Long-Term Monitoring of Persistent Organic Pollutants (Pops) at the Norwegian Troll Station in Dronningland, Maud Antarctica R

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Climate Sum chlordanes. Sciences Sciences > Dynamics Chemistry of the Past Solid Earth -DDT, DDD, DDE as Techniques throughout the entire Geoscientific Methods and ˚ and Physics Alesund, Svalbard) in Atmospheric Atmospheric Atmospheric p Data Systems Geoscientific 3 , Earth System Earth System Measurement Instrumentation − Hydrology and o , S. Manø Ocean Science Annales Annales Biogeosciences 1 The Cryosphere Natural Hazards Hazards Natural and Earth System System Earth and Model Development Sum DDT Geophysicae - and 0 > p , p , C. R .Lunder 1 Sum PCB > Open Access Open Access Open Access Open Access Open Access Open Access Open Access Open Access Open Access Open Access Open Access Open Access Open Access 6220 6219

Climate Sum HCH , S. Eckhardt Sciences Sciences Dynamics 1 Chemistry > of the Past Solid Earth 1,3 Techniques Geoscientific Methods and and Physics Advances in Advances Atmospheric Atmospheric Atmospheric Data Systems Geoscientific Geosciences Earth System Earth System Measurement Instrumentation Hydrology and Ocean Science Biogeosciences The Cryosphere Natural Hazards Hazards Natural EGU Journal Logos (RGB) EGU Journal and Earth System System Earth and Model Development , K. Breivik , and A. Stohl 1,2 1 ˚ As, Norway The POP levels determined in Troll air were compared with 1 concentrations found This discussion paper is/has beenand under Physics review (ACP). for Please the refer journal to Atmospheric the Chemistry corresponding final paper in ACP if available. Department of Chemistry, University of Oslo, Oslo, Norway Norwegian Institute of Air ResearchDepartment (NILU), of Kjeller, Norway Chemistry, Biotechnology and Food Sciences (IKBM), Norwegian University of in earlier measurement campaigns18 at yr. other Except Antarctic for researchall HCB stations sampling for campaigns, from which concentrations the in similarsamples past the concentration collected recent distributions during Troll samples were theously were observed a early lower than in direct 1990s. in consequence Theselike of chemicals concentration international on reductions regulations a are worldwide restricting scale. obvi- the usage of POP- Troll samples analyzed: HCB Atmospheric long-range transport wasPOPs identified in as a Antarctic majorlevels environments. of contamination pesticides Several source and/or long-range for compoundsretroplume with transport industrial calculations events sources with were a with identified Lagrangian based elevated particle on dispersion model (FLEXPART). 3 Received: 27 September 2012 – Accepted: 11Correspondence February to: 2013 R. – Kallenborn Published: ([email protected]) 8 MarchPublished 2013 by Copernicus Publications on behalf of the European Geosciences Union. well as hexachlorobenzene (HCB) weresamples selected. taken The during monitoring the program period withat 2007–2010 weekly was the coordinated Norwegian with Arctic the parallelterms monitoring program site of (Zeppelin priority mountain, compounds,POP Ny- concentration sampling levels schedule found asmospheric in background well Antarctica concentrations. as Similar were as analytical considerablythe observed methods. lower predominant for POP than Arctic The compound samples, Arctic with HCBmonitoring at- levels is period. of In around general, 22 pg the m following concentration distribution was found for the A first long-term monitoring of selectedair persistent has organic been pollutants conducted (POPs) at in the Antarctic As Norwegian Research target station Troll contaminants (Dronning Maud 32 Land). trans- PCB and congeners, cis-chlordane, a- trans- and and g-hexachlorocyclohexane cis-nonachlor, (HCH), M. Schlabach 1 2 Life Sciences, Abstract Long-term monitoring of persistent organic pollutants (POPs) at the Norwegian Troll station in DronningLand, Maud Antarctica R. Kallenborn Atmos. Chem. Phys. Discuss., 13, 6219–6246,www.atmos-chem-phys-discuss.net/13/6219/2013/ 2013 doi:10.5194/acpd-13-6219-2013 © Author(s) 2013. CC Attribution 3.0 License. 