. Organic contaminant release from melting snow: II. Influence of snow pack and melt characteristics. Environ Sci Technol 43: 663–668. [13] Plassmann M, Meyer T, Lei YD, Wania F, McLachlan MS, Berger U. 2011. Laboratory study on the fate of perfluorinated carboxylates and sulfonates during snow melt. Environ Sci Technol 45: 6872–6878. Acknowledgement - We thank our collaborators for their invaluable contribution to our work on contaminants and snow and the Canadian Foundation for Climate and Atmospheric Sciences (CFCAS) for funding. Climate change and Arctic marine mercury biogeochemistry – Conclusions and Research Needs from the AMAP 2011 Mercury Assessment

Peter Outridge 1,2, Gary Stern 2,3, Lisa Loseto 2,3, and Robie Macdonald 2,4

1 Centre for Earth Observation Science, University of Manitoba, Winnipeg R3T 2N2, Canada 2 Natural Resources Canada, Geological Survey of Canada, Ottawa K1A 0E8, Canada 3 Fisheries & Oceans Canada, Winnipeg R3T 2N6, Canada 4 Fisheries & Oceans Canada, Sidney V8L 4B2, Canada E-mail contact: [email protected]

1. Introduction The Arctic is especially vulnerable to global warming, with models and observations suggesting double the temperature rise compared to temperate or tropical regions. The biogeochemical cycle of Hg in the Arctic (Fig. 1) is particularly susceptible to climate change for a number of reasons [1]: • the Hg cycle is linked to the organic carbon cycle, both by affinity in transport and by methylating processes. Change in the cryosphere will lead to change in the organic carbon cycle; • natural and anthropogenic Hg inventories in the cryosphere may become unstable with warming; • Hg transport within, and exchange between, air, water, soils, sediments and biota is climate-sensitive; • Hg switches between chemical forms that exhibit widely differing volatilities, bioavailabilities and toxicities; • exposure of top predators to Hg can be affected both by bottom-up processes and top-down processes, most of which are themselves affected by climatic factors.

This review focuses on how the Arctic’s marine Hg cycle has been and is likely to be impacted by climate change. The marine system is of particular significance as it is here that most of the subsequent risks to humans and wildlife from Hg are developed through methylation, and because of the heavy reliance on marine animal hunting by most northern communities [2].

2. Major Findings and Conclusions (A Selection) A. Rising temperatures in the Arctic should slow net oxidation of atmospheric gaseous Hg(0) to aerosol Hg(II) during AMDEs, because of an increased HgBr2 dissociation and a reduction in release of Br radicals from sea ice. This effect would tend to decrease the rate of AMDE Hg deposition. Conversely, with further loss of permanent sea-ice, increases in halogen-rich first-year ice and so in reactive Br in the marine boundary layer may increase AMDE Hg deposition. B. Reduced sea ice will likely affect Hg dynamics across the air-seawater interface by: first, more Hg(II) aerosol deposited from air will land directly on seawater rather than on sea ice and so be less likely to be revolatilized; and second, rates of bi-directional exchange of GEM/DGM will be enhanced with possibly an increased net Hg loss. The overall effect may be nearly neutral. C. Several processes may increase net Hg methylation in the Arctic Ocean: longer ice-free seasons, and enhanced inputs of terrestrial nutrients, sulfate and carbon, leading to increased primary productivity and bacterial activity in sediments and the water column; and, increased inputs of inorganic Hg from coastal permafrost thaw, erosion or riverine fluxes. Some effects, such as elevated MeHg–DOM binding or photo- demethylation, may act to reduce dissolved MeHg and its uptake by marine food webs. D. In sea-ice dependent marine mammals such as beluga, polar bears and seals, ice-related changes in habitat selection, food chain length and feeding behaviour may affect dietary exposure to Hg.

3. Research Needs (A Selection) A. Uncertainty about the net effect of temperature increases on AMDE chemistry make it impossible to even qualitatively predict how rising average temperatures will impact on Br levels, and atmospheric Hg chemistry. Given the important role AMDEs play in THg inputs to the Arctic, additional laboratory and field investigations of temperature effects are warranted. B. Because the evasion of DGM from the ocean could become a major loss in the Hg budget of a warmer Arctic, further efforts to constrain the rate of marine Hg evasion should be undertaken. C. As net methylation rate is the key rate-limiting step link between the inorganic Hg forms which dominate the environment and toxic MeHg which biomagnifies in food webs, research in this area is a priority. D. The number and scope of studies examining marine biotic Hg – climate relationships needs to be expanded in terms of numbers of species and time span; sea-ice obligate marine mammals and fish may be most affected by climate change. E. Mass balance budgets for MeHg may be as revealing as were those for total (inorganic) Hg, but first require significantly greater effort in measuring MeHg masses and transformations.The recent measurement of marine methylation and demethylation rates in the Arctic Ocean [4] is a major step forward in understanding.

Figure 1. The cycling of mercury through the Arctic, emphasizing the connectivities between marine and terrestrial/freshwater systems, and between Arctic and southern latitudes.

4. References [1] Macdonald RW, Loseto LL. 2010. Are Arctic Ocean ecosystems exceptionally vulnerable to global emissions of mercury? A call for emphasized research on methylation and the consequences of climate change. Environ Chem 7:133–138. [2] AMAP. 2011. AMAP 2011: Arctic Mercury Science Assessment. Oslo, Norway: Arctic Monitoring and Assessment Programme, 193 p. [3] Stern GA, Macdonald RW, Outridge PM, Wilson S, Cole A, Chetelat J, Hintelmann H, Loseto LL, Steffen A, Wang F, Zdanowicz C. in press. How does climate change affect Arctic mercury? Sci Tot Environ. [4] Lehnherr I, St. Louis VL, Hintelmann H, Kirk JL. 2011. Methylation of inorganic mercury in polar marine waters. Nature Geoscience doi: 10.1038/NGEO1134.

Acknowledgement - The authors thank AMAP for permission to adapt Fig. 1 from a similar figure in their 2011 Assessment Report. Local contaminant sources in the Arctic: Volatile and non-volatile residues from combustion engines in surface soils from snow mobile tracks in the vicinity of Longyearbyen (Svalbard Norway)

Roland Kallenborn1,2, Norbert Schmidbauer3, Stefan Reimann4, Monika Trümper2, and Michael Tessmann5

1Norwegian Unviersity of Life Sciences (UMB), Dept. of Chemistry, Biotechnology and Food Science (IKBM, NO-1432 Ås, Norway. 2University Centre in Svalbard, Dept. of Arctic Technology, NO-9171 Longyearbyen, Svabard, Norway 3NILU- Norwegian Institute for Air Research, NO2027 Kjeller, Norway 4 Swiss Federal Laboratories for Material Sciences and Technology, EMPA, CH-8600 Dübendorf, Switzerland. 5. Sars International Centre for Marine Molecular Biology, NO-5008 Bergen, Norway

E-mail contact: [email protected]

1. Introduction

During a three-month monitoring campaign in 2007, very high atmospheric levels of benzene-toluene-xylene (BTX) related emissions were found in daytime along the main snowmobile routes in Longyearbyen during the late winter season 2007 (main tourist season) [1]. Total emissions of about 81 t/year were estimated for 2007 solely for snowmobile activities. 2-stroke engine driven vehicles are estimated to stand for around 92 % (74 t/a) of the hydrocarbon emissions alone although it is estimated that only 360 of the 1802 snowmobiles driven in 2007 on Svalbard are equipped with 2-stroke engine technology (Vestreng et al 2009). This study also concluded that around 51 % of the fuel leaves the 2-stoke engine unburned via the exhaust again when the snowmobile is driven. As benzene has also inherent carcinogenic properties, it is expected that persons driving snowmobiles on a regular basis or professional snowmobile guides could be exposed to considerable amounts of this complex chemical mixtures with the potential for effects on health and well being. Motivated in the above-described facts, a first survey on fuel residues (ie, polycyclic aromatic hydrocarbons = PAH, volatile organic carbons =VOC) in surface soil along the major winter snowmobile tracks on Nordenskiold-landet (Longyeardalen, Adventdalen, Sassendalen) has been performed during early summer 2010 [3] in order to investigate possible uptake of exhaust related pollution up-take into surface soil.

Materials and methods A total of 18 surface soil samples (V1-V20) and two surface snow samples (V2 and V V15) were collected for the analysis of polycyclic aromatic hydrocarbons (PAHs) along known and frequently used snowmobile tracks in/out of Longyearbyen (Latitude: 78° 13' 0 N, Longitude: 15° 37' 60 E). In Sassendalen (close to Longyearbyen), reference samples were collected close to the shore in not effected locations. In addition four surface soil samples were collected as transect across the frequently used snowmobile tracks. A continuously measuring monitoring device for the quantitative determination of Benzene- Toluene-Xylene (BTX) components in ambient air was installed and conducted in the University Centre in Svalbard (UNIS) Laboratory facilities in 2010 during two measuring periods in spring 2010 (07 April to 11 May) and in autumn 2010 (05 September to 25 October). All samples were analysed in duplicates. The anaysis of 15 PAH isomers were performed on a gas chromatograph coupled to a mass selective detector (GC/MS = Trace GC, PolarisQ low resolution ion trap mass spectrometer, Thermo Fisher, USA) A 10m of uncoated fused silica guard column was mounted in front of a DB-5MS + 10m Duraguard capillary column (30m x 0.25 mm x 0.25 µm, J&W Scientific). FLuorene (Fl), Phenanthrene (Phe), Anthracene (Anth), Fluoranthene (Flu), Pyrene (Pyr), Benz(a)anthracene (BaA), Triphenylene (Tri), Chrysene (Chr), Benzo(b)fluoranthene (BbF), Benzo(k)flouranthene (BkF), Beno(e)pyrene (BeP), Benzo(a)pyrene (BaP), Indeno(123cd)pyrene (IP), Dibenzo(h)anthtracene (DahA), and Benzo (Ghi)perylene (BgP) were selected as trget PAHs. Total concentrations for 15 PAHs were determined in all 18 soil samples (V-1 to V20, see table 1). Table 1: SUM 15 PAHs in all soil samples from snow mobile tracks in Longyearbyen (2010) Samples conc. [ng/g dw] Samples conc. [ng/g dw] V-1-1 1495.2 V-11-1 336.8 V-3-1 1382.8 V-12-1 176.4 V-4-1 1662.6 V-13-1 360.4 V-5-1 21.4 V-14-1 70.2 V-6-1 304.4 V-16-1 536.4 V-7-1 528.5 V-17-1 95.6 V-8-1 1883.1 V-18-1 104.2 V-9-1 368.6 V-19-1 286.4 V-10-1 138.9 V-20-1 126.8

Results and discussion Samples site V1, V3, V4 and V8 are characterized by PAH sum levels above 1300 ng/g dw. (Hot spots) All “hot spot” samples are characterized by predominant Phe and Chr concentration (ratio 1:1). Except for sample V-3-1 (Longyearbreen glacier morraine), where Phe is the overall predominant PAH compound. Source elucidation based upon PSH pattern examination confirmed that pyrogenic sources as the predominant contribution of the elevated PAH levels. The highest PAH concentratins were found in sample V-8, close to a former airfield in the Advent valley in Longyearbyen. This elevated value is clearly caused by emission and subsequent deposition of PAH from fossil fuel driven engines and the subsequent deposition on the surface snow and finally on the underlying soil. The sample is dominated by a pyrogenic PAH patterns However, as possible long-term exposure source and potential contribution, PAH remaining from technical installations/ spills at the former winter airfield, operated in this location on frozen ground until the early 1970s, cannot be excluded and should, thus, be explored in more detail during future research activities. As major indicator for the anthropogenic emissions from fossil fuel engine driven vehicles (snow mobiles), benzene (C6H6) was analysed. Compared to the 2007 emission data, a significant reduction of the benzene levels was identified (30% of the 2007 levels observed). The comparison is presented in figure 1. As already seen in the 2007 data, also for winter/spring 2010, an expressed daily pattern distribution with elevated levels in morning and evening was observed.

Figure 1: Benzene level (parts per billions =ppb) comparison between the 2007 (red) and 2010 (blue) sampling campaign.

2. Conclusions

In comparison to the 2007 BTX ambient air monitoring campaign a significant reduction of the BTX emissions was found for the snowmobile season (April/May 2010). Only max 30% of the 2007 concentrations were detected for Benzene in L2010 Longyearbyen air. This significant concentration mainly caused by two major reasons 1.)Reduced activities of continuous heavy-duty vehicle related traffic on the road to/from Mine No. 7 since the coal- cleaning facilities in the harbour was decommissioned in 2009 and the mine was not operated in the monitoring period. 2) Higher proportion of 4-stroke engine driven snowmobiles during the 2010 season and the associated reduced emission of BTX due to higher efficacy of the 4-stroke engines. Polycyclic aromatic hydrocarbons (PAH) was determined in all 18 surface soil samples in the concentration range between 21 and 1883 ng/g dw (dry weight, SUM 15 PAH). All samples were characterized with pyrogenic PAH patterns obviously dominated by PAHs released from fossil fuel combustion (diesel/ gasoline driven engines). The highest concentrations were found in a soil samples collected at the former winter airfield close to the old Northern Light observatory. It is thus concluded that although effective weathering processes continuously reduce the emitted and deposited PAH concentration in the soil, the most recalcitrant compounds remain in the surface soil with the inherent potential to accumulate in biota (vegetation and organisms).

3. References [1] Reimann S, Kallenborn R, Schmidbauer N. 2009. Severe Aromatic Hydrocarbon Pollution in the Arctic Town of Longyearbyen (Svalbard) cause by snowmobile emissions. Environ. Sci. Technol. 43: 4749-4795. [2] Vestreng V, Kallenborn R, Økstad E. 2009. Climate influencing emissions, scenario and mitigtion options at Svalbard. Climate and Pollution Directorate, Norway (KLiF). TA 2552/2009. 56 p. [3] Kallenborn R, Schmidbauer N, Reimann S. 2010, Volatile and persistent emissions from traffic and power production on Svalbard (VETAPOS). Report to the Environmental Fund, at the Governor of Svalbard, Longyearbyen. 26. Acknowledgement - The authors thank Emma Johansson-Karlsson (UNIS), Pernilla Carlsson (UiT/UNIS) and Tatiana Drotikova (UNIS) for logisitical support and help during the prepartion of the sample si the UNIS laboratories

The Impact of Thawing Permafrost on Lakes of the Mackenzie Delta uplands, NT, Canada

Jules M. Blais1, Adam Houben1, Todd French2, Ramin Deison1, Linda E. Kimpe1, Michael Pisaric3, Steve Kokelj4, Joshua R. Thienpont2, John P. Smol2

1University of Ottawa, Ottawa, ON, Canada, K1N 6N5 2Queen’s University, Kingston, ON, Canada, K7L 3N6 3Carleton University, Ottawa, ON, Canada, 4 Aboriginal Affairs and Northern Development Canada, Yellowknife, NT, Canada, X1A 2R3 E-mail contact: [email protected]

1. Introduction

Total permafrost in the Northern Hemisphere currently occupies an area of ~26 million km2, and by 2100, this area is expected to decrease by 19-35% [1]. In the Mackenzie Delta, NWT, temperatures are projected to rise by 4 to 5°C in the next 50 years. Over the past 20 years, mercury and PCBs have been steadily rising in burbot (Lota lota) from the Mackenzie River [2], despite stable or decreasing concentrations of these chemicals in the atmosphere, prompting speculation on how the changing thermokarst environment and atmospheric environment might be affecting contaminant cycles.

Here we tested the hypothesis that the presence of retrogressive thaw slumps in the Mackenzie Delta uplands (north of Inuvik, NT, Canada) is affecting nutrients (total and dissolved nitrogen (N) and phosphorus (P), persistent organic pollutants, metal concentrations, and algal community assemblages in small tundra lakes.

2. Materials and methods We sampled water from 28 lakes in regions affected by thermokarst processes of the Mackenzie Delta Uplands, NT, Canada, using a case-control comparison of lakes where retrogressive thaw slumps were present and absent (Figure 1). Lake sediment cores were collected from 14 of these lakes, also using a case-control comparison as described above. Water was sampled by helicopter in July of 2009, 2010, and 2011 following methods described in [3, 4]. Sediment cores were collected in April 2007 and July 2008, radiometrically dated by 210Pb, 137Cs, and 226Ra, and analyzed for metals and persistent organic pollutants using methods in [3]. Figure 1: Study site locations in the Mackenzie Delta Uplands, NT. Lakes identified as ‘a’ are 3. Results and discussion reference lakes and ‘b’ lakes have pronounced thaw slumps as shown in photo (inset). 3.1. Surface sediments The sediment lithology was fairly homogenous in our 14 cores, grading from light brown or dark brown to black sediment at the bottom. However, surface sediments from slumped lakes (i.e. those with thaw slumps) tended to be greyer in colour, likely due to weathering of exposed clays from thaw slumps [5]. Focus-corrected sedimentation rates in slumped lakes (269±66 SD g m-2 yr-1) were more than double those in reference lakes (120±37 g m-2 yr-1) indicating higher incoming material to lakes disturbed by these retrogressive thaw slumps. Slumped lakes had significantly lower total organic carbon content and higher sedimentation rates than reference lakes, suggesting that accelerated deposition of inorganic sediments from retrogressive thaw slumps diluted the sedimentary organic carbon. Mercury concentrations were higher in surface sediments of reference lakes (0.12-0.30 µg/g dw) than slumped lakes (0.07-0.12 µg/g dw), (t = 4.99, p<0.01), indicating dilution of mercury by rapid inorganic sedimentation following thaw slump development.

3.2. Lake water We compiled lake water chemistry data from 28 lakes chosen along a transect east of the Mackenzie Delta, from Inuvik to Richards Island. In general, when compared with the set of reference lakes without thaw slumps, slumped lakes had higher dissolved ions (Ca, Mg, Na, K, SO4, Cl, HCO3), higher pH, lower dissolved organic carbon, lower total phosphorus, and lower chlorophyll a. In addition, slumped lakes had lower total Hg and lower methyl Hg concentrations than reference lakes, possibly due to the higher pH and lower dissolved organic carbon found in slumped lakes, which reduce the solubility and delivery of Hg to lakes, respectively. In particular, we were able to directly apportion the influence of thaw slump disturbance on mercury dynamics by relating mercury concentrations in water to the proportional area of the lake’s catchment occupied by thaw slumps. This is the first clear demonstration to our knowledge of the influence of thaw slump development on contaminants in lakes. We also observed lower methyl mercury in thaw slump lakes than reference lakes, which runs counter to our predictions because we anticipated that deeper microbial active layers in soils from permafrost thawing and higher sulphate concentrations may contribute to increasing methyl mercury production in these systems, but this does not appear to be the case.

4. Conclusions

This study provides compelling evidence that thawing permafrost near lakes of the Mackenzie Delta uplands are not responsible for the rising trend in mercury concentrations of fish in the Mackenzie River.

5. References [1] ACIA 2005. Arctic Climate Impact Assessment. Cambridge University Press, Cambridge, United Kingdom, 1042. [2] Carrie, J., Wang, F., H, S., Macdonald, Robie W, Outridge, P. M., and Stern, Gary A. (2010). Increasing Contaminant Burdens in an Arctic Fish, Burbot (Lota lota), in a Warming Climate. Environ. Sci. Technol. 44: 316-322. [3] Michelutti, N., Liu, H., Smol, J.P., Kimpe, L.E., Keatley, B., Mallory, M., Douglas, M.S.V., Blais, J.M. 2009. Accelerated delivery of polychlorinated biphenyls (PCBs) in recent sediments near a large seabird colony in Arctic Canada. Environ Pollut. 157: 2769-2775. [4] Brimble SK, Foster KL, Mallory ML, Macdonald RW, Smol JP, Blais JM. 2009. High Arctic ponds receiving biotransported nutrients from a nearby seabird colony are also subject to potentially toxic loadings of arsenic, cadmium and zinc. Environ. Toxicol. Chem. 28: 2426-2433. [5] Kokelj, S. V., and Burn, C. R. 2005. Geochemistry of the active layer and near-surface permafrost, Mackenzie delta region, Northwest Territories, Canada. Canadian Journal of Earth Sciences 42: 37-48.

Acknowledgement - The authors thank the Natural Sciences and Engineering Research Council (Canada), the Polar Continental Shelf Program, and the Northern Scientific Training Program for financial support,

Burdens and inputs of perflourinated compounds in the Lomonosovfonna Ice Core, Svalbard (2009).

Mark H. Hermanson1, Pim Leonards2, Elisabeth Isaksson3, Margit Schwikowski4

1University Center on Svalbard, N-9171 Longyearbyen, Svalbard 2VU University, 1081 HV Amsterdam, Netherlands 3Norwegian Polar Institute, N-9296 Tromsø, Norway 4Paul Sherrer Institute, 5232 Villigen PSI, Switzerland ______

1. Introduction

Ice cores have proven to be excellent for measurement inputs of persistent trace organic contaminants delivered long distances through the atmosphere. Svalbard, which is ~60% covered with permanent ice, has several sites with thick enough ice for retrieving ice cores covering the period of high production or persistent organic contaminants (often called POPs, for persistent organic pollutants). Our previous work on Svalbard has found significant amounts of various current-use and legacy contaminants [1], documenting the history of inputs and burdens within the ice core, the latter indicating the mass of contaminant stored in the region.

2. Materials and methods

2.1 Ice core drilling In March 2009, we drilled a 37-meter ice core representing ~1938 – 2008+ from Lomonosovfonna (78°49' 24.4" N; 17°25' 59.2"E), the highest elevation glacier on Svalbard (1202 m.a.s.l.). The ice core was transported to Polarmiljøsenteret (now Framsenteret) in Tromsø, Norway where it was stored frozen. In March 2011, the core was sectioned in a freezer. For PFC analysis, we took a vertical slice down core not thicker than 1 cm, melted the ice and stored in non-teflon bottles. Target volume was 250 – 300 mL (actual average volume = 291 mL). We collected 27 samples from this core, with an average resolution in the top 21 meters of 2.4 years per sample from 1976 – 2008. Because of the low volume requirement in comparison to analysis of pesticides, flame retardants or other industrial chemicals, our dating resolution was excellent.

2.2 PFC analytical methods We analyzed 12 PFC compounds, including PFBA, PFPeA, PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUnA, PFBS, PFHxS, PFOS, 6:2FTS in the top 14 samples of the core. Internal standards (13C and 18O PFCs) were added to 100 ml ice core water. The PFCs were extracted using solid phase extraction (SPE, Oasis WAX 6cc Cartridge, Waters). The SPE was conditioned and the sample loaded (100 ml). After a washing step, PFCs were eluted with CH3OH/NH4OH. The extract was dried and reconstituted with 0.1 ml MeOH containing three 13C-labelled injection standards. The final extract was analysed with LC-MS-MS (LC-QQQ) (Agilent) using a FluoroSEP-RP Octyl column (ES Industries). Retention time, parent and daugther ions of the PFCs were used for identification. External calibration was used. Some ion suppression experiments were conducted to investigate the importance on the response.

3. Results Lab results were reported as pg L-1. We calculated a burden (pg cm-2) knowing the mass inputs of liquid; flux (pg cm-2 yr-1) was calculated knowing the years of accumulation for each sample, calculated using the Nye model [2].

Five compounds were not detected in any segment of the core, including PFBA, PFPeA, PFHpA, PFBS, 6:2FTS. PFNA dominated the accumulated burden in the core (Figure 1), showing 29.4 pg cm-2, 81% more than the second highest, PFOA, 16.2 pg cm-2. It is thought that the PFNA and PFOA may be an atmospheric oxidation products of 8:2 FTOH which has been found to be the dominant gas-phase PFC in

PFNA flux, pg cm-2 yr-1

0 1 2 3 4 5 6 0

-2008 Figure 1. PFNA flux profile in the Lomonosovfonna ice core

-2006 (2009). PFNA had the greatest

5 burden of 12 PFCs in the ice -2003 -2 core (29.4 pg cm ). The -2002 increase in the surface layer -2000 was also seen in PFOA, PFDA and PFOS profiles. 10 -1997 -1995

Depth, meters Depth, -1993 -1990 15 -1987 -1985 -1982 -1979 20 -1976

Europe. PFOA however, is considered to be the dominant PFC in the atmospheric particle phase in Europe; these results suggest that PFCs in both phases are reaching high-elevation ice on Svalbard. Other burdens include PFHxA and PFDA which were approximately equal (9.91 and 9.85 pg cm-2) and about one-third PFNA. No other PFC had a burden greater than 5.8 pg cm-2 (PFOS), including PFUnA, PFHpA and PFHxS. The dominance in burden by PFNA and PFOA is consistent with relatively high concentrations of these PFCs observed in polar bear liver from Greenland [3].

Net flux trends greater than 10 years duration appeared for PFNA, PFDA, and PFOS. The trend for PFNA begins in 1982 (0.388 pg cm-2 yr-1), increasing regularly until 1995 when it doubled to 1.25 pg cm-2 yr-1 by 1997, and reaching 5.5 pg cm-2 yr-1 by 2008 (Figure 1). PFDA has the longest record beginning with 0.10 pg cm-2 yr-1 in 1976, increasing and decreasing in no predictable pattern, leveling at ~ 0.4 pg cm-2 yr-1 after 2000 before increasing rapidly to 1.31 pg cm-2 yr-1 in 2008. PFOS has an irregular flux beginning with 0.24 pg cm-2 yr-1 in 1982, never exceeding 0.29 pg cm-2 yr-1 by1995 before increasing to 1.23 pg cm-2 yr-1 in 2008. Although PFOA has the second-highest burden, its short record begins with 0.77 pg cm-2 yr-1in 1990, doubling to 1.69 pg cm-2 yr- 1 by 1993, but not observed again until 2002 when it dropped by nearly 4 times (0.46 pg cm-2 yr-1). It nearly doubled by 2006, and increased by > 4x by 2008 (3.93 pg cm-2 yr-1).

4. Conclusion PFC are reaching the Lomonosovfonna glacier on Svalbard by long-range atmospheric transport. Burdens are dominated by PFNA and PFOA. PFDA, PFNA and PFOS have the longest flux histories (from 1976 for PFDA). The fluxes of all three are irregular over time, but all increased between 2006 and 2008, PFOS showing the largest increase (6 times). These increases may result from changes in climate or source patterns.

5. References [1] Ruggirello, R. M., Hermanson, M. H., Isaksson, E., Teixeira, C., Forström. S., Muir, D. C. G., Pohjola, V., van de Wal, R., Meijer, H. A. J. Current-use and legacy pesticide deposition to ice caps on Svalbard, Norway. J. Geophys. Res. – Atmos. 2010, 115, D18308, doi:10.1029/2010JD014005 [2] Nye, J. F. 1963. The response of a glacier to changes in the rate of nourishment and wastage. Proceed. Royal Soc. A275 (1360), 87-112. [3] Ellis, D. A.; Martin, J. W.; De Silva, A. O.; Mabury, S. A.; Hurley, M. D.; Andersen, M. P. S.; Wallington, T. J. Degradation of fluorotelomer alcohols: a likely atmospheric source of perfluorinated carboxylic acids. Environ. Sci. Technol. 2003, 38, 3316-3221. The deposition and fate of perfluorinated alkyl substances (PFAS) in the Norwegian Arctic snowpack

Olivier RA Bertrand1, Crispin J Halsall1, Dorte Herzke2, Sandra Huber2, Tore Nordstad3, Sabino del Vento1 and Eldbjørg S Heimstad2

1Centre for Chemicals Management, Lancaster Environment Centre, Lancaster University, LA1 4YQ, Lancaster, UK 2Norwegian Institute for Air Research (NILU), Department of Environmental Chemistry, Fram Centre, Hjalmar Johansens gate 14, NO-9296, Tromsø, Norway 3Norwegian Polar Institute (NPI), Fram Centre, Hjalmar Johansens gate 14, NO-9296, Tromsø, Norway E-mail contact: [email protected]

1. Introduction Poly- and perfluorinated alkyl substances (PFAS) are man-made chemicals that are ubiquitous in the environment and are present in humans and wildlife [1, 2]. These chemicals occur in the Arctic through long- range transport processes with the perfluorinated acids (PFAs) [e.g. carboxylates (PFCAs) and sulfonates (PFSAs)], present in sentinel organisms such as the polar bear (Ursus maritimus) and the ringed seal (Phoca hispida). PFAs are present in arctic media through a number of processes, including transport with ocean currents, oxidative degradation of ‘neutral’ precursors (e.g. fluorotelomer alcohols) in the atmosphere and possibly transport with airborne particles and aerosols. A combination of these processes results in their deposition with snowfall, although only a few studies to date have examined accumulation of these chemicals in the Arctic snowpack [3]. Questions arise regarding the sources of these chemicals in atmospheric deposition in remote locations [3] and the role of snow in delivering PFAs to catchment systems during periods of melt [4]. In this study, a detailed examination of PFAS was undertaken in the seasonal snowpack at remote terrestrial sites in Northern Norway. The purpose was to investigate, in some detail, their accumulation in different snow layers and to relate their profile and concentrations to physical and chemical characteristics of the separate snow layers as well as their accumulation history.

2. Materials and methods Air and snow sampling was carried out in Northern Norway within and close to Dividalen national park (~140 km from the town of Tromsø) during March 2011. Three sampling sites were selected. The two southernmost sites (spaced by around 20 km) were located in the same valley [one at Frihetsli meteorological station (68° 46’N, 19° 42’ E, named Frihetsli thereafter) and the other close to Holt (68° 57’N, 19° 28’ E), both in Dividalen] orientated SSE-NNW respectively. A third site was located in Kjosen fjord [Lyngen-URA meteorological station (69° 35’N, 20° 05’ E, named Lyngen thereafter) for snow and precipitation], orientated WNW-ESE, around 70 km north from Holt. At each site, separate snowpack layers were identified and sampled for PFAS (n = 30) as well as sub- samples taken for basic chemical and physical measurements, including major ions, pH, conductivity, particle concentrations. Snow sampling for PFAS took place approximately every two days at the various sites. Snow was collected in 25 L tap-fitted polypropylene buckets using a solvent-rinsed shovel. High- volume air samples were also collected at the Frihetsli site with each sample comprising of a 20.3 cm x 25.4 cm GF/A glass-fiber filter (pore size: 1.6 µm) and polyurethane foam (PUF) plug – XAD-2 resin sandwich, to collect particle-bound and vapour phase PFAS, respectively (n = 2). River water was sampled in Frihetsli to establish baseline levels of PFAS in nearby surface waters. Snow samples were melted at room temperature, with 2 L of meltwater (transferred to polypropylene or polyethylene bottles) used for PFAS analysis and ~45 mL used for other chemical and physical measurements. The meltwater samples were filtered on pre-baked and weighed 47 mm diameter GF/F filters spiked with isotopically labelled PFAS internal standards, and the filtrate eluted through pre-conditioned Oasis WAX cartridges. The cartridges were then eluted with 6 mL of methanol and 8 mL of 0.1% ammonium hydroxide in methanol, whereas the filters were sonicated in 3 steps of 4 mL of methanol. Procedural blanks followed the same protocol for filters and filtrates. The extracts were concentrated and subject to clean up with 25 mg ENVI-Carb and 50 µL glacial acetic acid [5]. PFAS were analysed on a Thermo Scientific UHPLC-MS/MS system (operating in ESI). Compound separation was achieved on a Waters Acquity UPLC HSS 3T column (2.1 × 100 mm, 1,8 µm) using NH4OAc-buffered 90:10 methanol/water mobile phase. Quantification was conducted with the internal standardisation method based on the response of representative isotope-labelled PFAS. 3. Results and discussion Air mass trajectory analysis was used to examine air mass origins for specific air samples and snowfall events, while in the snowpack the vertical evolution of snow characteristics are studied to help understand sources of PFAS to fresh snowfall and their fate during snow ageing. While PFAS data are pending, Figure 1 illustrates the pH and conductivity profiles of the sampled snow layers for PFAS analysis. Clearly, there are marked differences in pH between these snow layers which is also reflected in the major ion content and conductivity demonstrating the influence of different air masses and sources on separate snowfall events.

Figure 1: Evolution of pH and conductivity profiles against time in the snow layers sampled in Lyngen, Holt and Frihetsli. Layer N was the top layer of each snowpack on the 13th of March. N+1 and N+2 represent fresh snow layers and their evolution whereas N-1 and N-2 stand for underlying adjacent layers. N.B.: Bottom layer is separated from N-2. Rising air temperatures modified snow temperature profiles and gradients at all sites on the 19th of March and this may affect PFAS deposition and fate. Figure 2 shows differences between snow crystals representative of two fresh snowfalls: 14th of March, dendritic snow; 19th of March, wet snow.

Figure 2: Photographs of fresh snow crystals. Left: 14th of March, dendritic snow. Right: 19th of March, wet snow. Grid is 1 mm.

4. Conclusions

The work oulined here presents a detailed examination of specific snowfall events and air mass origins on

PFAS accumulation in the seasonal snowpack. Importantly, the chemical and physical properties of separate snow layers are used to investigate PFAS behaviour, and the role of particle matter in depositing and accumulating these chemicals in both fresh snowfall and in deeper layers.

5. References [1] Giesy JP, Kannan K. 2001. Global distribution of perfluorooctanesulfonate in wildlife. Environ Sci Technol 35:1339-1342. [2] Prevedouros K, Cousins IT, Buck RC, Korzeniowski SH. 2006. Sources, fate and transport of perfluorocarboxylates. Environ Sci Technol 40:32-44. [3] Young CJ, Furdui VI, Franklin J, Koerner RM, Muir DCG, Mabury SA. 2007. Perfluorinated acids in arctic snow: New evidence for atmospheric formation. Environ Sci Technol 41:3455-3461. [4] Meyer T, De Silva AO, Spencer C, Wania F. 2011. Fate of perfluorinated carboxylates and sulfonates during snowmelt within an urban watershed. Environ Sci Technol 45:8113-8119. [5] Powley CR, George SW, Ryan TW, Buck RC. 2005. Matrix effect-free analytical methods for determination of perfluorinated carboxylic acids in environmental matrixes. Anal Chem 77:6353- 6358.

Acknowledgement - The authors thank the Norwegian Meteorological Institute for access to Frihetsli, Norwegians for welcome on their land and EU 7FP project ‘ArcRisk’ (grant agreement 226534) for funding. Spatial and temporal trends of persistent organic pollutants and mercury in ringed seals from the Canadian Arctic

Derek Muir1, Xiaowa Wang1, Amy Sett1, Enzo Barresi2, Ed Sverko2, Steve Ferguson3, Michael Kwan4

1Environment Canada, Aquatic Ecosystem Protection Research Division, Burlington ON Canada 2National Laboratory for Environmental Testing, Environment Canada, Burlington ON Canada 3Dept of Fisheries and Oceans, Arctic Aquatic Research Division, Winnipeg MB Canada 4Nunavik Research Centre, Makivik Corp., Kuujjuaq Qc Canada

E-mail contact: [email protected]

1. Introduction The ringed seal is the most abundant Arctic pinniped with a circumpolar distribution and has been a key biomonitoring animal for examining spatial and temporal trends of persistent organic pollutants (POPs) and mercury (Hg) in the Arctic since the 1970s [1]. Because of their high abundance, ubiquitous distribution, and central position in the food web, ringed seals play an important role in the dynamics of arctic marine ecosystems. The goal of this ongoing study is to determine temporal trends of legacy POPs, new/emerging POPs, as well as Hg in Canadian Arctic ringed seals using annual collections at Arviat, Resolute, and Sachs Harbour as well as less frequently at nearby communities (see footnote Table 1). The study builds on results for legacy POPs and Hg going back to the 1980s, and earlier in some cases, with a database consisting of results for about 700 samples for PCBs and organochlorine pesticides (OCPs) in ringed seal blubber and about 1000 samples for Hg in liver and muscle, along with associated biological data for each animal. Results for new POPs, polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), other brominated flame retardants (BFRs), perfluorinated chemicals (PFCs), and endosulfan, along with carbon and nitrogen stable isotope data, have been added to samples collected since 2001 and on selected archived samples from the 1970s and 1990s.

2. Materials and methods Sample collections are carried out by hunters each year (June-October) as part of their traditional hunting. Each year the collection consists of 10 to 25 adult ringed seals (blubber, liver, muscle, tooth/lower jaw for aging). Hunters are provided with a sampling kit and are asked to record length, girth, blubber thickness at the sternum, and sex as well as to place samples in prelabelled clear plastic bags. For neutral POPs only blubber of females and juveniles are analysed to limit the influence of age. For Hg muscle and liver samples are analysed, while PFCs are also determined in liver. Analytical methodology for organochlorine pesticides (OCPs), PCBs, PBDEs, other BFRs and endosulfan in seal blubber has been described previously [2]. PFCs were determined in seal livers by acetonitrile extraction and clean up on a carbon cartridge followed by LC-MS/MS [3]. Seal muscle was analysed for Hg by DMA. For liver, Hg was determined CV-AAS. QA steps included the analysis of NIST reference materials for POPs (SRM 1588a/b, 1946, 1974) and heavy metals (NRC DOLT-2, DORM-2, TORT-2). Reagent blanks were run with each batch of samples. All results were blank subtracted. All contaminants data were log10 transformed and geometric means (back transformed log data) were calculated. Temporal trends of PCBs and OCPs in the data for female ringed seals were analysed using the statistical program PIA [4]. Comparison of temporal trends in Hg concentrations was limited to animals of ≥ 5 yrs because concentration there was no significant relationship between age and Hg for these animals.

3. Results and discussion Mercury: Highest Hg concentrations in seal muscle are found in western and Central Arctic (Fig. 1A). A similar pattern is seen for Hg in liver (not shown). No significant increase or decline of Hg in seal muscle was found over a 7 – 9 year period at Arviat, Resolute and Sachs Harbour (Fig. 1B). δ13C and δ15N in seal muscle varied only over a narrow range (±0.5 ‰) indicating little change in diet over the same period and the average age of the animals sampled . Hg concentrations in liver were more variable at the same locations over the same period. This was not related to diet ( δ13C and δ15N) or to age but could reflect more recent diets of individual animals compared to measurements of muscle nitrogen. Fig 1. A. Geometric A B mean concentrations (± 1.5 95% CI) of Hg in muscle 1.0 Arviat Resolute of ringed seals from 13 Grise Fiord 0.5 Sachs Harbour locations in the Canadian Arctic. B. Sachs Resolute 1.0 Harbour Pond Inlet 0

Temporal trends of Hg Arctic Bay Partsper million (wetwt) Ulukhaktok at 3 locations Qikiqtarjuaq Pangnirtung (Geomeans ± 95% CI) Gjoa Haven 0.5

Kangiqsual Mercury, parts per million Arviat 0.0 ujjuaq Nain Inukjuaq Legacy POPs: Time trends of POPs were assessed in 4 regions (Table 1) using the PIA statistical program. We combined data for nearby communities because statistical analysis showed that concentrations of most PCB/OC pesticides were similar for nearby communities while differing significantly among regions. Overall, there are declining trends with the relative magnitude of ΣDDT> αHCH>Σ10PCB> ΣCHL. β-HCH is actually increasing in the Beaufort Sea and Lancaster Sound seals and declining significantly only in Hudson Bay. Largest declines of all legacy POPs are in Hudson Bay possibly reflecting proximity to source regions in eastern and central North America. Table 1. Results of analysis of time trends of POPs in ringed seal blubber using the PIA program [4] Region yrs α-HCH β-HCH HCB ΣPCB ΣDDT ΣCHL Hudson Bay1 12 % decline or increase -9.7 -4.3 -3.3 -4.9 -7.5 -8.4 1986-2010 r2 0.73 0.20 0.58 0.49 0.68 0.69 Lancaster2 16 % decline or increase -3.6 5.0 -0.87 -2.1 -2.8 0.98 1972-2010 r2 0.56 0.62 0.17 0.44 0.62 0.13 East Baffin3 6 % decline or increase -6.2 1.0 -1.6 -1.8 -3.1 -4.3 1986- 2006 r2 0.88 0.05 0.38 0.18 0.61 0.81 Beaufort Sea4 7 % decline or increase -1.2 5.8 -0.63 -0.34 -2.6 0.67 1972- 2010 r2 0.16 0.92 0.33 0.03 0.47 0.04 1 Arviat + Inukjuaq; 2 Resolute Bay + Arctic Bay + Grise Fiord; 3 Qikiqtarjuaq and Pangnirtung 4Sachs Harbour + Ulukhaktok (2001 & 2006)

New POPs: PBDEs, PFOS, and perfluorocarboxylates show increasing concentrations in the 1990s to early 2000s and then recent declines. Endosulfan and hexabromocyclododecane are present at low concentrations in seal blubber (0.01-2.0 ng/g) and appear to be increasing in concentration over the period 2005-2010.

4. Conclusions

Temporal trends of legacy POPs in the Canadian arctic generally show declining trends, except for β-HCH; this is similar to observations for other species and locations e.g. East Greenland and Alaska. However trends for new POPs differ from those in Greenland particularly for PFCs. Proximity to source regions and the influence of ocean transport through the Canadian archipelago may be the reasons for these differences. Continued annual sampling is improving the statistical power of the study and enabling testing of factors influencing trends of POPs and Hg including climate, diet and changes in global emissions.

5. References [1] de Wit CA, Fisk AT, Hobbs KE, Muir DCG, Gabrielsen GW, Kallenborn R, Krahn MM, Norstrom RJ, Skaare JU. 2004. AMAP Assessment 2002: Persistent Organic Pollutants in the Arctic Oslo, Norway. [2] Muir DCG, Backus S, Derocher AE, Dietz R, Evans TJ, Gabrielsen GW, Nagy J, Norstrom RJ, Sonne C, Stirling I and others. 2006. Brominated flame retardants in polar bears (Ursus maritimus) from Alaska, the Canadian Arctic, East Greenland, and Svalbard. Environ. Sci. Technol. 40(2):449-455. [3] Powley CR, George SW, Ryan TW, Buck, RC. 2005. Matrix Effect-Free Analytical Methods for Determination of Perfluorinated Carboxylic Acids in Environmental Matrixes. Anal. Chem. 77: 6353-6358. [4] Bignert A. 2007. PIA statistical application developed for use by the Arctic Monitoring and Assessment Programme. (available from www.amap.no). Arctic Monitoring and Assessment Programme Oslo, No, 13 Exposure of persistent organic pollutants in avian top predators in a changing northern climate Jan Ove Bustnes1

1 Norwegian Institute for Nature Research, FRAM – High North Research Centre on Climate and the Environment, N-9296 Tromsø, Norway

E-mail contact: [email protected]

1. Introduction Top predators in the Arctic ecosystem are the final destination of bioaccumulative POPs and mercury, and in such organisms the negative impacts are most likely to occur. However, little is known about how climate change will affect the accumulation of POPs in top predators [1]. Changes in POPs in arctic top predators may occur by two pathways: 1) directly through increased POP transport or 2) indirectly through changes in POP uptake through the food chain and changes in diets and physiology of top predators [2, 3, 4]. The importance of these pathways is little understood, and the aim of this presentation is to discuss how changes in climate and feeding ecology may affect the exposure of POPs in different avian top predators.

2. Materials and methods In this presentation different climate variables such as North Atlantic Oscillation index (NAO), the Arctic Oscillation index (AO), temperatures, snow conditions, precipitation etc. were related to annual alterations in concentrations of different legacy POPs (PCB, DDE etc) in three species of northern top predators. In addition feeding conditions were included for a terrestrial predator. The species studied included a top predator in the arctic pelagic food chain (the glaucous gull), one in the benthic food chain (the common eider) and one terrestrial top predator in Central Norway (the tawny owl).

3. Results and discussion It was found that in the arctic glaucous gull there were surprisingly strong positive relationships between large scale climatic indicators, such as the AO, in the year preceding measurement and concentrations of several POPs in the blood. In addition compounds with high long-range transport potential (HCB) showed stronger relationships than those with less potential (PCB). This suggests that transport of POPs in a changing climate might be important for exposure in this species. For the common eider it was found that low temperatures in the Arctic led to high lipid metabolism which increased the amounts of POPs in the blood during incubation fast, a situation different from subarctic eiders breeding in more benign environments. This suggests that changes in local climate may be of importance. For example a warmer Arctic may lead to lower circulating levels of POPs in this benthic feeding species. Finally, it was shown that in tawny owls the concentrations of POPs in eggs were related both to NAO and feeding conditions. However, it was found that the effect of feeding condition was dependent on climate; i.e. when winter climate conditions were poor (cold weather) feeding condition played a significant role, whereas in good condition no such effects were found.