5 25 15 20 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | = ¨ oller et al., 2011). orts to minimize this ff SCAR Group of Specialists = Persistent Organic Pollutants). = 6222 6221 airs and Conservation, etc.). ff Therefore, in 2007, the Norwegian Institute for Air Research (NILU) in collaboration Until today, the establishment of long-term continuous atmospheric monitoring of The current comprehensive Arctic long-term atmospheric POP monitoring programs, with the Norwegian Polar Institute (NPI) initiated the first long-term atmospheric moni- Hemisphere, levels of POPs have beenlower previously considered than as in extremely the low – Arctic.as much However, a Antarctica location attracts for more pollutantAntarctic and research. environments more reveal Studies scientific clearly on interest that potentialtion the local levels anthropogenic is contamination impact not issues on negligible Antarctic in hu despite pollu- of man considerable impact international by e Scientific means Committee of on international Antarcticon regulations, Research, Environmental bans GOSEAC A and restrictions (SCAR mospheric long-range transport of POPs inin the particular high-latitude for Southern the Hemisphere Antarctic and that continent. potential The above-mentioned primary earlierHemisphere studies sources contribute indicated (agriculture, to industrial thedue releases POP to the levels etc.) remoteness of in in Antarctica the and the few Antarctic potential industrial Southern atmosphere. sources Nevertheless, in the Southern spherical transport and fate of legacy POPs and emergingPOPs so-called in new POPs. Antarctica has beenrestrictions (e.g. seriously remoteness hampered and cost by intensive political,several logistics). economic campaign-based During the and studies past logistical two on decades, ing short-term of POPs (weeks–month) in atmospheric Antarctica1998; monitor- have Dickhut et been al., reported 2005; in GambaroThus, et the al., only literature 2005; (Kallenborn Xie scattered et et scientific al., al., 2011a,b; information M 1995, has been available for the evaluation of at- programs such as the ArcticNations Monitoring Economic and Commission Assessment for Programmegramme Europe (AMAP), (UNECE-EMEP), European United Monitoring Global andet Atmospheric Evaluation al., Watch 2001). Pro- Thus, (GAW) the and experiencethat with this others the type past (Holoubek 20 of yr data of is monitoring urgently in the required Arctic for proved a scientifically sound evaluation of hemi- tic monitoring data are continuously reported to regional and international monitoring restriction of POP usage and distribution (Rodan et al., 1999; Clapp, 2003). The Arc- They are considered asatmospheric the transport central and scientific distribution2008; Aas basis processes et al., for (Dutchak 2008) the and anddistribution are processes empirical Zuber, important (Wania, 2010; investigation for 2003; the UNEP, Wania of evaluationIn and of Mackay, combination models 1999; simulating with Armitage global meteorological etatmospheric al., modeling, 2006). long-range the transport continuous events monitoringregulative as measures reveals also may well be asassessed. appropriate potential This when information source international is regions,tions today mitigation where in an strategies order important to are resource provide the for scientific the basis global for POP appropriate counter regula- measures for global 2010). in particular at the Zeppelin stationpressively and the the importance Canadian of Alert these researchof station, national long-term proved commitments im- for atmospheric the POPs continuous operation monitoring (POPs spheric transport of anthropogenicpolar research pollution, (ACIA, radiation 2005). Furthermore, asling the well release, physico-chemical hemispheric as mechanisms transport, control- cryospherecan distribution related be and examined deposition in of greatet target detail contaminants with al., the 2011; help ofregions AMAP, long-term 2009). of monitoring Long-term of our pollutants atmospheric globeassessing (Ma pollution is anthropogenic monitoring today influences