4. Conclusions

This review of studies of different species suggests that climate plays a significant role with regard to exposure of POPs in top predators. However, it also suggests that the mechanisms of uptake are different for different predators and that the processes are complex. Although there are some indications of a transport signal in the variation of POP concentrations, indirect effects through changes in feeding condition and bird physiology is probably of greater importance. There is a great need for more long-term data on the relationships between a changing climate in the Arctic and the buildup of POPs in the top predators.

5. References [1] Noyes PD, McElwee MK, Miller HD, Clark BW, Van Tiem LA, Walcott KC, Erwin KN, Levin ED. 2009. The toxicology of climate change: Environmental contaminants in a warming world. Environ Int, 35: 971–986 [2] Bustnes JO, Gabrielsen GW, Verreaul, J. 2010. Climate variability and temporal trends of persistent organic pollutants in the Arctic: a study of glaucous gulls. Environ Sci Technol 44: 3155-3161. [3] Bustnes JO, Yoccoz NG, Herzk, D, Ahrens L, Bangjord G, Skaare JU. 2011. Impacts of climate and feeding condition on the accumulation of organic pollutants in a terrestrial raptor. Environ Sci Technol 45:7542-7547. [4] Hebert CE, Hobson KA, Shutt JL. 2000 Changes in food web structure affect rate of PCB decline in herring gull (Larus argentatus) eggs. Environ Sci Technol 34, 1609-1614.

Acknowledgement - The author thank Geir W. Gabrielsen, Børge Moe, Sveinn Are Hanssen, Nigel Yoccoz, Dorte Herzke, and several other scientist for great input in these studies. Validation and first deployment of the DGT technique in artificial human gastrointestinal fluids after ingestion of metal- containing soil particles

Aurélie Pelfrêne1,2, Christophe Waterlot1,2 and Francis Douay1,2

1Université Lille Nord de France, Lille, France 2Groupe ISA, Equipe Sols et Environnement, Laboratoire Génie Civil et géo-Environnement Lille Nord de France (LGCgE), EA 4515, 48 boulevard Vauban, 59046 Lille Cedex, France E-mail contact: [email protected]

1. Introduction The accumulation of metals in soils due to human activities constitutes a potential health risk if directly ingested, especially by children via hand-to-mouth behaviour [1]. Contaminants can be partially or totally released from soil by ingestion, depending on their speciation under gastrointestinal conditions [2]. In vitro tests provide estimates of bioaccessibility, defined as the proportion of contaminant that is dissolved in the artificial gastrointestinal fluids and is potentially available for absorption [2]. The flux toward the intestinal membrane corresponds to both the free metal ion and labile metal species. In contrast, inert species cannot dissociate and thus do not contribute to transport across the intestinal membrane [3]. Estimation of the labile fraction can be assessed with the Diffusive Gradient in Thin films (DGT) technique [4]. Whereas the effectiveness of DGT has been demonstrated for various metals (Cd, Zn, Cu, Ni, Pb) in different exposure media (natural waters, soils and sediments) [4,5], no data is available in artificial human gastrointestinal fluids. The objectives of this study were firstly to validate the performance of the DGT technique for Cd, Pb and Zn in controlled digestive solutions for different time of exposure and different metal concentrations, and secondly to use the technique in the gastrointestinal solutions obtained after carrying out the in vitro Unified Bioaccessibility Method (UBM) developed by the Bioaccessibility Research group of Europe (BARGE) on highly contaminated soils.

2. Materials and methods The experiments were conducted in two validation phases: (a) The simulated gastrointestinal juice was prepared and spiked with a mixture of Cd, Pb, and Zn to a concentration gradient (Figure 1A). For each mixture (0.05-5-1 mg L−1; 0.1-10-2 mg L−1; 0.5-20-5 mg L−1; 1.0- 30-10 mg L−1 for Cd-Pb-Zn, respectively), DGT (open-pore diffusive gel disks + Chelex-100 binding resins from DGT Research, Lancaster, UK) were deployed in 500 mL polypropylene beakers (stirred at 25°C) for 3, 6, 24 and 30 h.

Figure 1: Procedure of DGT device exposure to gastrointestinal fluids. A- Digestive juice spiked with metals. B- Procedure of an artificial digestion and exposure of DGT devices to chyme (modified from Pelfrêne et al. [6]). (b) The UBM test was carried out on highly contaminated soil samples and DGT systems (open-pore gels) were deployed in the resulting chyme for 3 and 6 h (stirred at 25°C and then at 37°C) (Figure 1B). At each studied time, aliquots of solutions were collected and filtered (0.22 µm), and resin gels were retrieved from DGT and eluted for 12 h in 5 mL 1 M HNO3 for metal analyses. Metals were measured in aliquots (i.e. bioaccessible fraction), filtered aliquots and eluates by flame atomic absorption spectrometry (FAAS). 3. Results and discussion

3.1. Validity of DGT measurement for metals in artificial human gastrointestinal fluids The DGT measurements of Cd, Pb, and Zn in gastrointestinal fluids spiked with a mixture of these metals (at 25°C) and those obtained after carrying out the UBM test on one soil sample (at 25°C and 37°C) were validated for the concentration range tested. For each concentration, the accumulated mass of metal on DGT resins was linear as a function of the exposure time as expected by the theory of diffusion, at least as long as the capacity of the resin is not exceeded. Compared to the total dissolved metal concentrations, Cd complexes in the spiked gastrointestinal fluids were mostly DGT-labile (72%), whereas Pb complexes appeared mostly DGT-inert (7.3%); the case of Zn complexes was intermediate (43%) (Figure 2). The introduction of contaminated soil provided evidence for: (i) a substantial increase of metals as particles, but (ii) few changes in the percentage of labile species (63%, 15%, and 33% for Cd, Pb, and Zn, respectively). Moreover, the results provided evidence for a substantial effect of temperature on the diffusion of ions in the gel and on DGT concentrations (Figure 2).

Figure 2: Mean distribution of total Cd, Pb, and Zn between the particulate, dissolved and labile fractions in spiked gastrointestinal fluids and after carrying out the UBM test on one soil sample (at 25°C and 37°C).

3.2. DGT as a speciation tool in digestive juices The DGT devices were deployed in the gastrointestinal fluids after the UBM test was carried out on six soil samples. The results showed: (i) significant variations between particulate and dissolved fractions for Cd and Zn, whereas Pb was mainly present as particles; (ii) the dissolved fraction was composed of 10-87%, 6-46%, and 1-15% of labile Cd, Pb, and Zn species, respectively; and (iii) the gastrointestinal absorption of ingested metals, simulated using DGT, ranged from 8 to 30% for Cd, 0.6 to 11% for Pb, and 0.8 to 7% for Zn.

4. Conclusions

Combining the in vitro test with the DGT technique provided an approach to the labile metal species available for transport across the intestinal epithelium. In this original approach, the DGT technique was found to be simple and reliable in the investigation of metal chemical speciation in digestice fluids and requires further investigation.

5. References [1] Duggan MJ, Inskip MJ, Rundle SA, Moorcroft JS. 1985. Lead in playground dust and on hands of schoolchildren. Sci Total Environ 44:65-79. [2] Oomen AG, Hack A, Minekus M, Zeijdner E, Schoeters G, Verstraete W, Wiele TVD, Wragg J, Rompelberg CJM, Sips AJAM, Wijnen JHV. 2002. Comparison of five in vitro digestion models to study the bioaccessibility of soil contaminants. Environ Sci Technol 36:3326-3334. [3] Van Leeuwen HP. 1999. Metal speciation dynamics and bioavailability: inert and labile complexes. Environ Sci Technol 33:3743-3748. [4] Davison W, Zhang H. 1994. In situ speciation measurements of trace components in natural waters using thin-films gels. Nature 367:546-548. [5] Zhang H, Davison W, Knight B, McGrath S. 1998. In situ measurements of solution concentrations and fluxes of trace metals in soils using DGT. Environ Sci Technol 32:704-710. [6] Pelfrêne A, Waterlot C, Douay F. 2011. Investigation of DGT as a metal speciation tool in artificial human gastrointestinal fluids. Anal Chim Acta 699:177-186.

Acknowledgement - The authors wish to thank the Nord-Pas de Calais Council and ADEME for the financial support of this research Using radioactive and stable metal isotopes to study metal and metalloid availability and ecotoxicity in soils

Mike J McLaughlin1,2 and Jason Kirby1

1CSIRO Land and Water, PMB 2, Glen Osmond, SA 5064, Australia 2Soil Science, School of Agriculture Food and Wine, The University of Adelaide, PMB 1, Glen Osmond, SA 5064, Australia E-mail contact: [email protected]

1. Introduction Methods to study the speciation of metals in the environment has progressed rapidly over the last few decades, with the principal advances being in aqueous phase methodologies. In soils (and sediments), speciation of metals in the solid phase is problematic, with classical sequential fractionation schemes [1] being operationally defined and having several drawbacks [2]. Synchrotron x-ray spectroscopy has opened up new avenues to examine solid phase speciation of metals in soils, but suffers from the drawback that it cannot quantitate metal availability and behaviour, which must be inferred from knowledge of solid-phase forms identified. Isotopic methods can be used to either trace metal/metalloids in particular forms added to soils, or isotopic dilution can be used to examine the fate and behaviour of materials that cannot easily be isotopically labelled (e.g. manufactured materials or wastes). A range of radio- and stable isotopes are available for use in tracing and dilution experiments with metals/metalloids and the most commonly used ones in ecotoxicology are shown in Table 1.

Isotope Half life (blank if stable) 10B 54Mn 312 days 57Co 271 days 63Ni 100 years 64Cu 12.7 hours 65Cu 65Zn 244 days 68Zn 73As 80.3 days 75Se 119.8 days 97Mo 99Mo 66 hours 109Cd 464 days 110mAg 250 days 208Pb Table 1: Commonly used isotopes in soil ecotoxicology Radioisotopes present considerable advantages over stable isotopes in that they are generally cheaper to purchase, and analytical costs are minimal. Stable isotopes require careful sample preparation prior to mass spectroscopic determination, and mass interferences need to be considered during analysis, but they have the advantage of no decay and minimal safety considerations.

2. Isotopic tracing Isotopic tracing requires that the metal/metalloid material be uniformly labelled with the isotope in question. This is realtively easy if soluble metal/metalloid is to be traced, but may not be possible for some complex solid-phase substances e.g. slags, industrial wastes, sewage biosolids. Neutron irradiation can sometimes be used to label complex substances with radioisotopes, but the resultant specific activity of the metals is often too low to prove useful in long-term fate experiments. Short half-lives of some radioisotopes also make them unsuitable for tracing experiments e.g. 64Cu (half life of 12.7 hours) and isotopic dilution is then prefereable to study longer-term reactions, or use of a stable isootpe should be considered (e.g. 65Cu). Tracing experiments can include measurement of partition coefficients (Kd values) in soils, or examination of uptake and/or depuration of metals/metalloids by soils organisms.

3. Isotopic dilution Isotopic dilution is commonly used where tracing of the metal/mealloid form is not possible e.g. for complex industrial matrices such as sewage biosolids, industrial wastes and slags, biological materials such as green wastes. The principal of the technique has been described in detail in the literature [3, 4]. Isotopic dilution has been widely used to examine longer term reactions of metals and metalloids in soils, but care is needed in use of the method as several interferences can be problematic with soil extracts [5] or with redox-sensitive elements [6,7].

4. Application of isotopic methods in soil ecotoxicology

Isotopic methods have been used to quantify the long-term aging of metals/metalloids in soils which can markedly affect their availability and ecotoxicity [8], as well as defining the lability of metals/metalloids in complex wastes after addition to soils [9]. The pool of metal in soils accessed by soil organisms can be identified using isotopes [10] as can the uptake and depuration rates of metasl/metalloids by soil organisms [11]. Isotopic methods provide an extremely valuable tool to probe the fate, behaviour and biological availability of metals and metalloids in soils. The information provided by isotopic methods has already been used in regulatory frameworks for metals risk assessment [12] and will continue to be a vital tool in probing metal and metalloid behaviour in soils. Looking to the future, new methods examining the differences in natural abundance of metal/metalloid isotope abundance will open up our understanding of metal/metalloid availability in soils [13].

5. References [1] Tessier A, Campbell PGC, Bisson M. 1979. Sequential extraction procedure for the speciation of trace metals. Anal Chem 51:844-851. [2] Nirel PMV, Morel FMM. 1990. Pitfalls of sequential extractions. Water Res 24:1055-1056. [3] Hamon RE, Bertrand I, McLaughlin MJ. 2002. Use and abuse of isotopic exchange data in soil chemistry. Aust J Soil Res 40:1371-1381. [4] Young SD, Zhang H, Tye AM, Maxted A, Thums C, Thornton I. 2006. Characterizing the availability of metals in contaminated soils. I. The solid phase: sequential extraction and isotopic dilution. Soil Use Mangement 21:450-458. [5] Ma YB, Lombi E, Nolan AL, McLaughlin MJ. 2006. Determination of labile Cu in soils and isotopic exchangeability of colloidal Cu complexes. Europ J Soil Res 57:147-153. [6] Hamon RE, Lombi E, Fortunati P, Nolan AL, McLaughlin MJ. 2004. Coupling speciation and isotope dilution techniques to study arsenic mobilization in the environment. Environ Sci Technol 38:1794-1798. [7] Wendling LA, Kirby JK, McLaughlin MJ. 2008. A novel technique to determine cobalt exchangeability in soils using isotope dilution. Environ Sci Technol 42:140-146. [8] Ma YB, Lombi E, Oliver IW, Nolan AL, McLaughlin MJ. 2006. Long-term aging of copper added to soils. Environ Sci Technol 40:6310-6317. [9] Lombi E, Hamon RE, Wieshammer G, McLaughlin MJ, McGrath SP. 2004. Assessment of the use of industrial by-products to remediate a copper- and arsenic-contaminated soil. J Environ Qual 33:902-910. [10] Scott-Fordsmand JJ, Stevens D, McLaughlin M. 2004. Do earthworms mobilize fixed zinc from ingested soil? Environ Sci Technol 38:3036-3039. [11] Sheppard SC, Evenden WG, Cornwell TC. 1997. Depuration and uptake kinetics of I, Cs, Mn, Zn and Cd by the earthworm (Lumbricus terrestris) in radiotracer-spiked litter. Environ Toxicol Chem 16:2106- 2112. [12] Smolders E, Oorts K, Van Sprang P, Schoeters I, Janssen CJ, McGrath SP, McLaughlin MJ. 2009. Toxicity of trace metals in soil as affected by soil type and aging after contamination: Using calibrated bioavailability models to set ecological soil standards. Environ Toxicol Chem 28:1633-1642. [13] Weiss DJ, Rehkämper M, Schoenberg R, McLaughlin M, Kirby J, Campbell PGC, Arnold T, Chapman T, Peel K, Gioia S. 2008. Application of non-traditional stable isotope systems to the study of sources and fate of metals in the environment. Environ Sci Technol 42:655-664.

Acknowledgement - The authors thank the industries of the Metals Environmental Research Association for supporting much of the research developing isotopic methods to study metal availability in soils. Weathering of silver nanoparticles could increase their bioavailability

Claire Coutris1, Turid hertel-Aas1, Emmanuel Lapied1,2, Erik J. Joner2, and Deborah H. Oughton1

1Norwegian University of Life Sciences, P.O.Box 5003, N-1432 Ås, Norway 2Bioforsk Soil and Environment, Fredrik Dahls vei 20 , N-1432 Ås, Norway E-mail contact: [email protected]

1. Introduction The major challenge in tracing engineered nanoparticles (ENPs) in complex media, such as soils, is to detect their presence, transfer to organisms and their interactions with the surrounding environment. One possibility to overcome this issue is to use neutron activation where ENPs are subjected to a strong neutron flux that induces a more or less transient radioactive property in the ENPs without changing other chemical or physical properties that influence their behaviour during experimentation. Radioactive ENPs are subsequently detected and quantified by counting of gamma rays emitted by the isotopes that are formed. To date, an important amount of toxicity data on ENPs is available, but data on exposure are still needed to be able to conduct risk assessment. In a first experiment, we followed the uptake and excretion of Ag from either AgNPs or AgNO3 in the earthworm Eisenia fetida. In a second experiment, we studied the partitioning of Ag from either AgNPs or AgNO3 in two natural soils of contrasting organic matter content, and over time.

2. Materials and methods Silver nanoparticles (AgNPs 20 nm, Quantum Sphere, USA) were characterized with regards to particle size and shape, crystallographic struture, specific surface area and zeta potential; and submitted to neutron activation.

In a first experiment, earthworms Eisenia fetida were exposed via their food to either AgNPs or AgNO3 for 28 days and let for depuration in clean soil for 2 months. Living earthworms were analysed regularly during the uptake and excretion period by gamma spectrometry to determine the evolution of their silver content. In a second experiment, the same AgNPs were added to two natural soil of contrasting organic matter content and left to age for 2 h, 2 days, 5 weeks and 10 weeks before they were submitted to sequential extraction and analysed by gamma spectrometry for silver content.

3. Results and discussion

3.1. Bioavailability to the earthworm Eisenia fetida At the end of the exposure period (day 28), earthworms had body concentrations corresponding to 5.1 ± 0.5 % and 11.0 ± 0.3 % of the concentration in the food for AgNPs and Ag ions, respectively. These values decreased by 80 % and 93 % within 48h depuration in clean soil, for AgNO3 and Ag NPs, respectively. After two months depuration, 97 % and 99 % of the accumulated Ag from Ag ions and AgNPs, respectively, were excreted (Fig.1). 0.12

0.10 AgNPs

0.08 Ag ions

0.06

0.04 Bioaccumulation Factor Bioaccumulation 0.02

0.00 0 14 28 42 56 70 84 98 Days -1 -1 Figure 1: Bioaccumulation factors (µg Ag g ww worm/µg Ag g ww food) for AgNPs and AgNO3 in the earthworm Eisenia fetida exposed for 28 days to either AgNPs or AgNO3 and subsequently let for depuration in clean soil for two months.

3.2. Influence of aging and organic matter content on silver bioaccessibility Bioaccessible Ag was defined as the sum of Ag extracted by water and ammonium acetate. A rapid reduction of Ag ions occured when they get in contact with soil organic matter, turning Ag ions into NPs and colloids. Soil properties had a limited impact on Ag speciation. Interestingly, the bioaccessible fraction increased over time in case of AgNPs, contrary to what happened with AgNO3 (Fig.2).

50 a AgNO3 Organic

AgNPs Organic 40 AgNO3 Mineral b

30 AgNPs Mineral %

20

c 10 b a b a b a b b d a c b 0 c 0 10 20 30 40 50 60 70 Days 110m Figure 2: Bioaccessible Ag in organic and mineral soils spiked with either radiolabeled AgNO3 or AgNPs, over time. Results are mean ± SD (n=4). Different letters indicate significant changes along time within a treatment. For each time point, boxes group points that are not significantly different.

4. Conclusions

We showed that the studied AgNPs were more bioaccessible than Ag ions over time, since they could act as a constant source of relatively stable and bioaccessible Ag. This increase in bioaccessible Ag in soil spiked with AgNPs, being between 8-9 times greater than the bioaccessible fraction of AgNO3 after 70 days contact time, calls for caution in ENP risk assessment, and the low bioavailability of AgNPs to earthworms should be re-evaluated in light of the increase of silver bioaccessibility as particles weather in soil.

Acknowledgement - The authors acknowledge financial support from the Research Council of Norway. Evaluating the impact of soil ageing on the toxicity of Ag nanoparticles to Eisenia fetida

Steven M. Lev1, Michael Doody1, David R. Ownby1 and Ryan E. Casey1

1Urban Environmental Biogeochemistry Laboratory, Towso University, Towson, MD, USA E-mail contact: [email protected]

1. Introduction

The increased production and use of engineered nanoparticles in a variety applications increases the potential for exposure to these particles in the environment [1]. Currently, very little is known about how metal nanoparticles behave once released into the environment and even less is know about the effect of these particles on terrestrial organisms. The purpose of this investigation was to characterize the difference in toxicity and the impact of ageing between silver nanoparticles and silver nitrate in OECD soil on the earthworm Eisenia fetida. The potential to modify the toxicity of a silver nanoparticle contaminated soil over time is an important temporal consideration when conducting a terrestrial risk assessment.

2. Materials and methods

Soil media was prepared according to OECD protocols: 70% quartz sand, 20% kaolinite clay, 10% dried Sphagnum peat moss , and adjusted to pH 7.15 with CaCO3. Soil treatments were prepared with dissolved AgNO3 or suspensions of 30-50 nm Ag nanoparticles (NP) at nominal concentrations of 0, 25, 50, 100, 200, 300, 400, 500, 600, 800, 1000, 1250, 1500, and 2000 mg Ag/kg soil. Soils treatements were then split and one batch was allowed to age for 28 days in an incubator and kept at constant moisture. A set of Earthworms were exposed to the AgNO3 and AgNP spiked soils 24 hours after initial preparation and then a second set of earthworms were exposed to the soils aged 28 days. Both exposures lasted 14 days with endpoints of mortality and body burden. The aged soils were sampled every 7 days and subjected to a sequential extraction procedure to evaluate changes in Ag speciation. All soil and tissue samples were analyzed by ICP-MS

3. Results and discussion

Results from the first exposure showed high mortality for worms exposed to silver nitrate and almost no mortality for those individuals exposed to Ag nanoparticles (Figure 1, left). The exposure to soils aged 28 days showed a decrease in mortality in individuals exposed to the AgNO3 treatments and an increase in mortality in those exposed to the aged AgNP soils (Figure 1, right)

Figure 1. Plot of survival in all exposures for both the initial AgNP and AgNO3 treatments and the AgNP and AgNO3 soils aged 28 days prior to exposure. The Ag body burden for both AgNP exposures were indistinguishable while there was a decrease in the Ag body burden for earthworms in the AgNO3 exposures aged 28 days as compared to freshly amended soils. There were changes is the speciation of Ag over the 28 day ageing period in both soil treatments that point toward an increase in the potentially bioavailable pool of metal in AgNP amended soils as compared to the AgNO3 amended soils.

3. Conclusions

There is an increase in toxicity of AgNP aged soils to Eisenia fetida as compared to freshly amended soils. In all exposures, AgNO3 treatments were more toxic than the AgNP treatments. There is an increase in the size of the potentially bioavailable Ag pool after 28 days in the AgNP amended soils. This larger pool however, did not result in an increased Ag body burden. Based on these results, the potential exists that morphological changes to the AgNPs in the soil matrix occurred during ageing and that these changes in conjunction with more bioavailable Ag made these treatments more toxic to exposed individuals.

4. References [1] Scheringer M. Nat. Nanotechnol 2008; 3(6):322-323.

Acknowledgement - The authors thank the University of Maryland System, W.H. Elkins Endowment for funding to suppor this project. Environmental Monitoring Networks are Important Tools to Assess Chemical Regulations

Amina Salamova, Marta Venier, and Ronald. A. Hites

School of Public and Environmental Affairs, Indiana University, Bloomington, Indiana 47405 USA E-mail contact: [email protected]

1. Introduction A recent expert meeting organized by the RECETOX Centre in Brno, Czech Republic, has identified gaps, challenges, and research needs associated with the global assessment of hazardous chemicals (1). One of the important areas of concern recognized by this workshop was a need in developing a range of techniques addressing an improved assessment of spatial and temporal trends of the chemicals of global concern. The ultimate goal of this proposal was to produce policy-relevant scientific knowledge, providing support to the globally coordinated management of hazardous chemicals. Establishment of carefully designed environmental monitoring networks can be an important tool in the assessment of trends of toxic compounds in the environment and development of policy regulations on production and use of these chemicals, as well as testing the effectiveness of already existing regulations. The goal of this paper is to present an example of a North American environmental monitoring network, emphasizing methodological and technical details, as well as the results of these monitoring efforts. The Integrated Atmospheric Deposition Network (IADN) is a joint monitoring and research program between the United States Environmental Protection Agency and Environment Canada. IADN was begun in 1990 through mandates of the Clean Air Act and the Great Lakes Water Quality Agreement to monitor the atmospheric deposition of persistent organic pollutants into the Great Lakes. IADN operates several master and satellite sampling sites in the basin of the Great Lakes. The sites were strategically located according to a series of sampling criteria to asses both urban and regional sources of contaminants. Both vapor and particle atmospheric phases, as well as precipitation, are sampled. Vapor and particle phase samples are taken every 12 days; and precipitation samples are taken every month at each IADN site. This extensive database provides insights into the spatial and temporal trends of target compounds, their sources, fates, and transport patterns, as well as background concentrations around Great Lakes. IADN flame retardant data for 2005-2009 time period will be presented here as an example of how environmental monitoring data can be used to assess temporal and spatial trends of persistent chemicals.

2. Experimental Section The locations of the United States IADN sampling sites are shown in Figure 1. The two urban sites are in Chicago, Illinois (41.8344 °N, −87.6247 °W) and Cleveland, Ohio (41.4921 °N, −81.6785 °W). A rural site is located at Sturgeon Point, New York (42.6931 °N, −79.0550 °W). The two remote sites are at Sleeping Bear Dunes, Michigan (44.7611 °N, −86.0586 °W) and Eagle Harbor, Michigan (47.4631 °N, −88.1497 °W). The IADN website provides detailed information on air sampling procedures and site operations (www.msc.ec.gc.ca/iadn). The atmospheric samples discussed here were collected during the period of January 1, 2005 to December 31, 2009.

Figure 1. United States Integrated Atmospheric Deposition Network sampling sites. A modified Anderson high-volume air sampler (General Metal Works, model GS2310) was used to collect air samples for 24 hours every 12 days with a flow rate giving a total sample volume of ~820 m3. The gas phase was collected on Amberlite XAD-2 resin (Supelco, Bellefonte, PA; 20-60 mesh) held in a stainless steel cartridge, and particles were collected on Whatman quartz fiber filters (QM-A, 20.3 × 25.4 cm). Precipitation samples were collected using MIC automated wet-only samplers (MIC Co., Thornhill, ON). Each sampler consists of a 46 × 46 cm stainless steel funnel connected to a 30-cm long by 1.5-cm i.d. glass column (ACE Glass, Vineland, NJ) packed with XAD-2 resin. Precipitation events are integrated over each calendar month. Details of the sampling procedures and site operations, as well as summary of sample treatment and chemical analysis procedures can be found elsewhere (2-4). The samples were analyzed for 34 congeners of polybrominated diphenyl ethers (PBDEs, congeners 7, 10, 15, 17, 28, 30, 47, 66, 85, 99, 100, 119, 126, 138-140, 153, 154, 156, 169, 180, 183, 184, 191, 196, 197, 201, and 203-209), and for decabromodiphenylethane (DBDPE), hexabromobenzene (HBB), pentabromoethylbenzene (PBEB), and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) on an Agilent 6890 series gas chromatograph coupled to an Agilent 5973 mass spectrometer using helium as the carrier gas.

3. Conclusions

Overall, Chicago and Cleveland have the highest concentrations of PBDEs, BTBPE, and DBDPE in all three phases, suggesting a strong urban atmospheric source of these pollutants. The two remote sites, Sleeping Bear Dunes and Eagle Harbor, have the lowest concentrations of these contaminants. The remote site at Eagle Harbor had particularly high levels of PBEB in all three phases, and the rural site at Sturgeon Point had the highest HBB concentrations in the vapor phase. To investigate temporal trends of these compounds in the period of 2005-2009, a multiple linear regression was applied to the concentrations of these chemicals in all three phases combined together. PBDE concentrations showed decreasing trends over time, with halving times of ~6 years. The concentrations of HBB and BTBPE are decreasing with halving times of ~10 years. PBEB and DBDPE concentrations did not show any change between 2005 and 2009, suggesting continuing source for these compounds. Overall, the results of IADN, as a monitoring and research effort, indicate that long-term monitoring tools are instrumental in policy-related decision making.

4. References [1] Klánová, J.; Diamond, M.; Jones, K. et. al. Identifying the research and infrastructure needs for the global assessment of hazardous chemicals ten years after establishing the Stockholm Convention. Environ. Sci. Technol. 2011, 45, 7617-7619. [2] Basu, I.; Bays, J. C. Collection of air and precipitation samples: IADN project standard operating procedure. Indiana University, Bloomington, IN. 2005; http://www.indiana.edu/~hiteslab/FieldSOP2005.pdf. Accessed 21 June 2011. [3] Carlson, D. L.; Basu, I.; Hites, R. A. Annual variation of pesticide concentrations in Great Lakes precipitation. Environ. Sci. Technol. 2004, 38, 5290-5296. [4] Basu, I. 1999. Analysis of PCBs, pesticides, and PAHs in air and precipitation samples, IADN project Sample Preparation Procedure; Indiana University, Bloomington, IN. http://www.msc-smc.ec.gc.ca/iadn/resources/resources_e.html. Accessed 21 June 2011.

Acknowledgement - The authors thank the U.S. Environmental Protection Agency’s Great Lakes National Program Office for funding (GL995656, Todd Nettesheim, project officer), Ilora Basu, and Team IADN for the operation of the network. Assessment of Persistent Organic Pollutant in the atmosphere of Latin America

Karina S. B. Miglioranza1,2, Mariana Gonzalez1,2, Paola M. Ondarza1,2, Francesca Mitton1,2, Ricardo Barra3, Gilberto Fillmann4.

1 Laboratorio de Ecotoxicología, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Mar del Plata, Argentina. 2 Instituto de Investigaciones Marinas y Costeras (IIMyC) CONICET, Argentina 3 EULA-Chile Centro de Ciencia Ambientales, Universidad de Concepción, Concepción, Chile 4Laboratório de Microcontaminantes Orgânicos e Ecotoxicologia Aquática, Universidade Federal do Rio Grande, Rio Grande, RS, Brazil. E-mail contact: [email protected]

1. Introduction The widespread use and distribution of pesticides, industrial and urban chemicals and the consequent release into the environment, is of great worldwide relevance [1]. Atmospheric transport is responsible for pollutant dispersal over long distances. As part of an atmospheric regional network, a monitoring program involving the use of pine needles, epiphytes and passive samplers is conducted. Pine needles (Pinus sp.) can accumulate hydrophobic compounds such as organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyls ethers (PBDEs) from air. Moreover, they integrate contaminants loads over a long time. All these compounds, included in the Stockholm Convention, are of concern due to their distribution, global transport and toxicity [2, 3]. Pine needles were used to evaluate latitudinal and longitudinal transport of contaminants in central and Patagonian regions from Argentina, with a 20 stations network. The epiphyte Tillandsia bergerii was used to evaluate local sources at small scale. Passive samplers (XAD-2) constitute the aim of our Latin American Atmospheric Passive Sampling Network (LAPAN) where 46 sites are actually covered while 80 sites are at least our endeavor to reach.

2. Materials and Methods The network involves regions of Antarctica and 12 countries including urban, agricultural and industrial areas. Pine needles samples were 1 year old. The sampling height was 2.5–3 m. Epiphytes were sampled and transplanting to urban, periurban and rural areas. OCPs, PCBs and PBDEs were extracted according to Metcalfe and Metcalfe,1997 [4], with modifications of Miglioranza et al. 2003 [5]. Analyses are performed by GC-ECD and GC-MS. All data are expressed in ng/lipid weight. Passive samplers were hold in different sites and left 1 year until sampling. Resins XAD-2 [6] were treated as other samples following the same methodology.

3. Results and Discussion Pine needles analyses revealed that among OCPs, the currently used endosulfans, are the main pesticides found, particularly associated with agricultural areas, however DDE, the DDT metabolite, is also found in all sites independently of particular sources, as a consequence of their intensive past use in the region. Regarding PCBs, a predominance of #110, 118, 153, 138 is found, related with punctual sources. Considering the latitudinal gradient, until the southeast region of Argentina, an increasing in DDT, PCBs and PBDEs (BDE-28 and 47) is observed inferring an atmospheric transport of these compounds. PBDEs and PCBs levels in T. bergerii showed a concentric distribution around the urban settlement with a clear hot spot near a waste disposition site, that is accomplished by the presence of PBDEs 28, 47, 99 and 100 and PCBs 153, 138, 110 and 118.

Pine needles: Pinus sp. Epyphites: Tillandsia bergeri

2 1 3 5 4 6 7

PAS (LAPAN) Endosulfan sulfate > β > α-isomer Metabolism of α− isomer Waste dumping site is a (70 % of technical mixture) HOT SPOT for PCBs and PBDEs to endosulfan sulfate PAS (XAD-2)

4. Conclusions Endosulfans and DDTs were the main pesticides found. Particularly Endosulfan levels denote the current use in the region with the presence of α- and β- isomers and the predoiminance of the metabolite endiosuflan sulfate, enhanced this distribution by the proximity to agricultural areas. In all industrial or urban sites the relation PBDEs/PCBs >1 reflect the general trend of diminishing PCBs levels and increasing the emergent PBDEs. The southeast region of Argentina denotes enrichment in OCPs, PCBs and PBDEs levels. Since point sources are not evident, atmospheric transport as the main mechanism involved is suggested.

5. References [1] Pozo K., Harner T., Wania F., Muir D., Jones K.C., Barrie L.A. 2006. Environ. Sci. Technol .40, 4867-4873. [2] Mackay D, Wania F, 1995. Science of the Total Environment 160/161, 211-232. [3] Czub G, Wania F, McLachlan MS 2008. Environ Sci Technol 42, 3704–3709. [4] Metcalfe T L, Metcalfe CD 1997. Sci Total Environ 201:245-272. [5] Miglioranza K, Aizpun J, Moreno V 2003. Environ Toxicol Chem 22:712-717. [6] Hayward SJ, Lei YD, Wania F 2011. Atmos Environ, 45, 296-302.

Aknowledgement: This work was supported by PICT 07-410, Agencia Nacional de Promoción Científica y Tecnológica (ANPCyT) from Argentina. G. Fillmann (PQ 311459/2006-4 and 314335/2009-9) was sponsored by CNPq (Brazilian National Research Council).

Occurrence of Currently Use Pesticides and Selected Degradation Products in Agricultural Regions of Western Canada

Renata Raina1, Lin Sun1, Patricia Hall1, Erika Smith1, Nicole Fergus1

1University of Regina, 3737 Wascana Parkway, Regina, SK, S4S 0A2 E-mail contact: [email protected]

1. Introduction Initial studies on occurrence of currently used pestides in agricultural regions of Western Canada focused on the Lower Fraser Valley where berries and fruits are the dominant crops, and the Canadian prairies where grains and oil seed crops dominate. These two agricultural regions were selected due to their differences in crop types, climate, and expected usage of pesticides. Western Canadian agricultural regions have the highest historical usage of pesticides in Canada. In the initial studies we focused on key pesticides that we suspected to be of concern sampling occurred prior to the availablility of the 2003 usage inventory. These pesticides had little information about their atmospheric occurrence in Canada. In the Lower Fraser Valley (LFV) we examined trihalomethyl thiofungicides and were able to detect captan and folpet, while in the prairies triallate, trifluralin, and ethalfluralin were determinined to be key herbicides that were still dominant in the atmosphere. From these studies the gas/particle partitioning of captan and folpet was also examined. In addition we also examined the differences between the two distinct agricultural regions, and provided the first detection in the atmosphere and seasonal trends of organophosporus oxon degradation products along with thier active OP ingredient in North America. Ratio of degradation product/active ingredient were also used to identify the age of the source and to provide insight into future studies on the relative importance of local, regional, and long-range atmospheric transport sources. In the next phase of the research started in 2011 we expanded the number of sampling locations in each of these agricultural regions starting in the LFV and an adjacent agricultural region, Okanagan Valley, which is more heavily dominated by orchards and vineyards. A summary of the currently used pesticides that are part of this 5-year study and some preliminary results will be presented.

2. Materials and methods GC or LC/MS/MS analysis is used for the analysis of currently used pesticides as previously described [1-4]. Air sampling takes place from 1-7 day durations at selected sites in the LFV (Abbotsford, BC; Chilliwack, Clearbrook), Okanagan Valley (Summerland, Osoyoos, Osoyoos-Oliver); and the Canadian Prairies (Bratt’s Lake, SK) in selected time periods between 2003-2011. PUF high-volume air sampler (Tisch Environmental, Cleves, OH, USA), with typical air flow rates of 225 L/min was used with shorter sample durations selected during more intensive growing or application times when usage was suspected to be higher. In 2011 the PUF air samplers were also equipped with a PM2.5 cyclone for determination of pesticides on fine particles, and a comparison of the standard PUF sampler with a co-located PUF sampler with PM2.5 inlet was made at Bratt’s Lake, SK.

3. Results and discussion

3.1. Trihalomethylthio Fungicides in the LFV These pesticides had little information about their atmospheric occurrence. In the Lower Fraser Valley (LFV) we examined trihalomethyl thiofungicides and were able to detect captan and folpet. Due to the lower vapour pressure of captan, it was found in both the particle and gas phase, while folpet was only detected in the gas phase [1]. Seasonal atmospheric concentrations in the LFV were dominanted by the particle phase concentrations of captan and showed the importance of examining atmospheric transport processes on particles.

Range pg/m3 Captan (Total) Captan (Particle Phase) Folpet (Total) (Time Period)* May-Dec 2004 54.9-3134 Not available 22.1-1723 Jan-Dec 2005 30.0-9287 30-8617 35.4-1064 Jan-Dec 2006 99.1-13205 99.1-10973 86.3-923 Table 1: Captan and Folpet Concentrations in the LFV, *range for samples > MDL

3.2. Azole Fungicides in the Canadian Prairies In the prairies we also provided the first detection of azole fungicides in the atmosphere in the gas phase and related these to precipitation during a wetter than normal year (2010).[2]

Time Period Propiconazole Prothioconazole- Hexaconazole desthio Apr-Oct, 2010 Range pg/m3 0.59-77.9 2.2-37.5 0.5-1.5 (% above MDL) (50%) (32) (5%) MDL* 0.16 1.2 0.4 Table 2: Concentrations of Azole fungicides in the Gas Phase at Bratt’s Lake, SK, *MDL based on weekly sample duration

3.3. OPs and OP Oxons during 2005 There were significant differences in the two agricutural regions in the individual OPs (see Table 3) that were detected along with their OP oxon. Seasonal variations were also related to expected usage patterns for different crop types.[3,4] Time Period Diazinon at Malathion at Chlorpyrifos at Malathion at Abbotsford, BC Abbotsford, BC Bratt’s Lake, SK Bratt’s Lake, SK

(pg/m3) (pg/m3) (pg/m3) (pg/m3) 2005 4.0-25000 0.6-12900 0.6-1380 0.7-69.9 2003 2.2-233286 Table 3: Concentrations of OPs at Abbotsford, BC in LFV and Bratt’s Lake, SK in the Canadian Prairies

4. Conclusions

The occurence in the atmosphere of a number of chemical classes of currently used pesticides has been observed in the Canadian prairies and the LFV, and more recently in the Okanagan Valley. Some key chemical classes of pesticides that have been detected in the atmosphere in either the gas or particle phase include organophosphorus pesticides, their more toxic degradation products (OP oxons), pre-emergent herbicides, trihalomethyl thiofungicides, and more recently azoles and carbamates.

5. References [1] Raina, R. Smith E. Accepted 2011. Detection of azole fungicides in atmospheric samples collected in the Canadian praires. J AOAC Int. Special Section on Pesticide Residue Analysis. [2] Raina R, Belzer, W, Jones K. 2009. Atmosphere Concentrations of captan and folpet in the Lower Fraser Valley agricultural region of Canada, J Air, Soil, Water Research 2: 41-49. [3] Raina R, Hall P, Sun L. 2010.Occurrence and Relationship of OP Insecticides and their Degradation Products in the Atmosphere in Western Canada. Envir Sci Technol 44:8541-8546. [4] Raina, Chapter 5, in Pesticides Strategies for Pesticide Analysis, edited by M. Stoytcheva, www.intechopen.com, INTECH, ISBN 978-953-307-460-3, Jan 2011.

Acknowledgement - The authors thank Environment Canada, BC Ministry of Environment, Metro Vancouver, Agriculture and Agri-Food Canada for the use of sampling sites and staff support for sampling. Semi-volatile organic pollutants and trace metals associated with Saharan dust air masses: Estimated inhalation exposures at source and downwind sites

Virginia Garrison1, Suzette Morman2, William Foreman2, Susan Genualdi3,4, Michael Majewski5, Azad Mohammed6, Geoffrey Plumlee2, Stacy Massey Simonich3

11U.S. Geological Survey, 600 4th Street South, St. Petersburg, FL 33701, U.S.A. 2U.S. Geological Survey, PO Box 25582, Denver, CO 80225, U.S.A. 3Department of Chemistry, Oregon State University, Corvallis, OR 97331-7301, U.S.A. 4Food and Drug Administration, College Park, MD U.S.A. 5U.S. Geological Survey, 6000 J Street, Sacramento, CA 95819, U.S.A. 6Faculty of Science, University of the West Indies, St. Augustine, Trinidad and Tobago E-mail contact: [email protected]

1. Introduction The Saharan Air Layer (SAL) transports eroded mineral dust, chemical contaminants, and microorganisms thousands of kilometers through the atmosphere from the Sahara/Sahel of Africa to the Americas, Europe and Asia [e.g.,1]. The quantities and composition of dust and contaminants lifted into the atmosphere and advected via the SAL are the result of ocean-atmosphere interactions, regional meteorology, surface material composition, and human activities in the dust source region. Semi-volatile organic compounds (SOCs) such as banned and current use pesticides, polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) have been detected during Saharan dust events in source (Mali) and downwind locations to the west (Cape Verde, Trinidad and Tobago, and U.S. Virgin Islands) [2,3]. All are known to persist in the environment, bioaccumulate and be hazardous or toxic to humans and other organisms. Some banned pesticides such as DDT are currently used in the source region against agricultural pests (locust plagues) and disease vectors (e.g., malarial mosquitos) [2]. Primary sources of PAHs in Mali include small, garbage-and-biomass-burning low temperature fires and vehicle exhaust (primarily diesel and two-stroke gasoline engines) [2]. Concentration data from source and downwind sites during Saharan dust events were used to estimate inhalation exposure (mass of pollutants that could be inhaled into the lungs in one day) to detected: total and individual pesticides; total PAHs; total PCBs; and potentially hazardous or biologically active (e.g., Fe) trace metals. Because biological exposure to metal(loid)s is dependent on species mobility in the body, preliminary investigations of bioaccessibility of inhaled particle-associated trace metals were conducted using simulated lung fluid [4].

2. Materials and methods Air samples were collected during Saharan dust conditions at sites in the source region [Bamako (in the Niger River valley) and Kati (on an escarpment above Bamako), Mali] and at downwind sites [off the African continent (Cape Verde); in the southeastern Caribbean (Trinidad and Tobago); and in the northeastern Caribbean (St. Croix, U.S. Virgin Islands)][3]. High volume samplers were used to collect: 1) trace metal(loid)s on preconditioned quartz fiber filters; 2) SOCs on preconditioned glass fiber filters (particles) followed by two polyurethane foam plugs (gas phase). Samples were analyzed for 30 elements and 84 targeted SOCs [3]. Sites, sampling methodology, laboratory analysis, and criteria for Saharan dust conditions are detailed in [3]. Bioaccessibility of inhaled particle-associated trace metals was investigated using simulated lung fluid [4]. Inhalation exposure to total and individual pesticides, total PAHs, total PCBs, and biologically active trace metals was estimated using: analyte concentration data for source and downwind sites during Saharan dust events; average lung tidal volume (0.5 l); and, 12 breaths per minute respiration.