considered in onnational as the regulation the valuable measures environment polar and (Kallenborn as versatile and well scientific Berg, as 2009; tool controlling UNEP, for inter- 2011; Hung et al., Polar regions are considered today ascesses important sentinels for for many global scientific environmental pro- tions disciplines are still involved characterized in by minimum environmentalregions anthropogenic research. for presence comprehensive and, Polar thus, baseline loca- are studies suitable including global circulation systems, hemi- 1 Introduction 5 5 25 20 10 15 25 15 20 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | C) prior to anal- ◦ 20 − cially opened in 2005 and a compre- resulting in sample volumes between ffi 1 − E, at 1270 m.a.s.l. in the Nunatak area of h 0 3 32 6224 6223 ◦ and He, 6.0 quality, Porsgrunn, NO). 2 S, 2 0 01 ◦ The sample preparation method was optimized based on an Samples were collected from February 2007 until December 2010 After the sampling was completed, the exposed filters (GFF and . A commercially available high volume air sampling device (DHA-80, POP sampling was performed at the Troll Atmospheric Observatory, 3 ˚ Alesund, Svalbard) in terms of sampling schedule, sampling and an- 50 µm, Schleicher-Schuell, Dassel, GER). Gas- and particle phase samples ff Sample preparation. Sample storage. Sample collection. all gases were provided by Hydro (N program). All exposed filters wereysis registered and and quantification. stored frozenaustral The ( summer yearly (November) sample toand set the airfreight was analytical transport. laboratory shipped in on Norway the by first combinedearlier ship flight described every method (Kallenborn etare al., given 2006). in the Details Supplement on of theof the preparation paper. highest All methods solvents, quality adsorbents and available, gasesand well used adsorbents suited were were purchased and from selected Merck (Spurenanalyse for quality, Darmstadt, ultra-trace GER), analysis. Solvents PUF) were sealed in a gasfor tight container further for storage processing and transport andprior to quantification. to NILU’s laboratory No analysis manualblank of samples treatment/exposure the followed is the filters. required yearlynation In risks sample (as addition, batch a extensive in part of order numbers the to of extensive control quality field control potential procedure contami- and of the transport NILU monitoring plugs (PUF) whereas the particle phaseid, was cut-o collected on glass fiberwere filters collected (GFF: 10 simultaneously. cm Flow-rate andtored sampling and conditions documented were (e.g. power digitally failures,quality moni- etc.) control as procedure. integrated Sector part controlled of samplingpassing the was over performed sampling the where and main air research masses the station potential was for avoided/not local collected contamination. in order to minimize on a weekly basis.were For collected the with monitoring, a continuous2200 flow and integrated rate 2500 m weekly/7-days of samples 10–15DIGITEL, m Hegenau, CH) for separate particlemonitoring and gas of phase POPs. collection was The used gas for the phase was collected on pre-cleaned polyurethane foam ing in 2006/2007 (e.g. POPs).for Data POP from monitoring the are first presented four here. years of continuous air sampling neighbor stations are theand South the African German SANAE Neumeyeron station, IV snow-free bedrock 420 station, km and 190 east-north-easttated km accessible by by of west-north-west, a air TRS. blue-ice transport TRS airfieldthe during on is Norwegian Antarctic the situated Ministry summer, glacier facili- 7 ofresearch km station north the and of Environment the provide decidedyear-around main it station. operation. to with In The a upgrade June new runway an 2003, hensive for station existing atmospheric airplanes was monitoring summer (the o program Troll was Airfield) established enabling including pollutant monitor- 2 Methods Sample location. managed from the NorwegianLand, Troll Antarctica), station located (TRS; at 72 DronningJutulsessen Maud glacier, about Land/Queen 235 Maud km south from the Antarctic coast (Fig. 1). Its closest alytical quantification method, asimportant well for as data comparability priorityincluding and target also potential POPs. for inter-hemispherical This investigation POP oftive harmonization distribution trace global is analyzes characteristics. transport of The patterns legacymonitoring POPs quantita- performed program for as the weekly firststudy. four sampling years (2007–2010) of form the the still ongoing scientific basis for this Land, Antarctica). The POP atmosphericperience monitoring with is similar building Arctic upon atmospheric longby monitoring scientific NILU programs ex- handled since and 1989. overviewed with The the atmospheric similar POP monitoring monitoringmountain at program (Ny- Troll at is the coordinated closely Arctic monitoring station on the Zeppelin toring program for selected legacy POPs at the Antarctic Troll station (Dronning Maud 5 5 25 15 20 10 25 15 20 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | http: http: ). FLEXPART -hexane). Ex- stream. Before n 2 ˚ Alesund, Svalbard, transport blanks) was + n.d.). = 3 for solvent blanks (using C and 2 min splitless time). The analyzes ◦ > ) 6226 6225 PRODUCTS/STATIONS/TROLL/ S/N To relate measured concentrations to transport from average blank value plus 3 standard deviation (STDev) of LOD are considered with high uncertainties and reported = The same priority target analytes were chosen for the Troll C labeled Internal Standards (IST) for all congener and isomer > x > 13 The responsible technicians at the Troll research station followed andreas/BACKWARD ∼ ) for thorough examinations. However, all original data are also listed in All samples LOQ Transport model calculations. The analytical procedure used for the study was accompanied by a comprehensive Quality control. After sample preparation, the eluates were quantitatively analyzed using high- Quantitative analysis. All samples were Soxhlet extracted for 12 h with n-hexane/ acetone (50 : 50, v : v). An LOQ (Table S7). All raw data are openly accessible from the NILU database ( //zardoz.nilu.no/ < //ebas.nilu.no made with the2006; Lagrangian Stohl particle et dispersion al., model 2006, FLEXPART 2007, (Kallenborn 2010) et for al., the entire measurement period (see contamination during sample processing wasevated found values for in the field data and laboratory presented(for blanks). here Based both (no upon laboratory el- average and blank field concentrations all blanks) the compounds limit with of LOQ quantificationthe (LOQ) was blank calculated concentrations. for Appendix B of thefurther Supplement statistical (Table S8). treatment (treated All as values not below detected LOD werepotential excluded from source regions, 3-hourly backward simulations from the Troll station were added to the field samplesand in transport. order to control unintended contamination during storage quality control program basedto on EU the standard requirements EN of 45001.calculating NILU’s The the accreditation, instrument signal according limit to of noisetensive detection ratio field (LOD) ( and was laboratory determined blankpossible by values contamination were analyzed during in sample order transport to and monitor and laboratory control work. No evidence for Supplement). Isotope dilution wastarget chlorinated applied chemicals. for identification and quantification ofdetailed the routines developed by NILUfieldwork. in A order set to avoid of unwanted field contamination blank during samples (1 field blank/month incl. reference and quantifier ions selected, lock mass calibration, see Appendix A, for injection and transfer line, temperature program, mass spectrometer parameters resolution gas chromatography coupledtrometer to as a detector high-resolutionPalo (HRGC/HRMS). sector Alto A CA, field 6890N USA) mass waster Agilent spec- coupled (Waters, gas to Milford, chromatograph an MA, Autospecgas (Agilent, USA). Ultima chromatograph An sector in aliquot field splitless of masswere mode spectrome- 2 performed (280 µL with of maximum theHCB, resolution DDT eluate derivatives) (ca. was and 10 injected Negative 000)respective Ion into in compounds Chemical the