3. Results and discussion Estimated inhalation exposures [nanograms per day (ng/d)] were orders of magnitude higher in source than downwind sites (fig. 1). Inhalation exposures ranged from 17-1085 ng/d for total SOCs in the source region and <1-6 ng/d at downwind sites. Similarly, estimated inhalation exposures to metal(loid)s were higher in source than downwind sites. Bioaccessibility in simulated lung fluid was found to vary (0-100%) among trace metals (and redox state) and by source-downwind location. Iron and potentially toxic elements (As, Cr, Cu, Mn) showed enhanced bioaccessibility in downwind (Caribbean) samples from Saharan dust events. Estimated inhalation exposures to bioaccessible metal species ranged from <1-2519 ng/d Fe, and < 1-11 ng/d As in the source region and 55-2006 ng/d Fe and <1-4 ng/d As in Caribbean sites. All Saharan dust event samples contained multiple SOCs and biologically active trace metals, raising the question of possible additive or synergistic effects in humans and other organisms. 1000 5

100

10 14 10 4 1 1/1 7 2 5 1/1 0.1

log (nanograms log per day) 0.01

Kati Bamako Tobago Trinidad Trinidad Cape Verde non-dust Virgin Islandsnon-dust Virgin Islands Trinidad - local Figure 1. Box plot of estimated inhalation exposure to total detected pesticides [log (nanograms per day)] assuming 12 breaths min-1 and tidal volume 0.5 l min-1. Number of samples per site shown above box plots.

4. Conclusions

Humans in the Saharan dust source region may inhale orders of magnitude greater amounts of many hazardous SOCs and trace metal(loid)s from the air than at downwind sites in the Caribbean and off the African coast during African dust events. Unfortunately, the paucity of information on toxicity of inhaled SOCs and some trace metals (individually and in mixtures) limits interpretation of exposure estimates.

Bioaccessibility (0–100%) among trace metals (and redox state) in simulated lung fluid differed between source and downwind locations, with higher bioaccessibility for some metals at downwind locations. This is likely due to chemical and physical processes (e.g., reduction of Fe and gravitational settling) occurring during long-distance transport of the dust particles and associated contaminants that result in changes in metal redox state and finer particle-size fractions. Fe is of particular interest due to its abundance in Saharan dust, greater bioaccessibility at downwind sites, and ability to induce an inflammatory response in the body.

Basic research is needed to: (1) determine inhalation toxicity of the SOCs and biologically active trace metal(loid)s; (2) elucidate bioaccessibility pathways of inhaled metal(loid)s; (3) identify changes to metal(loid)s during atmospheric transport in order to assess bioaccessibility and resulting effects on organisms and ecosystems when deposited, inhaled or ingested; and, (4) establish whether negative biological effects from exposure to SOC and biologically active trace metal mixtures in African dust might be additive or synergistic.

5. References [1] Moulin C, Lambert CE, Dulac F, Dayan U. 1997.Control of atmospheric export of dust from North Africa by the North Atlantic Oscillation. Nature 387: 691–694. [2] Garrison VH, Foreman W., Genualdi S, Griffin DW, Kellogg CA, Majewski MS, Mohammed A, Ramsubhag A, Shinn EA, Simonich SL, Smith GW. 2006. Saharan dust – a carrier of persistent organic pollutants, metals and microbes to the Caribbean? Revista Biologia Tropical 54 (Suppl. 3): 9-21. [3] Garrison VH, Foreman WT, Genuald, SA, Majewsk, MS, Mohammed A, Simonich SM. 2010. Concentrations of semivolatile organic compounds associated with African dust air masses in Mali, Cape Verde, Trinidad and Tobago, and the U.S. Virgin Islands, 2001-2008: U.S. Geological Survey Data Series 571, 1 DVD. [http://pubs.usgs.gov/ds/571]. [4] Plumlee GS, Morman SA, Ziegler TL. 2006. The toxicological geochemistry of earth materials: An overview of processes and the interdisciplinary methods used to understand them. Reviews in Mineralogy & Geochemistry 64: 5-57.

Acknowledgements - The authors thank the U.S. Geological Survey; National Park Service, the van Heckmanns (St. Croix, U.S. Virgin Islands); Institute of Meteorology and Geophysics (Republic of Cape Verde); American International School Bamako, Ministry of Communications (Republic of Mali); Environmental Management Authority, Maritime Services, Tobago House Assembly, and University of the West Indies (Trinidad and Tobago). Re-visiting the Modelling of Soil-Air Partitioning, Fugacities in Soil, and Soil-Air Exchange of Persistent Organic Pollutants

Jordi Dachs1, Ana Cabrerizo1, Damià Barceló1

1Department of Environmental Chemistry, IDAEA-CSIC, Jordi Girona 18-26, Barcelona, Catalunya, Spain E-mail contact: [email protected]

1. Introduction Soils are the main reservoir of persistent organic pollutants in the environment and air-soil exchange of POPs is a key process affecting the atmospheric occurrence of POPs and the extent of soil as a sink of pollutants. The direction of the air-soil exchange can be determined by comparing the POP fugacity in soil (fs) and the fugacity in ambient air (fa). If fs is higher than fa, then there is a net volatilization, while if fs is lower than fa then there is a net deposition. Fugacities in soil and air are often estimated from the POP concentration in soil (Cs) and ambient gas phase concentrations (CG) by, RT f S = CS [1] K SA MW

f G = CG RT [2]

Where R is the gas constant, T is the temperature, KSA is the soil-air partition coefficient and MW is the molecular weight. One of the estimation methods more often used to estimate KSA is given by (Fenizio et al. 1997),

CS ζ Oct MWOct K SA = = f OC K OA [3] CGS ζ OM MWOM dOCT

Where CGC is the gas phase concentration equilibrated with the surface soil, foc is the fraction of organic carbon in soil, MWOct and MWOm are the molecular weight of octanol and soil organic matter respectively; ζoct and ζom are the activity coefficient of the POP in octanol and organic matter, doct is the density of octanol and KOA is the octanol-air partition coefficient. Unfortunately the activity coefficients are largely unknown for POPs and there is also high uncertainty in the soil organic matter MW. Thus, previous models incorporating soil-air exchange need to make assumptions on the value of these parameters. The recent development of a soil fugacity sampler (Cabrerizo et al. 2009) allows to determine under controlled field conditions the value of fs experimentally. This method has been applied to determine fs and the corresponding measurements of KSA in temperate and polar regions with different SOM characteristics and foc ranging from 0.001 to 0.5 (Cabrerizo et al. 2011a,b,c, Cabrerizo et al. 2012). This data set of more than 50 measurements of KSA allows to explore the variables affecing the different parameters appearing in equation [3] and allows determine their values as a function of environmental variables. In addition, the data set also allows to fit and validate other models for soil-air partitioning of POPs such as those using the multi- parametric linear free energy (pp-LFER)relationships which is given by,

log K SA = sS + aA + bB + lL + vV + c [4] Where S, A, B, L and V are the compound specific Abraham descriptors for the polarizability, electon acceptor capability, electron donor capability, logarithm of the hexadecane/air partitioning and MCGowan volume, respectively. So far, equation [4] has been fitted to experimenta results in the laboratory, but not for results obtained in the field. Another objective of this work is to use for the first time pp-LFER to fit field measurments of soil-air partitioning, and explore the soil characteristics that affect the values of s, a, b, l and v that appear in equation [4].

2. Materials and methods Field measurments of soil concentrations, fugacity in soil and ambient air fugacities of PCBs, DDTs, HCHs, HCB and PAHs were performed in NW England, N and NE Spain and in the Antarctica Peninsula as has been described elsewhere (Cabrerizo et al. 2011a,b,c and Cabrerizo et al. 2012). Concurrent measurements of soil organic matter and other soil characteristics were also performed. 3. Results and discussion

10 γ-HCH Log KSA predicted, PAHs = 0.97(±0.056)logmeasured KSA+ 2.08(±0.336) R2 = 0.98

y = x SA 8 SA

6 Log K Predicted Log K Log KSA predicted, PCBs= 0.80(±0.20)logmeasured KSA+ 2.65(1.283) Log KSA= -71.28 + 22229 (±3582)* 1/T R 2 = 0.73 R2= 0.61 p<0.001 ΔH=80 ±13 N=27 30h 4 4 6 8 10 Measured Log KSA

Figure 1: Temperature dependence of KSA for Lindane for sites in Spain and England, and an example of soil-air partitioning of PCBs and PAHs in the Ebro river watershed versus predicted values using equation [3].

Figures 1 shows a couple of examples of the results obtained from the data set. The influence of

temperature on partitioning is significant for all compounds except HCB. Figure 1 also shows that KSA for PCBs and PAHs are lower than predicted values (from equation [3]) by one to two orders of magnitude. This suggests that the factor (ζoct/ζOM)(MW oct/MW OM) is significantly smaller than unity (between 1 and 2 orders of magnitude), a fact that is not account in current models and thus introduce an important error in their predictions. The values of (ζoct/ζOM)(MW oct/MW OM) to be used in models will be discussed as a function of chemical properties and environmental soil characteristics.

During the last decade, the use of pp-LSER has become popular for describing environmental partitioning, even though its use is mainly justified for polar compounds. In this work we will also address the potential advantage and to which degree a single equation such as equation [4] can be used for describing soil-air exchange in temperate and polar soils with diverse characteristics.

4 References

[1] Arp, H.P.H. R. P. Schwarzenbach, K.U. Goss. Ambient gas/particle partitioning. 1. Sorption mechanisms of apolar, polar, and ionizable organic compounds. Environ. Sci. Technol. 2008. [2] Cabrerizo, A.; Dachs, J.; Barceló, D. Development of a Soil Fugacity Sampler for Determination of Air−Soil Partitioning of Persistent Organic Pollutants under Field Controlled Conditions, Environ. Sci. Technol., 43, (21), 8257- 8263, 2009. [3] Cabrerizo, A.; Dachs, J.; Moeckel, C.; Ojeda, M.-J.; Caballero, G.; Barceló, D .; Jones, K. C., Ubiquitous Net Volatilization of Polycyclic Aromatic Hydrocarbons from Soils and Parameters Influencing Their Soil−Air Partitioning, Environ. Sci. Technol., 45, (11), 4740-4747, 2011. [4] Cabrerizo, A.; Dachs, J.; Moeckel, C.; Ojeda, M.-J.; Caballero, G.; Barceló, D.; Jones, K. C., Factors Influencing the Soil–Air Partitioning and the Strength of Soils as a Secondary Source of Polychlorinated Biphenyls to the Atmosphere, Environ. Sci. Technol., 45, (11), 4785-4792, 2011. [5] Cabrerizo, A.; Dachs, J.; Jones, K. C, Barceló, D. Soil-Air Exchange Controls on Background Atmospheric Concentrations of Organochlorine Pesticides. Submitted Atmospheric Chemistry and Physics. [6] Cabrerizo, A.; Dachs, J.; Barceló, D.; Jones, K. C. First field measurement of revolatilization of persistent organic pollutants from different compartments (snow, soil, vegetation) in the Antarctica austral summer. In preparation. [7] Finizio, A.; Mackay, D.; Bidleman, T.; Harner.T. Octanol-air partition coefficient as a predictor of partitioning of semi- volatile organic chemicals to aerosols. Atmos. Environ. 1997, 31, 2289-2296.

Acknowledgement - The authors thank the European Comission and the Spanish ministry of Science and Innovation for funding the AQUATERRA and ATOS project. A. Cabrerizo acknowledge a predoctoral fellowship from the Spanish Ministry of Science and Innovation. On the contribution of biomass burning to POPs in air in Africa

Gerhard Lammel1,2, Angelika Heil3, Irene Stemmler1, Alice Dvorská2

1Max Planck Institute for Chemistry, J.-J.-Becher-Weg 27, 55128 Mainz, Germany 2Masaryk University, Research Centre for Toxic Compounds in the Environment, Kamenice 3, 62500 Brno, Czech Republic 3Helmholtz Research Centre Jülich, Institute for Energy and Climate Research, 52428 Jülich, Germany E-mail contact: [email protected]

1. Introduction Forest, savannah and agricultural debris fires in the tropics and subtropics are sources for wide spread pollution and release many organic substances into air and soil [1], including persistent organic pollutants, i.e. polychlorinated dibenzodioxins and -furanes (PCDD/Fs) and polycyclic aromatic hydrocarbons (PAHs). The significance of this source for the exposure of humans and the environment is unknown. Does biomass burning constitute eventually a significant source for dioxins in the tropics?

2. Materials and methods We used the global multicompartment chemistry-transport model MPI-MCTM [2-3] to predict the gaseous and particle-associated atmospheric concentrations of selected PCDDs and PAHs. The model large-scale meteorology was constrained by nudging the atmospheric sub-model to re-analysis data (i.e., the historic weather; ECMWF). Global emissions of PAHs and PCDDs into air are based on recommended (PCDDs, e.g. [4]) and selected (PAHs) emission factors applied to fire distributions. Daily real-time fire data are based on satellite-observed fire radiative power measured from satellite (MODIS instrument) [5]. No other primary sources are considered. Photochemistry with the hydroxyl radical and ozone in the gas-phase and absorption in the particulate matter organic phase and adsorption to black carbon (PAHs [6]) are considered. Model-predicted near-ground concentrations of PCDDs and PAHs are compared with observations during January-June 2008 at a number of stations across Africa [7]. Back-trajectory analyses (HYSPLIT [8]) suggest that some of these had been influenced by fire episodes in the region.

2.1. Results and discussion Continental half-year (Jan-June 2008) mean near-ground atmospheric concentrations are 0.0076, 0.51 and 3.25 fg m-3 of 2,3,7,8-TCDD, 1,2,3,4,6,7,8-HpCDD and OCDD, respectively. Maxima are in the range 10-

Figure 1: Model-predicted distributions of 1,2,3,4,6,7,8-HpCDD from open fires in January (left column) and June (right column) at ≈1500 m height (upper row) and ground-level (lower row). 100 fg m-3 for 1,2,3,4,6,7,8-HpCDD and OCDD, one order of magnitude lower for 2,3,7,8-TCDD. It is found that open fires can explain a major fraction of the air pollution by PCDDs in the background of west, central and southern Africa. Open fire predicted levels of all PAHs exceed the observed levels at some of the stations by up to one order of magnitude, in rare occasions by up to two orders of magnitude. Exceedances can be explained by too high emission factors and/or neglect of photochemical degradation in the particulate phase. Highest concentrations of PCDD and PAH are predicted in 1-4 km altitude throughout most of the time, sometimes even higher and sometimes near the ground (Fig. 1). Biomass burning plumes are reportedly transported high, higher than industrial emission plumes [9]. Aloft, they are dislocated downwind, stretching far into the Gulf of Guinea (Fig. 1). Predicted open fires related PAH concentrations sometimes exceed observed levels. This can be explained by model input data uncertainties, namely PAH emission factors and chemical kinetics data for both the gas and particulate phases.

3. Conclusions

Open fires contribute significantly to the exposure of the African environment to PCDDs. The results support an at least regional long-range transport potential of PCDD/Fs, and also of PAHs (as suggested earlier [3]). The incomplete knowledge of chemical kinetics of gaseous and particle-associated PAHs is severely limiting source attribution and understanding of transport and fate [3,10]. Furthermore, PAH emission factors from biomass combustion sources should be better established, based on field and open burning facilities studies.

4. References [1] Andreae MO. 1991. Biomass burning: Its history, use, and distribution and its impact on environmental quality and global climate, in: Global Biomass Burning (Levine JS, ed.), Cambridge (MA), USA: MIT Press, pp. 3-21. [2] Semeena VS, Feichter J, Lammel G. 2006. Significance of regional climate and substance properties on the fate and atmospheric long-range transport of persistent organic pollutants – examples of DDT and γ- HCH. Atmos Chem Phys 6:1231-1248. [3] Lammel G, Sehili AM, Bond TC, Feichter J, Grassl H. 2009. Gas/particle partitioning and global distribution of polycyclic aromatic hydrocarbons – a modelling approach. Chemosphere 76:98-106. [4] UNEP. 2005. Standardized toolkit for identification and quantification of dioxin and furan releases, UNEP Chemicals, Genève, Switzerland: UNEP, ed. 2.1, 253 p. [5] Heil A, Kaiser JW, van der Werf GR, Wooster MJ, Schultz MG, Denier van der Gon H. 2010. Assessment of the real-time fire emissions (GFASv0) by MACC. Tech. Memo No. 628, Reading, UK: ECMWF. [6] Lohmann R, Lammel G. 2004. Adsorptive and absorptive contributions to the gas-particle partitioning of polycyclic aromatic hydrocarbons: state of knowledge and recommended parametrization for modeling. Environ Sci Technol 38:3793-3803. [7] Klánová J, Čupr P, Holoubek I, Borůvková J, Přibylová P, Kareš R, Tomšej T, Ocelka T. 2009. Persistent organic pollutants in Africa – 1. Passive air sampling across a continent-wide network 2008. J Environ Monit 11:1952-1963. [8] Draxler RR, Rolph GD. 2003. Hybrid Single-Particle Lagrangian Integrated Trajectory Model http://www.arl.noaa.gov/ready/hysplit4.html. Accessed 01 02 2011. [9] Ancellet G, Orlandi E, Real E, Law KS, Schlager H, Fierli F, Nielsen JK, Thouret V, Mari C. 2011. Tropospheric ozone production related to West African city emissions during the 2006 wet season AMMA campaign, Atmos Chem Phys 11:6349-6366. [10] Dvorská A, Lammel G, Klánová J. 2011. Use of diagnostic ratios for studying source apportionment and reactivity of ambient polycyclic aromatic hydrocarbons over Central Europe. Atmos Environ 45:420-427.

Acknowledgement - This research was partly supported by the Granting Agency of the Czech Republic and the European Commission, European Structural Funds (project CETOCOEN) and 7th FWP R&D (project ArcRisk). Abstract title (max 200 characters)

Miriam Diamond1,2, Emma Goosey1, Lisa Melymuk1, Susan Csiszar1, Golnoush Abbasi1, Sri Chaudhuri1, Paul Helm2

1University of Toronto, 45 St. George Street, Toronto, ON, M5S 3G3, Canada 2Ontario Ministry of the Environment, 125 Resources Road, Toronto, ON, M9P 3V6, Canada E-mail contact: [email protected]

1. Introduction It comes as little surprise that major cities in developed countries are important emissions points of myriad chemicals considering their large populations and numerous activities that take place there. Chemical contaminants from cities can enter the surrounding environment as a result of direct discharge of treated wastewater effluent from municipal and industrial sources and tributaries which inevitably are contaminated due to stormwater runoff and illegal sewer connections, and atmospheric deposition. Ultimately, these loadings can be traced back to human activities and the infrastructures we have built to enable these activities. Although individual emissions are minor individually, in aggregate they are significant because of the size of urban populations and the geographic aggregation of material use and discharge. This paper reviews results from studies we have conducted over several years in which we have aimed to connect chemical inventories and sources, to emissions and then fate. The framework we have built to describe this connection is useful for examining human and ecosystem exposures and, more importantly, opportunities to minimize exposures.

2. Materials and methods We have used multiple methods to bring together an integrated view of chemical transfer from product to its fate. Toronto, a city of 2.5 million located on the shores of Lake Ontario, has been our case study. First, we have compiled inventories of two chemicals, PCBs and PBDEs. The PCB inventory is based on government records. The PBDE inventory is based on product use, product replacement times and disposal practices, together with PBDE concentratiosn in those products. Second, we have conducted measurement campaigns for PCBs, PBDEs, “new” halogenated flame retardants, polycyclic musks, and PAH. Measurements have been made in indoor and outdoor air, indoor dust, rivers and wastewater treatment plant final effluent. Air sampling was done use PUF passive samplers at multiple locations in the and hi-vol samples at two locations. Surface waters were collected at high and low flow periods in order to obtain a representative dataset. Wastewater treatment plant final effluent was collected on on a few occassions. All samples were analysed using published methods and subject to QA/QC controls. Third, we have developed and applied a mass balance model to describe the fate of chemicals indoors and outdoors. Two outdoor models were used – our “simple”, 7-compartment, fugacity-based Multimedia Urban Model or MUM which was run assuming steady-state conditions, and a more complex coupled model. The coupled model consisted of a boundary layer metereological model tightly coupled to MUM, run assuming dynamic conditions using 25 km2 grid resolution.

3. Results and discussion

3.1. Inventory Results We estimated that as of 2008, Toronto held approximately 235 tonnes of PBDEs in products and 260 tonnes in vehicles. As shown in Figure 1, the greatest inventory was held in the Central Business District (CBD) which is the location of Toront’s financial district. The largest mass of PCBs held in Toronto in 2006 was also located in teh CBD.

3.2. Air Concentrations and emissions Air concentrations of PBDEs and PCBs were highest at the CBD (Figure 2). They were best described by building volume, dwelling count and e-waste recycling facilities. Not surprisingly, emissions to air were also greatest from the CBD (Figure 3), which was the same for PCBs.

Figure 1. Inventory of total PBDEs in Toronto, resolved into 25 km2 grids.

Figure 2. Concentrations of total PBDEs measured along north-south and west-east transects in Toronto.

Figure 3. Emissions to air of 4 PBDEs estimated using a coupled mesoscale meteorological model and the Multimedia Urban Model.

Text text text text text text text text text text text text text text text text text text. Text text text text text text text text text text text text text text text text text text. 4. Conclusions

Cities can be major point sources of chemical emissions through air, surface water and waste water treatment plant discharges. Using Toronto as a case study, we found that the Central Business District held the greatest inventory of PBDEs and PCBs, had the highest air concentrations and the higehst emissions to air. These results speak to the importance of non-industrial sources. This source profile is poorly served by pollution emission regulations and hence point to the need for preventative approaches to minimize releases.

5. References [1] Author AB, Author CD, Author EF. 1998. Title of article. J Agric Food Chem 22:11-33. [2] Author AB, Author CD. 1998. Title of book. City (ST), Country: Publisher. 00 p. [3] Author AB. 2004. Title. http://www.address.com. Accessed Day Month Year.

Acknowledgement - The authors thank ..... Exposure to airborne pollutants – experience from Danish studies OleHertel1,2, Steen S. Jensen1, Matthias Ketzel1, Thomas Becker1, Robert G. Peel1,3, Pia Viuf1,4, Carsten A. Skjøth1,5, Thomas Ellermann1, Ole Raaschou-Nielsen6, Mette Sørensen6, Elvira V. Bräuner6, Zorana J. Andersen6, Steffen Loft7, Vivi Schlünssen4, Jakob Bønløkke4, and Torben Sigsgaard4 1Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, DK 2Dep. Environmental, Social & Spatial Change, Roskilde University, Universitetsvej 1, 4000 Roskilde, DK 3National Pollen and Aerobiology research Unit, University of Worcester, UK 4Dep. of Public Health, Unit of Env. & Occ. Medicine, Aarhus University, Bartolins Allé 2, 8000 Aarhus C 5Dep. for Earth and Ecosystem Sciences, Lund University, Sölvegatan 12, 223 62 Lund, Sweden 6Danish Cancer Society, Strandboulevarden 49, 2100 Copenhagen East, DK 7Dep. for Public Health, Section Env. Health, Uni. of Copenhagen, Øster Farimagsgade 5A, 1014 CPH K, DK E-mail contact: [email protected]

1. Introduction Danish air pollutant (AP) levels are generally moderate due to windy climate and moderate emissions [1]. Despite this, DK epidemiological studies points at severe negative adverse health effects: stroke [1,2], lung cancer [3], COPD [4], asthma in adults [6], wheeze in infants {7,8], asthma hospital admission in children [9], oxidative stress in blood DNA [10], vascular function in elderly [11], AP enhance effects of radon on childhood leukaemia [12], and most recently diabetes[13]. These findings have been possible due to access to precise health data and advanced exposure assessment methods. Unique population and health registries in DK allow detailed health impact assessments to be carried out.

2. Materials and methods For assessing exposures, a GIS based modelling system, AirGIS (www.AirGIS.dk), has been developed [14]. AirGIS is originally aimed for traffic air pollution, but is under steady improvement and development [15,16] e.g. also to handle other pollutant emissions. The central part is Operational Street Pollution Model (OSPM)[17], currently applied in >17 countries worldwide [18]. Within the Danish research centre AIRPOLIFE (www.airpolife.dk), the AirGIS system was applied for exposure assessment for a variety of DK cohorts including the diet, cancer, & health cohort of 50,000 people. Measurements from the DK AP monitoring programmes and AirGIS calculations on address level have been used as exposure proxies in a series of publications to evaluate various negative health outcomes. The later were based either on data from health registers or biomarker measurements. Wood smoke is the largest source of particles emissions in Denmark, and health effects have been studied in chamber experiments [19], but not yet in epidemiological studies.

Ambient Health Emission Exposure Dose levels effect

Meteorology TrafficTraffic loads loads Demography Physiology Dose - Transformation CompositionComposition Time-activity Activity level response Topography SpeedSpeed patterns Street ColdCold start start Micro- configuration OtherOther sources sources environments Background Indoor/outdoor concentrations

3. Perspectives Wood smoke and emissions of aeroallergens (e.g. pollen, fungal spores, free allergens etc) from either agricultural activities or from vegetation are among the future aims for further development of AirGIS. Air pollution is believed to increase allergenic potential of airborne pollen [20] and risk of new sensitisation [21]. Traditionally, monitoring of aeroallergens is performed solely through sparse networks. Recent field studies have investigated exposure variability across an urban environment, and related chamber experiments have been applied to dose-response relationships for asthmatic people. Modelling strategies used in air pollution monitoring are currently being modified for aeroallergens, where the long-term goal is to incorporate aeroallergens within the AirGIS.

4. Conclusions

The Danish AirGIS system has proven to be a very strong tool in assessment of negative health effects of air pollution. This is seen in the fact that statistically significant associations are found between AirGIS address level air pollution exposure and health effects, and that these associations are stronger than what has previously been found when measurements from routine monitoring programmes have been used as exposure proxies.

5. References [1] Hertel O, Goodsite ME. Urban Air Pollution Climate Through out the World. In: Hester RE, Harrison RM, editors. Air Quality in Urban Environments. Cambrigde: RSC Publishing; 2009. 1-22. [2] Andersen ZJ et al. Traffic Related Air Pollution Associated with Mild Stroke Hospital Admissions in Copenhagen, Denmark. Epidemiology 2009; 20(6):S28-S29. [3] Andersen ZJ et al. Association between short-term exposure to ultrafine particles and hospital admissions for stroke in Copenhagen, Denmark. European Heart Journal 2010; 31(16):2034-2040. [4] Raaschou-Nielsen O et al. Air Pollution from Traffic and Risk for Lung Cancer in Three Danish Cohorts. Cancer Epidemiology Biomarkers & Prevention 2010; 19(5):1284-1291. [5] Andersen ZJ et al. Chronic Obstructive Pulmonary Disease and Long-Term Exposure to Traffic-related Air Pollution A Cohort Study. Am J Respir Crit Care Med 2011; 183(4):455-461. [6] Andersen ZJ et al. Long-term exposure to air pollution and asthma hospitalizations in elderly adults: a cohort study. In print for Thorax 2012. [7] Andersen ZJ et al. Time Series Study of Air Pollution Health Effects in COPSAC Children. 1005, -64. 2005. Copenhagen, DK, Danish EPA. Technical report in the series “Miljøprojekt”. [8] Andersen ZJ et al. Ambient air pollution triggers wheezing symptoms in infants. Thorax 2008; 63(8):710- 716. [9] Iskandar A et al.Coarse and fine, but not ultrafine particles in urban air trigger asthma hospitalizations in children. In print for Thorax 2011. [10] Bräuner EV et al. Exposure to Ultrafine Particles from Ambient Air and Oxidative Stress-Induced DNA Damage. Environmental Health Perspectives 2007; 115(8):1177-1182. (11) Brauner EV et al. Indoor particles affect vascular function in the aged - An air filtration-based intervention study. Am J Respir Crit Care Med 2008; 177(4):419-425. (12) Brauner EV et al. Is there any interaction between domestic radon exposure and air pollution from traffic in relation to childhood leukemia risk? Cancer Causes & Control 2010; 21(11):1961-1964. (13) Andersen ZJ, Raaschou-Nielsen O, Ketzel M, Jensen SS, Hvidberg M, Loft S et al. Diabetes incidense and long-term exposure to air pollution: a cohort study. In press for Diabetes Care 2012. (14) Jensen SS, Berkowicz R, Hansen HS, Hertel O. A Danish decision-support GIS tool for management of urban air quality and human exposures. Transportation Research Part D-Transport and Environment 2001; 6(4):229-241. (15) Ketzel M et al. Evaluation of AirGIS - a GIS based air pollution and human exposure modelling system. In press for J Environ Pollut 2011. (16) Jensen SS, Larson T, Deepti KC, Kaufman JD. Modeling traffic air pollution in street canyons in New York City for intra-urban exposure assessment in the US Multi-Ethnic Study of atherosclerosis and air pollution. Atmos Environ 2009; 43(30):4544-4556. (17) Berkowicz R. OSPM - A parameterised street pollution model. Environmental Monitoring and Assessment 2000; 65(1-2):323-331. (18) Kakosimos KE, Hertel O, Ketzel M, Berkowicz R. Operational Street Pollution Model (OSPM) - a review of performed application and validation studies, and future prospects. Environ Chem 2010; 7(6):485-503. (19) Riddervold IS et al. Wood smoke in a controlled exposure experiment with human volunteers. Inhalation Toxicology 2011; 23(5):277-288. (20) D'Amato G et al. Allergenic pollen and pollen allergy in Europe. Allergy 2007; 62(9):976-990. (21) Diaz-Sanchez D, Garcia MP, Wang M, Jyrala M, Saxon A. Nasal challenge with diesel exhaust particles can induce sensitization to a neoallergen in the human mucosa. Journal of Allergy and Clinical Immunology 1999; 104(6):1183-1188.

Insight into the primary and secondary organic fraction of the organic aerosol in an urban area: Barcelona

B.L. van Drooge, M. Alier, R. Tauler, J.O. Grimalt. Institute of Environmental Diagnostics and Water Research (IDÆA-CSIC), Jordi Girona 18, 08034 Barcelona, Catalonia, Spain E-mail contact: [email protected]

1. Introduction Monitoring and chemical analysis of atmospheric fine particulate matter (PM1) is important due to its health impact and influence on climate change (1,2). The air quality in the urban area of Barcelona in the Western Mediterranean Basin is assumed to be dominated by traffic related emissions and characterized by high levels of particulate matter and reactive chemical species due to emissions, the weak synoptic conditions and high solar radiation (3,4). Ambient air filter samples were collected during intensive sampling campaigns during 2009 and 2010 (DAURE and SAPUSS) on urban background (UB) and road sites (RS) and a rural background at 780 m (RB). The samples were analyzed for organic tracer compounds, e.g. polycyclic aromatic hydrocarbons, hopanes, alkanes, hydrosugars and nicotine, as well as secondary organic aerosols tracer compounds, e.g. dicarboxylic acids, for source characterization and identification of the organic patterns of primary and secondary aerosols. The obtained are compared with “on-line” data, such as those generated with Aerosol- Mass-Spectrometer. The results are discussed in terms of their relation to emission sources and influence of meteorological conditions in order to get an insight on the source contributions to the complex organic aerosol [5].

2. Materials and methods PM1 filter samples were collected with 12 or 24 hour resolution in background and road site in Barcelona (41º22”N; 2º11”E) and in a rural site in the Monseny natural park, using a Hivol-sampler. Polycyclic aromatic hydrocarbons, hopanes, alkanes, anhydrosugars, nicotine, and dicarboxylic acids were analyzed using GC-MS with TMS derivation of the polar compounds beforehand. Complementary data on OC/EC content of PM1, concentration levels of daily registered O3 and NOx levels as well as meteorological conditions, and air-mass trajectories for the sampled days were recorded. High resolution Aerosol Mass Spectrometer data was available to relate results of on-line and off-line techniques. Moreover, statistical tools, such as PCA (Principal Component Analysis) and MCR-ALS (Multivariate Curve Resolution - Alternating Least Squares), were used to analyze the variance in the database.

3. Results and discussion

Organic tracer compound levels and their relation with meteorological conditions and emission sources In the urban area, PCA analysis showed strong correlations between organic compounds separating them in two component groups: those related to primary emissions and those related to secondary aerosols and biomass burning. MCR-ALS analysis was able to resolve five components. The first and second components were related to anthropogenic activities (traffic and tobacco smoke) that were more intense in RS. The third component was related to regional air mass circulation and consequently accumulation of secondary aerosols. The forth component was related to biomass burning in combination with regional air mass circulation. A fifth component could be related to food cooking activities. The organic tracer compounds, representing the five identified components correlated very well with the organic aerosol analyses of the HR-AMS. From these analyses it was estimated that in UB about 50% of OA is secondary, and probably mainly biogenic, while this was about 40% in RS. Primary sources, mainly traffic, contributed to about 30% to the OA in UB and about 50% in RS. Biomass burning was of minor importance in the city, while food cooking contributed to about 20% of the OA.

4. Conclusions The concentration variability of PM1 in an urban background area of the Western Mediterranean Basin is supported by the concentration trends of organic tracer compounds and can partially be explained by changes of meteological conditions and the strenght of anthopogenic and natural emission sources. The complex mixture, and often simultaineous concentration trends of the different tracers, complicates the intepretation of results, chemometric tools were able to distinguish the most important source for the organic aerosol in this area, indicating that primary (traffic) and secondary organic aerosols are the most important contributors to the organic aerosol, but food cooking could also have a significant share.

5. References [1] IPCC, 2007, ISBN: 978 0521 88009-1. [2] Pérez et al., 2009. Environ. Sci. Technol. 43, 4707-4714. [3] Millán et al., 1997. J. Geophys. Res. 102, 8811-8823. [4] Pérez et al., 2010. Aerosol. Sci. Technol. 44, 487-499. [5] Alier et al., 2011. in preparation.

Acknowledgement – Financial support from the scientic research projects GRACCIE (CSD2007-00067), AER-TRANS (CTQ2009-14777-C02-01), SAPUSS (FP7-PEOPLE- 2009-IEF), DAURE (CGL2007-30502-E/CLI) are acknowledged, as well as the Geosciences departement of IDAEA. The role of bioavailability in risk reduction of contaminated sites

Joop Harmsen

Alterra, Wageningen UR, P.O.Box 47, 6700 AA Wageningen The Netherlands E-mail contact: [email protected]

1. Introduction Most regulations and regulatory accepted assessment procedures on soil and sediment contamination are still based on total concentrations. When removal of the contaminant is an expensive exercise and/or there are doubts on the risks posed by the contaminants this often leads to a “wait and see” attitude. Site investigations are often repeated, but no actions are taken to reduce the risks of the contaminants, an infinite circle (figure 1). From a risk-based point of view, contaminations are only a risk if they are or may become (bio)available. This widens the range of management options of contaminated sites and can facilitate more tailor-made solutions for individual sites. In a risk based approach stimulation of biodegradation and/or immobilization and isolation of the contaminant may play a role. In particular bioavailability can be the underlying basis for the description of risks and for determining a solution and can be used to break the infinite assessment circle.

Figure 1 The assessment circle Because bioavailable fraction poses risks this fraction should be as small as possible. This can be achieved in a number of ways including the removal of contaminants. It is not sufficient to remove the actual available fraction, because this will be replaced quickly by the reservoir of contaminants in the potential available fraction. So removal will mean removal of the potential available fraction. On the other hand, the contaminant in the water phase (actual available) is responsible for direct effects as accumulation in vegetation, effects on soil living organisms and leaching to groundwater. If this amount is reduced, risks are also reduced. Thus the key to managing contaminated sites could be via bioavailability reduction to a point that even the presence of residual contaminants does not result in release of available fraction. Bioavailability should be more than a concept and including bioavailability in site management asks for methods to measure the bioavailable fraction. Such methods should have an understandable physical base (ISO 17402 [1]) and are fortunately available. Using a method that measures the potential available fraction risks can be predicted. If contaminants are biodegradable this is also the fraction that can be degraded. If contaminants are not biodegradable, the bioavailability can be reduced by immobilization, for instance by adding black carbon [2] or by preventing leaching and physical contact by isolation.

2. Case studies

2.1. Reduction of bioavailability by stimulation of biodegradation Fortunately a lot of organic contaminants like mineral oil and polycyclic aromatic hydrocarbons (PAHs) are biodegradable. The biodegradable fraction of PAHs can be estimated using a method that measures the potential available fraction. Tenax [3] has been used at 20°C and 60°C and results represent the fast, slow and very slow avilable fractions. These data can be used as input in a simple degradationmodel (sum of three first order degradations) and predict the degradable amount [4]. A result is presented in figure 2, showing that the prediction is reliable. The model underestimates the biodegradation, but in practise the organic matter content of the treated sediment was also reduced during treatment, which reduces the possibility of absorption of PAH. The figure also shows that a long time can be necessary to remediate contaminated soil and sediment using biodegradation. This has consequences for the use of biodegradation in remediation. It is necessary have a beneficial use of the site during the remediation. Growing of biomass is an option. An extra advantage of growing vegetation is stimulation of the bioactivity in the soil by creating the proper conditions.

Figure 1 Biodegradation of PAHs in Petroleumharbour sediment on a landfarm, measured and predicted by a model based on measured bioavailble fractions.

2.2. Reduction of bioavailability by immobilization and isolation If contaminants are not biodegradable, the bioavailability can be reduced by immobilization, for instance by adding black carbon or by preventing leaching and physical contact by isolation. These possibilities have been applied to support management of remote pesticide contaminated areas in Africa. Locally available charcoal has been used for immobilization of deldrin. Natural dune formation combined with stimulation of vegetation to evaporate water thereby preventing leaching has been used for isolation [5].

3. Conclusions

Bioavailability can be used as a tool to reduce the risks of contaminated sites. To do this it is essential that during the assessment, methods are used that give understandable results. The obtained knowledge on bioavailability is necessary to design the remediation..

4. References [1] ISO, 2008. ISO 17402. Soil quality — Requirements and guidance for the selection and application of methods for the assessment of bioavailability of contaminants in soil and soil materials. [2] Koelmans, A.A., M.T.O. Jonker, G. Cornelissen, T.D. Bucheli, P.C.M. Van Noort and O. Gustafsson (2006) Black carbon: The reverse of its dark side. Chemosphere 63(3), 365-377. [3] Cornelissen, G., H. Rigterink, M.M.A. Ferdinandy and P.C.M. van Noort, 1998. Rapidly desorbing fractions of PAHs in contaminated sediments as a predictor of the extent of bioremediation. Environ. Sci. Technol. 32(7): 966-970. [4] Harmsen, J., W.H. Rulkens, R.C. Sims P.E. Rijtema and A.J. Zweers, 2007. Theory and application of landfarming to remediate PAHs and mineral oil contaminated soils and sediments, J. Env. Quality, 36, 1112- 1122. [5] Harmsen, J., M. Ammati, M. Davies, C. H. SYLLA T. SIDIBE, H.K. TRAORE A. DIALLO and A. SY Demba, 2009. An African Approach for Risk Reduction of Soil Contaminated by Obsolete Pesticides. In: G.B. Wickramanayake and H.V. Rectanus (Chairs), In Situ and On-Site Bioremediation—2009. Tenth International In Situ and On-Site Bioremediation Symposium. Paper E-15. Effect of activated carbon, biochar and compost on the desorption and the biodegradation of low concentrations of phenanthrene sorbed to different soils Geoffrey Marchal 1, Kilian E.C. Smith 1, Arno Rein 2, Anne Winding 1, Stefan Trapp 2, Ulrich G. Karlson 1

1 Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark. 2 Department of Environmental Engineering, Technical University of Denmark, Miljøvej building 113, 2800 Kgs. Lyngby, Denmark E-mail contact: [email protected]

1. Introduction Soil and groundwater remediation is aimed at reducing levels of pollutants to below regulatory thresholds. Polycyclic aromatic hydrocarbons (PAHs) are an important class of soil pollutants. Often, a large portion of the PAHs are degraded by soil microorganisms within short times (<100 days), and this is followed by slower degradation resulting in a non-degradable residual fraction remaining above the regulatory levels (Reichenberg et al., 2009). However, the bioavailability of these less accessible and bound PAHs can be low, implying a reduction in uptake by organisms and as a consequence a reduced potential for ecotoxicological effects. Soil amendments such as activated charcoal (AC), biochar (charcoal) and compost have been shown to reduce the freely dissolved concentrations of PAHs. On the one hand this might limit the bioavailability and uptake by organisms leading to reduced toxicity. On the other hand this might also decrease their biodegradation. The aim of this study was to characterize AC, charcoal and compost for their ability to reduce the freely dissolved concentrations of phenanthrene as a model PAH in three different sandy loam soils (from Flakkebjerg, Denmark), and to quantify their effect on phenanthrene desorption and mineralization.

2. Materials and methods

2.1 Sequential abiotic phenanthrene desorption The experiments investigating the abiotic desorption of phenanthrene (Phe) from the soil plus amendment suspensions were conducted in 20-mL glass vials (n=5). These contained 5 mL of a 20 g L-1 soil suspension (either Outfield, RS or Olsen soils) and 0.2 g L-1 of soil amendment (either AC, charcoal or compost) made up in minimal salt solution (MSS) and spiked with [9-14C] Phe at 100 µg L-1 (specific radioactivity 0.32 MBq mg-1 phenanthrene). Five clean silicone O-rings were added to each vial as a sink to trap the desorbed Phe, and these replaced intervals by 5 new clean O-rings. The vials were shaken for 24 days at 150 rpm and room temperature, and at t = 0.5, 1, 2, 3, 5, 6, 12, 18 and 24 days the 14C in the silicone O-rings extracted and analysed to determine the amount of Phe desorbed.

2.2 Phenanthrene mineralization assay Microbial mineralization of Phe sorbed to the soil plus amendments was tested in sterile 20-mL glass vials (n=5). These contained 5 mL of 20 g L-1 RS soil and 0.2 g L-1 of either AC, charcoal or compost. The suspensions were made up in MSS, and spiked with [9-14C]Phe at 100 µg L-1. The PAH degrading Sphingomonas sp. (DSM 12247) was added at an initial cell density of 9 x 105 cells mL-1. The flasks were 14 incubated at room temperature on a horizontal shaker at 150 rpm for 15 days, and the CO2 produced measured at t = 1, 2, 3, 5, 7, 10 and 15 days (= Phe mineralized). At the end of the experiment, the 14C in suspension was measured (= Phe sorbed, degradation products, and incorporated into biomass). The cell density and concentrations of parent Phe in suspension measured using HPLC (= non-degraded Phe) were determined at t = 0.25, 0.5, 0.75, 1, 1.5, 2, 3, 5, 7, 10, and 15 days.

3. Results and discussion The total amount of Phe abiotically desorbed was 6 to 10% for AC, 38 to 44% for charcoal, 87 to 106% for compost, and 95 to 106% for control without any soil amendments (Figure 1). The nature of the soil had a minor effect on the extent of abiotic desorption, and only for the long term experiment (RS soil and compost). The mineralization of Phe sorbed to the soil amendments by Sphingomonas sp is shown in Figure 2. The 14 percentage of initial C found in the CO2-trap at experiment completion was 3.0 to 5.4% for AC, 10.4 to 14.8% for charcoal, 14.9 to 21.8% for compost, and 25.5 to 31.2% for control. The peak of phenanthrene mineralization and biodegradation was correlated with a peak of bacteria growth at the same period (between t = 2 and 3 d, data not shown). The mineralization rate and cell density dropped down after day 3 and both remained constant until the end of the experiment (t = 15 d).

Soil Outfield Soil RS Soil Olsen

100 100 100

AC 80 80 80 charcoal 60 compost 60 60 control 40 40 40

20 20 20 cumulative desorbed (%) PHE cumulative desorbed (%) PHE cumulative desorbed (%) PHE 0 0 0 0 5 10 15 20 25 0 5 10 15 20 25 0 5 10 15 20 25 time (day) time (day) time (day)

Figure 1: Sequential abiotic desorption of 14C phenanthrene, as a % of the initial radioactivity, from the AC, biochar or compost plus soil (either Outfield, RS, or Olsen) suspensions in MSS to the silicone O-rings. The controls were soil suspensions without any soil amendment.