groups Ionization Electron (for mode Impact details NICI: on (EI: OCP) separation for PCBs, parameters the incl. temperatures harmonized with respect tocomparability of sampling the and obtained priority datageners for compounds future and in global 13 assessments. order organochlorine Inpounds to total, pesticides and 32 allow (OCP) analytical PCB good con- methods, wereplement. see quantified Appendix (for A details including on Tables S1–S3) com- of the Sup- filled with precleaned andcleaned preconditioned sodium Silica sulfate (2 %-w forto cleanup. water) 500 After and µL cleanup, a (Turbovap) and volume topquantitative of further layer analysis, the reduced of 10 eluate to ng pre- 100 was of µLrecovery reduced unlabeled standard under tetrachloronaphthalene (RecStd, a (TCN) Tables gentle S1–S3). was N added as POP monitoring as measured atArctic) the for Zeppelin the research past 20 station yr. (Ny- The respective monitoring programs (Zeppelin and Troll) were amount of 10 ng of groups analyzed was added priorplement). to The extraction GFF (for and details PUFca. extracts see were 500 Appendix µL unified A was after of performed extraction. Volume on thevolume reduction a reduction, Sup- to Turbovap the (Caliper-Zymark, extract Hopkinton, was MA, transferred USA). to After a 15 cm glass column (with stop cock) 5 5 15 20 25 10 25 15 20 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | erent congeners ff ) in the cell would 1 − ) in a particular grid cell 1 − grid, under the assumption ◦ 1 × ◦ resolution. During every 3-hour inter- ◦ . The congerers PCB 28, 33, 47 and 52 1 ) on a 1 3 (in units of skg − S × S ◦ 6228 6227 -nonachlor), as well as the six major constituents ected by significant uncertainties (Breivik et al., 2002). ff -DDT, DDE, DDD) were analyzed (see Table S6). 0 trans-, cis p , p - 0 p , o distribution in a 100 m layer adjacent to the surface (so-called footprint S LOQ – between 0.09–1.54 pgm < -chlordane and LOQ) are listed in Table 1. -hexachlorocyclohexane (HCH), four chlordane-related cyclodiene pesticides γ > The low PCB concentrations measured at Troll, relative to what has been reported As a general feature, in six samples, PCB 47 was found to be the most abundant - and trans-, cis A representative group of organochlorinealytes pesticides for (OCP) the was Troll selected monitoringare as program target target (12 an- chemicals compounds). for Allvironmental the of Proramme) global the Stockholm monitoring here convention selected planα for OCP of the global the regulation UNEP( of (United POPs. Nations The En- of the DDT group ( although these numbers are a For comparison, thefound compound in specific Appendix A limit of of the Supplement quantification (Table S7). (LOQ)3.3 values can Chlorinated be pesticides were found in all sevenlevels samples ( above LOQ. The seven samples with quantified PCB for the Arctic (Breivik ethistorical al., use 2002), of could PCBs beinventory took expected of as place global only in PCB anChile the production estimated and Southern 3 and Argentina, % Hemisphere the use of estimated according (Hungrespectively, the historical which to et use translates a al., of into global total 2010). 0.1 PCBs For % is the and 1270 countries 0.5 and % 7200 of of tons, the global historical production, possible local contamination is assumed. Therefore,remote the station location will for be the moved to next2013). a sampling more season (C. R. Lunder, personal communication, congener ( pattern elucidation for PCBs was performed in this study. Based upon this information, due to elevated blank levelstions measured below (Table S7), the for limit most of of quantification the samples (LOQ) concentra- were determined. Therefore, no in-depth HCB was identified as the most abundant target3.2 contaminant in this study. Polychlorinated biphenyls (PCB) PCB (CAS No. 1336-36-3) iswith a 1 technical to mixture 10 consisting chlorineused of atoms in 209 attached a di to variety a ofcongeners biphenyl technical analyzed, molecular applications only structure. (Breivik 14 PCB congeners etary has were al., 2008 been quantified 2002). and in Of September 7 the 2007. samples total