30

AC 20 charcoal compost control

Phe mineralized (%) mineralized Phe 10

0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 time (days) Figure 2: Mineralization of 14C phenanthrene, as a % of initial radioactivity, in RS soil suspensions with either AC, biochar or compost in MSS. The controls were soil suspensions without any soil amendment.

4. Conclusions Sorption to the AC and biochar soil amendments had a strong inhibitory effect on desorption, mineralization, and biodegradation. This was in contrast to compost which only had a small effect on desorption but a larger inhibitory effect on mineralization and biodegradation. The sequential abiotic desorption approach into an infinite silicone sink can be used as a tool to estimate the readily desorbable phenanthrene fraction, and thus the extent of phenanthrene desorption from the different soil plus amendment suspensions. These were similar to the amounts of phenanthrene that were mineralized which implies that desorption approach can also be used to estimate the maximal extent of phenanthrene mineralization. Finally, reducing the extent of phenanthrene desorption by adding soil amendments leads to a decrease in mineralization and biodegradation by reducing the freely dissolved concentrations as well as bioaccessibility of phenanthrene.

5. References [1] Reichenberg F, Karlson U G, Gustafsson Ö, Long S M, Pritchard P H, and Mayer P. 2009. Low accessibility and chemical activity of PAHs restrict bioremediation and risk of exposure in a manufactured gas plant soil. Environ Pollut 158:1214-1220.

Acknowledgement - The authors thank the Danish Council for Strategic Research, project ‘‘Innovative REMediation and assessment TEChnologies for contaminated soil and groundwater’’ (REMTEC). The authors thank Lis Wollesen de Jonge for providing the soils. The influence of field aging of activated carbon in sediment on PCB sorption in field trials

Amy Oen1, Barbara Beckingham2, Yeo-Myoung Cho3, David Werner4, 1 5 3 Gerard Cornelissen , Upal Ghosh and Richard Luthy

1Norwegian Geotechnical Institute, 0806 Oslo Norway 2University of Tübingen, 70274 Tübingen Germany 3Stanford University, Stanford CA 94305 USA 4 Newcastle University, Newcastle upon Tyne NE1 7RU United Kingdom 5University of Maryland Baltimore County, Baltimore MD 21250 USA E-mail contact: [email protected]

1. Introduction Bioavailability of hydrophobic organic contaminants of concern such as polychlorinated biphenyls (PCBs) in sediments is strongly influenced by the nature of contaminant binding. This observation is at the foundation of utilizing the sorption capacity of activated carbon (AC) to control risks posed by sediment-associated contaminants. Monitoring over several years at pilot-scale field application sites at Hunters Point, California and Grasse River, New York USA has demonstrated that AC amendment reduces contaminant bioavailability by controlling both chemical accessibility and activity [1,2]. Some previous studies have suggested that sorption of target contaminants to activated carbon in sediments, at least initially, may be diminished due to fouling of the activated carbon surfaces and pore openings, especially with natural organic matter (NOM) [3,4]. Thus, one important question that needs to be further studied is the long-term sustainability of this remediation strategy under field conditions.

2. Materials and methods To further evaluate the sorption effectiveness of AC after prolonged exposure in the field, sorption of freshly spiked and native PCBs to 1) AC aged for 2-2.5 years under field conditions and 2) fresh AC amendments to untreated sediments were compared for sediments collected from both pilot sites in Grasse River and Hunters Point. Thus for both sites, three sediment-AC combinations were examined: non-amended reference sediment, reference sediment with freshly added AC, and sediment containing field-aged AC. Pore water concentrations and sorption coefficients (KAC) were determined by batch systems containing sediments, water and polyoxymethylene passive samplers which were shaken for 30 d (Grasse River tests) to 90 d (Hunters Point tests) in the laboratory. Batch tests contained a spike of 3 different unique PCBs not present at the field sites. Values of KAC were determined using a two-carbon model (such as presented in [2]) and assuming a Freundlich coefficient of n=0.8. In a separate study, a mass transfer model was invoked to simulate the effectiveness of AC amendment to reduce pore water concentration with field aging of AC at Hunters Point [5]. This model includes an attenuation factor to account for reduced sorption coefficients for PCBs to AC in sediment compared to clean water systems. Modeling output for an observation-based hypothetical sediment column with a randomly assigned AC distribution was compared to pore water concentrations measured using an aqueous batch technique at 4 time points up to 5-years post-amendment [5]. The details of the model will not be presented, but insights drawn from this separate modelling study may help explain results from the sorption tests.

3. Results and discussion

3.1. Sorption to fresh and field-aged AC After 24-30 months of field aging, AC amendment demonstrated reduced pore water concentrations of both native (30-95%) and spiked (10-90%) PCBs compared to unamended sediment. Pore water reduction of spiked PCBs for freshly amended Grasse River sediment decreased with increasing congener hydrophobicity which may show that the 30-d laboratory contact was not sufficient to reach thermodynamic equilibrium in these batch tests. Values of KAC for field-aged AC were lower than freshly-added AC for spiked PCBs up to a factor of 10, while the effect was less for native PCBs. For both Hunters Point and Grasse River field-aged AC, similarly diminished sorption compared to fresh AC for the spiked PCBs was observed (Table 1). However, there was a greater decrease in sorption coefficients compared to values for fresh AC for most of the native PCBs in the Grasse River sediment which is likely due to the nearly ten-times higher organic carbon content of Grasse River sediment.

Grasse River Hunters Point Literature Compound Fresh Field-Aged Compound Fresh Field-Aged AC AC AC AC Values Values for in Water DOM-loaded PCB-14* 7.4 ± 0.1 6.2 PCB-29* 6.9 ± 0.1 6.3 ± 0.3 PCB-65* 8.0 ± 0.4 6.6 PCB-69* 7.2 ± 0.1 6.1 ± 0.2 PCB-166* 7.6 ± 0.2 6.7 PCB-103* 7.0 ± 0.1 5.7 ± 0.1 PCB-18 7.0 ± 0.1 6.7 PCB-18 - - 8.233 7.523 PCB-(52+43) 7.1 ± 0.04 6.8 PCB-(52+49) 6.5 ± 0.3 6.3 ± 0.3 7.823 7.033 PCB-101 6.9 ± 0.2 6.7 PCB-101 6.8 ± 0.3 6.6 ± 0.2 PCB-153 7.3 ± 0.4 6.5 PCB-153 6.9 ± 0.3 6.7 ± 0.3 PCB-180 7.4 ± 0.4 7.7 PCB-180 7.3 ± 0.2 6.9 ± 0.1 * Indicates spiked PCBs

Table 1: Determined log KAC (n=0.8) values for AC in sediments for native and extra-spiked PCBs compared to literature values

3.2. Modeling PCB mass transfer at Hunters Point For early time-points (0.5 and 1.5 years post-application) the simulation results tended to under-predict the reduction in aqueous pore water concentration for AC treated sediments while after longer time (3.5 and 5 years) the model over-predicted effectiveness [5]. This phenomenon may be due to more fouling of AC sorbents with time with natural organic matter (NOM). Early after amendment, the mass transfer of NOM from sediment to AC would be likely kinetically retarded by the same mass transfer limitations for PCBs. However, NOM exhibits greater concentration, mobility and smaller retardation by sorption processes in the aqueous phase compared to PCBs. Diffusion through NOM at AC pore openings presents an additional mass transport limitation for PCBs. Changing kinetic limitations for PCB mass transfer over time may explain the different effects of field aging observed for AC sorption of native and spiked PCBs at Hunters Point and Grasse River. The AC does not lose sorption capacity, yet incremental improvements may slow with time.

4. Conclusions

Site characteristics such as the contaminant desorption kinetics and NOM quality and quantity will be important considerations when designing sustainable remediation strategies with AC amendment. Importantly, these studies show that aged amended AC continues to effectively sorb PCBs several years following field application.

5. References [1] Cho Y-M, Ghosh U, Kennedy AJ, Grossman A, Ray G, Tomaszewski JE, Smithenry DW, Bridges TS, Luthy RG. 2009. Field application of activated carbon amendment for in-situ stabilization of polychlorinated biphenyls in marine sediment. Environ Sci Technol 43:3815-3823. [2] Beckingham B, Ghosh U. 2011. Field-scale reduction of PCB bioavailability with activated carbon amendment to river sediments. Environ Sci Technol In Press doi:10.1021/es202218p [3] McDonough KM, Fairey JL, Lowry GV. 2008. Adsorption of polychlorinated biphenyls to activated carbon: Equilibrium isotherms and a preliminary assessment of the effect of dissolved organic matter and biofilm loadings. Wat Res 42:575-584. [4] Hale, SE, Tomaszewski JE, Luthy RG, Werner D. 2009. Sorption of dichlorodiphenyltrichloroethane (DDT) and its metabolites by activated carbon in clean water and sediment slurries. Wat Res 43:4336-4346. [5] Cho Y-M, Werner D, Choi Y, Luthy RG. 2011. Long-term monitoring and modeling of the mass transfer of polychlorinated biphenyls in sediment following pilot-scale in-situ amendment with activated carbon. J Contam Hydrol In Press doi:10.1016/j.jconhyd.2011.09.009

Acknowledgement - The authors wish to acknowledge funding sources, including the U.S. Department of Defense Strategic Environmental Research and Development Program and Environmental Security Technology Certification Program, the Southwest Division Naval Facilities Engineering Command, the Chevron Energy Company, the Liverhulme Trust, the Research Council of Norway KMB program, the National Institute of Environmental Health Sciences (NIEHS) Superfund Research Program and Alcoa. Impact of biochar on the biodegradation and bioavailability of organic contaminants in soils

Ogbonnaya Uchenna1, Semple Kirk1, Thomas James1, Howell Chris2

1Lancaster Environment Centre, Lancaster University, LA1 4YQ, UK. 2Warwick Life Sciences, Wellesbourne campus, University of Warwick, CV35 9EF, UK. Email contact: [email protected]

1. Introduction The behaviour of chemicals in the environment varies according to many parameters such as physicochemical properties, concentration, soil properties, soil-contaminant contact time, and environmental factors. Total bioremediation of contaminants is difficult and expensive to attain. Therefore, in order to mitigate the risk an organic contaminant may pose, the bioavailable/bioaccessible fraction of the contaminant has to be investigated and reduced. This is because the overestimation of risk may be inferred on basis of the total concentration of the chemical in the environment, without taking into account the bioavailability, thermodynamics or transport (pathway) under prevailing conditions.

The soil organic matter (SOM) has been reported as an important factor in controlling the adsorption and bioavailability of hydrophobic organic contaminants (HOCs) but may further be mineralised or degraded by microorganisms and would eventually release such organic contaminants. The coupling of pollutants to humus of SOM may form more toxic compounds such as dioxins and furans (Bosma and Harms, 1996). The potential use of recalcitrant biochar (pyrolysed organic matter) to mitigate the risk of exposure to organic contaminants will be a useful tool for risk practitioners.

The aims of the research were: - To assess the impact of biochar on the biodegradation and extraction of PAHs and pesticide in soils. - To assess if particle size of biochar and soil properties have effect on the sorption behaviour of contaminants in soil upon aging. - To investigate the use of different extraction techniques to predict the biodegradation of PAHs in biochar amended soil.

2. Materials and Methods 2.1 Soil amend and spiking Uncontaminated soil (loam to clay loam) was used in this study and was spiked separately with 12 and 14C- naphthalene, phenanthrene and azoxystrobin following Doick et al (2003). The soils were then amended with 0%, 0.1%, 0.5% and 1% of two different wood biochars (BC1 and BC2) and then aged in dark for 0, 18, 36 and 72 days (naphthalene), 0, 35, 70, 140 days (azoxystrobin), 0 and 40 days (phenanthrene). BC1 was produced by the slow pyrolysis of mixture of wood waste at 450oC for 16 hours. BC2 was produced by fast pyrolysis of demolition wood waste at 1000oC for 1 hour.

2.2 Mineralisation of 14C-naphthalene, phenanthrene and azoxystrobin in soil The mineralisation was performed in modified 250 ml Schott bottles using the method described by Reid et al (2001). The respirometers incorporate a Teflon lined screw cap and a CO2 trap containing 1 M NaOH (1 ml) within a 7 ml glass scintillation vial. After each aging period, respirometers were prepared in triplicate with 10 ± 0.2 g soil containing 0%, 0.1%, 0.5%, and 1.0% biochar (BC), 25 ml minimal basal salt (MBS) solution, and 5 ml isolated azoxystrobin-degrading inoculums bacteria (108 cells/g soil). The respirometers were o 14 placed on an orbital shaker and set at 100 rpm and 25 C over a period of 20 d. Evolved CO2 as a result of 14C-chemical catabolism was trapped in 1 M NaOH. The 14C activity was assessed every 24 h for 14 d by liquid scintillation counting.

2.3 Extraction of 14C-naphthalene, phenanthrene and azoxystrobin-associated activity by Hydroxypropyl- β-Cyclodextrin (HPCD), Calcium chloride (CaCl2) and Methanol Determination of 14C-naphthalene, phenanthrene and azoxystrobin extractability using HPCD (50 mM), CaCl2 (10 mM) was carried out at each sampling point as described by Reid et al (2000). Soils were weighed into 30 ml Teflon centrifuge tubes (n=3) at 1:20, 1:15 and 1:15 ratio to HPCD, CaCl2 and methanol solution. The tubes were placed onto an orbital shaker at 100 rpm for 24 h. The tubes were then centrifuged at 3500 rpm for 1 h (Rotanta 460 Centrifuge, Hettich, Germany) and 5 ml supernatant was pipetted into 20 ml glass scintillation vials containing Goldstar scintillation cocktail (14 ml). The 14C-labeled radioactivity in the resultant solution was then quantified using the liquid scintillation counting.

Statistical analysis was done using SigmStat version 3.5 software

3 Results and discussion 3.1 Mineralisation Results confirmed that the addition of biochar had a significant impact (p < 0.01) on the total extent of mineralisation of 14C-naphthatlene and phenanthrene during and after the aging period. However, BC2 showed greater effect on the reduction in extent of naphthalene mineralisation at all contact times, which was more observed with the 1% BC2 (p < 0.001). This was probably due to greater surface area and larger distribution of pore volume (micropores). This study supports Rhodes et al (2010), where soils amended with 1 and 5% activated carbon exhibited significantly lower rates and extent of 14C-phenanthrene mineralisation compared to non-amended soils. Additionally, 2 mm BC1 significantly reduced mineralisation of phenanthrene to a greater extent than 3-7 mm BC1 at high concentrations (5-10%). Little or no mineralisation of 14C-azoxystrobin occurred with all amendments of BC.

3.2 Extraction The HPCD extraction closely mimics the mass transfer mechanism that governs bioavailabilty of nonplanar organic compounds (Stokes et al., 2005). The HPCD extraction represents the rapidly desorbing fraction of the compound which is labile fraction. Biochar amendment in soils significantly (p < 0.01) reduced all the extractability of 14C-naphthalene, phenanthrene and azoxystrobin in soil. The 0.5% and 1% BC1 significantly (p < 0.01) reduced the HPCD and CaCl2 extraction of naphthalene in soil, methanol extraction was significantly reduced at only 1% BC1 amendment. However all amendments of BC2 significantly (p < 0.01) reduced the extractability of naphthalene and azoxystrobin to a larger extent compared to 0% amendment and all BC1 amendments. This reduction was further expressed upon aging.

The authors discovered that even with biochar amendments in soils containing 14C-naphthalene and phenanthrene, there was strong relationship between the extent of mineralisation to HPCD extraction. These results suggest that HPCD extraction can predict extent of PAH mineralisation and not the rate of mineralisation. Results also showed that methanol and CaCl2 extractions overestimated and underestimated extent of PAH mineralisation respectively.

4. Conclusions Biomass waste can be used to produce biochar. The biochar used was not subject to any form of chemical activation, which requires high energy and production cost. However, it was shown to be a viable tool in adsorbing PAHs and azoxystrobin, thereby mitigating the risk of such contaminants. Furthermore, it did not affect the capability of HPCD to predict the mineralisation of phenanthrene in soils unlike activated carbon. Thus, biochar can be used as a cheap tool for remediation purposes, depending on the concentration, particle size, production process and soil physiochemical properties. Further research is required to investigate the effect of wood biochar on complex mixtures of pesticides, heavy metals and PAHs it’s stability in locking up contaminants.

References Bosma, T. and Harms, H. 1996. Bioavailability of Organic Pollutants. EAWAG News 40E, 28 – 31.

Doick, K. J., Dew, N. M. and Semple, K. T. 2005. Linking catabolism to cyclodextrin extractability: Determination of the microbial availability of PAHs in soil Environmental Science and Technology. 39, 8858 - 8864.

Stokes, J. D., Wilkinson, A., Reid, B. J., Jones, K. C. and Semple, K. T. 2005. Predictions of polycyclic aromatic hydrocarbon degradation in contaminated soils using an aqueous hydroxypropyl-β-cyclodextrin extraction technique. Environmental Toxicology and Chemistry. 24, 1325 - 1330.

Toxicity and bioavailability of geogenic polycyclic aromatic compounds from coal

Wiebke Meyer1,2, Thomas-Benjamin Seiler2, Andreas Christ1, Mathias Reininghaus2, Jan Schwarzbauer3, Wilhelm Püttmann4, Henner Hollert2 and Christine Achten1

1University of Münster, Institute of Geology and Paleontology - Applied Geology, Corrensstraße 24, 48149 Münster, Germany 2RWTH Aachen University, Institute for Environmental Research, Worringerweg 1, 52076 Aachen, Germany 3RWTH Aachen University, Institute of Geology and Geochemistry of Petroleum and Coal, Lochnerstraße 4- 20, 52056 Aachen, Germany 4Goethe University Frankfurt, Institute for Atmospheric and Environmental Sciences, Analytical Environmental Chemistry, Altenhöferallee 1, 60438 Frankfurt/Main, Germany E-mail contact: [email protected]

1. Introduction Coals contain native polycyclic aromatic compounds (PAC) that are generated during the diagenetic process of coal formation. Specific compounds and amounts of PAC present in coals are highly varying and depend on different coal properties, e.g. origin, coal rank or biological precursor material [1,2]. As a result of longterm mining activities and usage of coal as an energy source, soils and sediments worldwide can be highly contaminated by unburned coal particles [3]. Most polycyclic aromatic hydrocarbons (PAH) that occurred in coal-rich river floodplain soils were associated with coal particles [5]. Following, bioavailability and toxic effects of PAC from coals are matters of concern for the ecotoxicological risk assessment of soils and sediments. To date, performed studies on this topic (reviewed in [6]) lead to the present assumption of no or very low bioavailability as a result of coal acting as a very strong sorbent for hydrophobic compounds [7]. However, in these studies, highly varying properties of different coals were not taken into account. Additionally, besides polycyclic aromatic hydrocarbons (PAH) heterocyclic aromatic compounds (NSO-PAC) were not or hardly considered which are also known for their toxicity. Finally, the assumption of no or low biovavilability of PAC from unburned coal particles is hardly considered or applied in tasks of remediation of PAC-contaminated soils and sediments that also contain coal particles. As a consequence, the goals of the conducted study are: • the verification of the assumption of no/low biovailability of coal-derived PAC for different coal samples of explicitly varying properties which are expected to impact future risk assessment and remediation tasks • the consideration of heterocyclic aromatic compounds (NSO-PAC) in this context • the identification of former less or unknown toxic PAC

2. Materials and methods Subbituminous (n = 2), bituminous (n = 5) and anthracite (n = 1) coals of varying origin, coal rank and biological precursor material were ground (<200 µm). For chemical analysis, coal samples were extracted (pressured liquid extraction) and after removal of asphaltenes separated into an aliphatic, aromatic (PAH) and heterocyclic (NSO-PAC) fraction. The latter two were analyzed by gas chromatography-mass spectrometry and gaschromatography coupled with atmospheric pressure laser ionisation-ultra high resolution mass spectrometry (GC-APLI-UHR-QTOF-MS). For assesssing biovailability and effects of the bioavailable fraction, contact assays with fish embryos of Danio rerio and the nematode Caenorhabditis elegans using ground coal samples as a substrate were performed. For determination of the potential toxicity of coal extracts, both extract fractions were used in these assays as well as in additional test systems (Neutral red retention assay, EROD assay, Ames fluctuation assay) in liquid medium. Furthermore, a bioaccumulation test with the freshwater oligochaete Lumbriculus variegatus was performed.

3. Results and discussion PAH analysis of 40 PAH (16 EPA-PAH and other known toxic compounds, e.g methylated PAH and dibenzopyrenes) in the aromatic fractions of coal extracts showed considerably increased PAH concentrations (up to 120.1 mg/kg) EPA-PAH and 210.7 mg/kg (40 PAH). Only traces of PAH could be extracted from the anthracite (0.4 mg/kg EPA-PAH and 0.5 mg/kg 40 PAH). In a sub-bituminous coal from Germany, very high concentrations (>500 mg/kg) of alkylated chrysenes and picenes were found besides negligible PAH concentrations (2.8 mg/kg EPA-PAH; 6.4 mg/kg 40 PAH). The aromatic and heterocyclic fractions of all coal extracts except the anthracite exhibited dioxin-like activity, cytotoxic effects. For bituminous coals effects of the aromatic fractions were stronger than effects of heterocyclic fractions. Bio-TEQs (calculated from EROD activity with TCDD as reference substance in the positive controls) of the aromatic fractions of bituminous coals were up to 162,333 pg/g. Bio-TEQs of heterocyclic fractions were lower, but also noticeable. For sub-bituminous coal extracts, heterocyclic fractions leads to higher toxicity. According to the performed Ames fluctuation assay, all aromatic fractions (except anthracite sample) and heterocyclic fractions of the bitumious coals revealed mutagenic activity. Both fractions of all (except the anthracite sample) coal extracts were toxic in assays in liquid medium for D. rerio, the aromatic fractions were toxic for C. elegans. Results of the contact assays were different (Figure 1a and 1b): While the whole coal samples led to no mortality in the fish embryo assay (0 to 2.5%), inhibition of of C. elegans reproduction was 83 to 96% induced by the different coal samples. Results of the bioaccumulation test and the analysis by GC-APLI-UHR-QTOF-MS will be presented.

100 subbituminous coals 100 bituminous coals

[%] 80 anthracite 80

60 elegans C. 60 D.rerio

40 40 reproduction [%]

Mortality 20 20 Inhibition of no mortality no mortality no mortality no mortality 0 0 ID ID GB PL GB PL DE-1 ZA-1 ZA-2 DE-2 DE-3 DE-1 ZA-1 ZA-2 DE-2 DE-3 coal sample coal sample

Fig 1a: Mortality of D. rerio embryos after 48 h exposure to Fig 1b: Inhibition of reproduction of C. elegans after 96 h whole coal samples in contact assays; n=2 (independent exposure to whole coal samples in contact assays; n=3 assays) (independent assays)

4. Conclusions

The results show that extracts of the different coals induce various toxic effects in all used test systems due to high toxic PAC concentrations present in the extracts. From the results of the fish embryo assay, we conclude that there is no bioavailability of PAC from all coal samples leading to any lethal effect despite high potential toxicity of present PAC. The adverse effects of coal samples in the nematode contact assays are suspected to result from damages caused by the physical properties of the particles.

5. References [1] Achten, C., Hofmann, T. 2009. Native polycyclic aromatic hydrocarbons (PAH) in coals – A hardly recognized source of environmental contamination. Sci Tot Environ 407: 2461-2471. [2] Laumann, S., Micic, V., Kruge, M.A., Achten, C., Sachsenhofer, R.F., Schwarzbauer, J. Hofmann. T. 2011. Variations in concentrations and compositions of polycyclic aromatic hydrocarbons (PAHs) in coals related to the coal rank and origin. Environ Pollut 159: 2690-2697. [3] Johnson, R., Bustin, R.M. 2006. Coal dust dispersal around a marine coal terminal (1977–1999), British Columbia: The fate of coal dust in the marine environment. Int J Coal Geol 68: 57–69. [5] Pies, C. Hoffman, B., Petrowsky, J. Yang, Y. Ternes, T.A. Hofmann, T. 2008. Characterization and source identification of polycyclic aromatic hydrocarbons (PAHs) in river bank soils. Chemosphere 72: 1594–1601. [6] Ahrens, M.J., Morrisey, D.J. 2005 Biological effects of unburnt coal in the marine environment. Oceanogr Mar Biol Annu Rev 43: 69-122. [7] Achten, C., Cheng, S., Straub, K.L., Hofmann, T. 2011. The lack of microbial degradation of polycyclic aromatic hydrocarbons from coal-rich soils. Environ Pollut 159: 623-629 Adsorption of organic contaminant from aqueous solution on natural porous material

Salomé Ansanay-Alex1, Coralie Soulier2, Claire Lomenech1, Charlotte Hurel1, Nicolas Marmier1 and Hélène Budzinski2

1University of Nice Sophia Antipolis, ECOMERS, Parc Valrose, 28 avenue Valrose, 06108 Nice cedex 2, France 2 University Bordeaux1, EPOC-LPTC, UMR CNRS 5805, 351 Cours de la Libération, 33405 Talence Cedex, France E-mail contact: [email protected]

1. Introduction In the last few years, the problem of water pollution and particularly the pollution control became a priority in Europe, leading to the adoption in 2000 of the Water Framework Directive (WFD). This directive requires the improvement of the quality of the aquatic environment for 2015 [1]. In this context, the European Union countries promised to reduce or eliminate substances posing health risk to human and to the aquatic environment. In this study, we were interested in organic contaminants, especially medicines and pesticides that are among the most common contaminants in water. Actually, large amount of medicines are excreted in stools and urine and released in wastewater. The wastewater treatment plants are not yet able to remove medicines. Residual pharmaceuticals products are then transported with effluent toward surface waters. Pesticides, which are currently used for agriculture, are very common organic contaminants. Their resistance to physical and biochemical degradation make them particularly hazardous for the environment. Many studies have reported the presence of these compounds in surface waters, ground waters and in drinking waters [2-3]. In order to eliminate these contaminants, various removal processes exist: nanofiltration, reverse osmosis, ozonation, electrochemical oxidation, biological degradation and adsorption. Adsorption is the most popular method because of its high efficiency and its low-cost. The active carbon is the most commonly used adsorbent. However, its regeneration is complicated and expensive. For these reasons, researchers investigate to develop alternative adsorbents for the removal of organic pollutants from waters. In this context, we have investigated the adsorption capacity of different natural porous materials for pesticides and medicines.

2. Materials and methods

2.1. Soils Three natural Zeolites (Clinoptilolite, Mordénite, Chabazite) and one clay (Sepiolite) were selected as potential sorbent. Zeolites are hydrated aluminosilicates belonging to the family of tectosilicates. They are constituted with SiO4 and AlO4 tetrahedra forming a rigid three-dimensional framework with nanometer-sized channels and cages in which every molecule with a dimension inferior to 10Å can be fixed. Sepiolite is a special clay mineral belonging to the family of hydrated silicate of magnesium constituted of an alternation of two dimensional tetrahedral sheet of SiO4 boarding a two dimensional octahedral sheet of MgO6. The particularity of Sepiolite is that the octahedral sheet of MgO6 constituting its structure is not continuous, forming a framework of ribbons and channels of 3.6 × 10.6 Å allowing penetration of organic and inorganic molecules. This configuration gives to the Sepiolite a very important specific area of 320 to 340 m²/g.

2.2. Chemicals The sorption experiments were realized with a multi-compounds solution of medicines and pesticides. We have selected one pesticide (Diuron) and one pesticide belonging to the triazine family (Deisopropylatrazine) and one medicine (Diazepam) for sorption investigation.

2.3. Methods Sorption studies were performed using batch method [4]. All experiments were carried out in 50 mL polypropylene tubes by mixing a known amount of adsorbent with a solution containing the desired concentration of pesticides and pharmaceuticals at fixed pH (7.0 ± 0.1) and a fixed ionic strength (10-2 mol.L- 1 NaCl). The suspensions were shaken using a tube rotator at 50 rpm during 24h then the solids were separated from the aqueous solution by centrifuging at 3000 rpm during 10 min and the supernatant was removed by solid-phase extraction then analysed.

3. Results and discussion The results of adsorption experiments of the 3 compounds were presented in Figure 1. The results showed the sepiolite is only solid presenting a normal profil of adsorption which increases with increasing solid- solution ratio. This effect can be explained by the increase of available adsorption sites with the increase of adsorbent mass.

Diuron Deisopropylatrazine -8 5x10 7,0x10-8

-8 4x10-8 6,0x10 -8 clinoptilolite 5,0x10 -8 clinoptilolite 3x10 mordenite -8 sepiolite 4,0x10 mordenite sepiolite chabazite -8 2x10-8 3,0x10 chabazite 2,0x10-8 1x10-8 1,0x10-8 adsorbed concentration (mol/L) adsorbed concentration (mol/L) 0 0,0 0,00 0,01 0,02 0,03 0,04 0,05 0,00 0,01 0,02 0,03 0,04 0,05 solid-solution ratio (g/mL) solid-solution ratio (g/mL)

Diazepam

2,5x10-8

2,0x10-8 clinoptilolite

-8 mordenite 1,5x10 sepiolite chabazite 1,0x10-8

5,0x10-9 adsorbed concentration (mol/L) 0,0 0,00 0,01 0,02 0,03 0,04 0,05 solid-solution ratio (g/mL)

-8 -8 -8 Figure 1: Adsorption of Diuron (C0= 4.6x10 mol/L), deisopropylatrazine (C0=7.2x10 mol/L) and diazepam (C0=2.8x10 mol/L) on zeolites and sepiolite

4. Conclusion

Whatever is the studied compound, the adsorption curves have shown the same profile. Sepiolite presents a great efficiency of adsorption in comparison with the three zeolites and can be selected for its potential use in water treatment. In order to understand the mechanism of adsorption of different pesticides and pharmaceuticals on this selected adsorbent, complementary adsorption experiments as a function of contact time and concentration of contaminant should be performed.

5. References [1] Directive n° 2000/60/CE du 23/10/00 établissant un cadre pour une politique communautaire dans le domaine de l'eau. (23/10/2000) [2] Fatta, D., Michael, C., Canna-Michaelidou, S., Christodoulidou, M., Kythreotou, N., and Vasquez, M. 2007. Pesticides, volatile and semivolatile organic compounds in the inland surface waters of Cyprus. Desalination 215: 223-236 [3] Claver, A., Ormad, P.a., Rodriguez, L., and Ovelleiro, J.L. 2006. Study of the presence of pesticides in surface waters in the Ebro river basin (Spain). Chemosphere 64: 1437-1443. [4] [USEPA] U.S. Environmental Protection Agency. 1991. Batch-type procedures for estimating soil adsorption of chemicals. EPA/530-SW-87-006-F Novel pathways in the adsorption of weak organic acids by black carbon leading to ionization constant shifts on the surface J.J. Pignatello

Department of Environmental Sciences, The Connecticut Agricultural Experiment Station; 123 Huntington St., P.O. Box 1106; New Haven, Connecticut, USA. [email protected]

1. Introduction Black carbon (BC) is a natural component of soils and sediments, and the use of manufactured BC (activated carbons, biochars) has been proposed as a remediation tool. A fundamental understanding of the adsorption mechanisms of contaminants to BC is a prerequisite to technological control. Although many contaminants are ionic or ionizable over the normal environmental pH range, little attention has been paid to the interaction of such compounds with BC. Here I show examples of weak organic acids that adsorb to BC by unconventional mechanisms. We studied the adsorption to biochars of the allelopathic aromatic acids (AA), cinnamic (pKa 4.44) and coumaric (pKa 4.39) and the veterinary antibiotic sulfamethazine (SMT) (pKa1 0 + − ± 1 2.28, pKa2 7.42; existing as SMT , SMT , SMT , or SMT ). Adsorption of coumaric and cinnamic acids was investigated as part of a study of the effects of biochar application on the bioavailability of natural signalling chemicals in soil. Adsorption of SMT2 was part of a broader study on whether biochar application to soils could reduce SMT bioavailability and thus lower the threat of antibiotic resistance gene transfer between soil microorganisms.

2. Results and discussion

2.1. Aromatic Acids The biochar (Agrichar, BEST Energies) was produced by slow pyrolysis of Eucalyptus litter at 600 o 2 -1 C. The N2 specific surface area is 427 m g . Sorption isotherms of the AAs in pH 7 buffer, where the AAs are >99% dissociated, are highly nonlinear, give distribution ratios as high as 104.8 L/kg, and are insensitive to Ca2+ or Mg2+. In unbuffered media sorption becomes progressively suppressed with loading and is accompanied by release of OH− with a stoichiometry approaching 1 at low concentrations, declining to about 0.4 - 0.5 as the pH rises. Sorption of cinnamate on graphite as a model for charcoal was roughly comparable on a surface area basis, but released negligible OH−. A novel scheme is proposed that explains the pH dependence of adsorption and OH− stoichiometry and the graphite results (Figure 1). In a key step, AA− undergoes proton exchange with water. To overcome the unfavorable proton exchange free energy, which is not compensated by the increase in hydrophobicity, AA engages in a type of H bond with a surface carboxylate or phenolate group having a comparable pKa recognized to be of unusual strength. This bond is … … − depicted as [RCO2 H O-surf] where the proton is shared almost evenly between the O atoms. Such “low barrier H bonds” rank among the strongest known in organic chemistry. The same complex is possible for AA−, but is less favorable because it results in an increase in surface charge. The proton exchange pathway of adsorption appears open to other weak organic acids, including humic substances, on carbonaceous materials.

R-CO2 + H2O R-CO2H + HO

O O + R-CO2H O 1/2 1/2 O H O C R O OH O R-CO2 +

Figure 1: Pathway of aromatic acid anions adsorption on black carbon.

2.2. Sulfamethazine Adsorption of SMT on Agrichar was determined as a function of concentration, pH, inorganic ions, and organic ions and molecules. Despite its hydrophilic nature (log Kow = 0.27), the distribution ratio Kd at pH 5, 0 6 -1 4 where SMT prevails, was as high as 10 L kg , up to 10 times greater than literature reported Koc. The Kd decreases at high and low pH, but not commensurate with the decline in Kow of the ionized forms. The proposed evolution in SMT speciation on black carbon with pH is shown in Figure 2. At pH 1, where SMT+ is predominant and the surface is positive, rather than ordinary charge pairing, a major driving force is π-π electron donor-acceptor interaction of the protonated aniline ring with the π-electron rich graphene surface, referred to as π+-π EDA. This was demonstrated by competition experiments contrasting charged aliphatic with charged aromatic amines, and uncharged π-acceptors with uncharged π-donors. In the alkaline region, where SMT− prevails and the surface is negative, adsorption is accompanied by near-stoichiometric proton exchange with water, leading to the release of OH−. As in the case of AA, the increase in hydrophobicity due to protonation is not sufficient to overcome the unfavorable proton exchange free energy. Thus, as for AA, we postulate the formation of “low barrier H-bond” between SMT0 and a surface carboxylate or phenolate … … − 0 group, depicted as [-SO2N H O-surf] . At pH 5, SMT adsorption is accompanied by partial proton release and is competitive with trimethylphenylammonium ion, signifying contributions from SMT+ and/or the zwitterion, SMT±, which take advantage of π+-π EDA interaction and coulombic attraction to deprotonated surface groups. Thus, in essence, both pKa1 and pKa2 increase—the latter by an estimated 3 units—and SMT± is stabilized, in the adsorbed state relative to the dissolved state.

Figure 2: Proposed evolution of SMT speciation on black carbon with pH.

3. Conclusions

We conclude that adsorption of weak organic acids on black carbon surfaces can result in appreciable shift in ionization constants on the surface driven by the formation of strong complexes, such as low barrier H bonds and π+-π EDA interactions.

4. References [1] Ni, J.; Pignatello, J. J.; Xing, B. Adsorption of Aromatic Carboxylate Ions to Charcoal Black Carbon is Accompanied by Proton Exchange with Water,. Environ. Sci. Technol. 2011, 9240-9248. [2] Teixido, M.; Pignatello, J. J.; Beltran, J. L.; Grenados, M.; Peccia, J. Speciation of the Ionizable Antibiotic Sulfamethazine on Black Carbon (Biochar). Environ. Sci. Technol. ASAP.

Acknowledgement - The author thanks all the co-investigators named in the references and the University of Massachusetts, Amherst; Fujian Normal University, China; the Universitat de Barcelona; and the National Science Foundation CBET 0853682. Contribution of microbial biomass to non-extractable residue formation from an organic contaminant

Karolina Nowak1, Anja Miltner1, Andreas Schäffer2, Matthias Kästner1

1UFZ - Helmholtz-Centre for Environmental Research, Department of Environmental Biotechnology, Permoserstr. 15, 04318 Leipzig, Germany 2Institute for Environmental Research (Biology V), RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany E-mail contact: [email protected]

1. Introduction Biodegradation of organic contaminants in soil results in the formation of various metabolites, mineralisation products (CO2 and H2O), microbial biomass and non-extractable residues (NER). NER are believed to be formed via various physicochemical interactions (e.g. covalent bonding or sequestration) of the parent contaminant and its metabolites with the soil matrix, particularly with soil organic matter (SOM; [1]). Due to the complexity of the soil system these physicochemical mechanisms of NER formation were studied in simple model systems containing only the contaminants and humic acid solutions [2]. In soils, however, BR analyses in most cases are limited to quantitative analyses based on mostly radio isotope mass balances [1]. Therefore, the chemical composition of NER formed from biodegradation of organic contaminants in soil is still unclear. During biodegradation of organic contaminants, the C is used by microorganisms for synthesis of their biomass compounds such as fatty acids (FA) and amino acids (AA). After cell death and lysis, these components are stabilised in SOM ultimately forming harmless biogenic residues. However, this pathway has not been considered yet. Biogenic residues thus could be included in the NER fraction in radio-isotope mass balance studies. This results in an overestimation of pollutant-derived NER, and thus of the environmental risk associated with them. We investigated the formation of 13C-labelled FA and AA during 13 biodegradation of 2,4-dichlorophenoxyacetic acid ( C6-2,4-D) in soil and traced their fate during 64 days of incubation.

2. Materials and methods An agricultural soil taken from a long-term experiment was incubated in the dark and at 20°C for 64 days [3]. The soil systems were sampled destructively after 2, 4, 8, 16, 32 and 64 days of incubation and analysed for the amount and the isotopic composition of FA and AA in two fractions: in the living biomass fraction (PLFA or bioAA) and in the total fraction of SOM (tFA or tAA). The difference between the incorporations of the label into the living and total fractions of SOM represents the presence of the label in the respective compound group in non-living SOM fractions. The accumulation of the label in the non-living SOM provides information about the stabilisation of biogenic residues FA in the living SOM fraction (PLFA) were extracted with a mixture of phosphate buffer, methanol and chloroform [4] and separated from neutral lipids and glycolipids by column chromatography over silica gel [5]. Finally FA were derivatised with methanol/trimethylchlorosilane [5]. FA in the total SOM fraction were directly derivatised in the same way as the PLFA. After derivatisation, methylated tFA were extracted from soil with diethyl ether and purified over silica gel columns [5]. AA from proteins in the total SOM were hydrolysed with 6 M HCl for 22 hours at 110°C [6]. After hydrolysis, samples were purified over cation exchange resin [3]. After purification, the carboxyl groups of AA were esterified with a mixture of isopropanol/acetyl chloride and the amino groups were trifluoroacetylated with a mixture of dichloromethane/trifluoroacetic acid anhydride [6]. For the determination of the AA in the living biomass, the biomass was first extracted from the soil with Chelex 100 and sodium deoxycholate/polyethylenglycol solution [6]. Biomass pellets containing AA were further hydrolysed, purified and derivatised as AA in the total SOM. The FA and AA in both fractions were identified and quantified after separation on a BPX-5 column by means Gas Chromatography-Mass Spectrometry; their isotopic composition was determined by Gas Chromatography Combustion-isotope ratio Mass Spectrometry [3]. 3. Results and discussion This study provides the first evidence for a significant contribution of microbial residues to NER formation 13 13 from C6-2,4-D. The C-label was detected in FA and AA in both living and non-living fractions of SOM 13 which clearly indicated a biogenic origin of NER [3]. Since C6-2,4-D was biodegraded rapidly, incorporation of the 13C-label into FA and AA in the living fractions was fast. The highest amount of 13C-FA in the living 13 13 SOM was detected on day 4 (0.7% of the initially added C6-2,4-D equivalents; [3]), whereas C-AA were 13 highest on days 4 and 8 (2.2 and 2.5% of C6-2,4-D equivalents, see Fig.1). Thereafter, their contents decreased continuously until the end of the incubation, and the label was incorporated into the non-living SOM pool. The contents of 13C-FA in non-living SOM decreased to 50% of their maximum indicating their metabolisation and their further distribution within the food web [3]. Contrary to the FA, 13C-AA in the non- living SOM were surprisingly stable demonstrating a rapid stabilisation of AA from the decaying microbial 13 13 biomass. At the end, the amount of C in tAA was high, reaching 22% of the initially added C6-2,4-D equivalents. It is known that proteins containing AA are the most abundant components (~ 50% of dry mass) of bacterial cells [3]. Therefore, the total content of biogenic residues derived from this 13C-labelled pesticide could be determined by correction of the amount of 13C found in the tAA considering the conversion factor of 13 two for proteins [3]. At the end of incubation nearly all of the C6-2,4-D-derived NER could be explained by microbial compounds (Fig. 2).

100% 25 90% 80% 20 Mineralisation 70% Extractable 15 60% 50% 10 40% BR 30% Biogenic residues* 5 NER20% C-label distribution in soil (%)

D equivalents (% of applied) 10% 13

- Proteins 0 0% 2,4 0 10 20 30 40 50 60 2 4 8 16 32 64 incubation time (days) incubation time (days)

Fig. 1. 13C-label incorporation into tAA ( ) and Fig. 2. Mass balance including biogenic residue 13 13 bioAA ( ) during biodegradation of C6-2,4-D [3]. formation during biodegradation of C6-2,4-D [3].

4. Conclusions 13 The results show that NER derived from C6-2,4-D can be completely explained by harmless biogenic components. This contradicts the generally accepted view that all NER formed during biodegradation of organic contaminants in soil are composed of hazardous parent compounds or their primary metabolites [1]. Therefore, it is necessary to consider a possible formation of biogenic residue from readily degradable contaminants in future mass balances in order to estimate properly the potential risks of the respective contaminant in soil.

5. References [1] Barriuso E, Benoit P, Dubus IG. 2008. Formation of pesticide nonextractable (bound) residues in soil: magnitude, controlling factors and reversibility. Environ Sci Technol 42: 1845-1854. [2] Hatcher PG, Bortiatynski JM, Minard RD, Dec J, Bollag JM. 1993. Use of high-resolution 13C-NMR to examine the enzymatic covalent binding of 13C-labeled 2,4-dichlorophenol to humic substances. Environ Sci Technol 27: 2098-2103. [3] Nowak KM, Miltner A, Gehre M, Schäffer A, Kästner M. 2011. Formation and fate of bound residues from microbial biomass during 2,4-D degradation in soil. Environ Sci Technol 45: 999-1006. [4] Bligh EG, Dyer WJ. 1959. A rapid method of total lipid extraction and purification. Canad J Biochem Phys: 37, 911-917. [5] Miltner A, Richnow HH, Kopinke FD, Kästner M. 2004. Assimilation of CO2 by soil microorganisms and transformation into soil organic matter. Org Geochem: 35, 1015-1024. [6] Miltner A, Kindler R, Knicker H, Richnow HH, Kästner M. 2009. Fate of microbial biomass-derived amino acids in soil and their contribution to soil organic matter. Org Geochem: 40, 978-985. Acknowledgement - The authors thank the European Commission for funding the RAISEBIO Project (Contract: MEST-CT-2005-020984) under the Human Resources and Mobility Activity within the 6th Framework Programme, in particular the fellowship of K. M. N. We also thank Dr. M. Gehre and U. Günther (UFZ, Department of Isotope Biogeochemistry) for assistance in the compound-specific isotope analysis and Dr. H.-H. Richnow for providing the possibility to analyse the samples in his laboratory.