Although between of PCBs Febru- 32 were PCB identified in all Troll air samples, 3.1 Hexachlorobenzene (HCB) Hexachlorobenzene (HCB; CAS No. 118-74-1)is was predominantly released used as as an fungicide. industrial by-product Currently from HCB various chemical processes. mixing ratio at theproduce. receptor The that alayer) source was used of to unit characterizetential strength the POP (1 potential surface kgs influence sources during from theperiod. Southern 20-days Hemisphere For preceding po- the the 3-hourly particle purposewhen release POP of samples were this taken. paper, model results were averaged3 for the periods Results and discussions Medium-Range Weather Forecasts with 1 val, 60 000 particles werefor 20 released days at to the calculatethat emission measurement sensitivity removal point ( processes and can followed beis backward neglected. proportional to the particle residence time in that cell and measures the simulated was driven with 3-hourly operational meteorological data from the European Centre for 5 5 25 15 20 10 25 20 15 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | - ) 0 3 p − , Sum p -DDT -DDT -DDE -HCH 0 0 0 > γ p p p / , , , − o p p -HCH had -HCH with α HCH in the α α − γ / C based on pre- − ◦ Sum PCB α > -DDT and 50 -HCH and 0 a − C) previously reported p , ◦ p -HCH isomer was identi- -DDT in air samples may -HCH isomer ( 40 α p C as detailed in Appendix C to γ ◦ , − ◦ -HCH was usually 3–4 times o -CD) was the most abundant 5 α 50 Sum HCH + − cis . The C to > ◦ 3 − 0 ∼ C to ◦ C), according to Hansen et al. (2009). ◦ -HCH. Thus a ratio γ ). Surprisingly, the presence of 40 3 − − -chlordane ( ‘-DDT is present with 15–20 % dependent on 6230 6229 p , cis ective in winter than in summer (Gambaro et al., o C to ff (average concentration) for the entire monitoring ◦ 3 0 -DDT ratios between 1 and 6 could be established, − 0 ∼ p , o ‘-DDT and p , -DDT/ 0 p p , p -DDE higher concentration levels were found (identified in 156 sam- 0 -DDT) indicates fresh, not weathered technical DDT as potential source p 0 , -DDT (the major byproduct) is about 3–5. Thus, a ratio between 1 and 3 0 p p , p , o o -DDT was confirmed in about 30 % of all samples. In the technical DDT mixture 0 Sum chlordanes). For single compounds other than HCB, p , > -DDT/ o 0 p The long-range atmospheric transport potential among the individual compounds For both DDT-group (dichlorodiphenyltrichloroethane derivatives) and cyclodiene The most abundant OCP compound in Troll atmospheric samples was HCB was identified as the major POP in the Antarctic air samples with concentra- , p viously reported data from Troll ( ples (mainly for 2007,were see detected Fig. only 3). occasionally. In the period 2008–2010, selected may be furtherrain discriminated and by snow their (Lei potential andsorbed to Wania, onto be 2004). aerosols scavenged To illustrate, by forC, we aerosols, selected which have POPs covers estimated the from the observed 5 percentage temperatureat range Troll ( (Hansen et al.,centage sorbed 2009). onto To illustrate aerosols this, for we selected have POPs evaluated from the estimated per- for the observed airby-product during contamination. dicofol However, production, since aalso DDT high indicate proportion is dicofol of application considered in anples, the in important respective 35 source samples regions.confirming For the a Troll contribution air of sam- fresh technical DDT/dicofol in the respective Troll air sam- of those compounds (identified inwhereas 162 samples, for concentation levels: 0.02–0.20 pgmples; concentration levels: 0.02–0.42 pgmand the major constituent is the production pathways (Metcalf, 1995). TheDDT ratio and between the major constituent ( air masses. Variations between 2ples. and 5 were commonly observed in the Troll airpesticides sam- (chlordane related compounds)air samples. very The low chlordane levels compound were detected in the Troll range of 3–5 is considered as an expected ratio indicating no unusually contaminated higher concentrated than the sister isomer, and, thus, lower HCB air concentrationstrations during found the at summer Troll station season.Zeppelin The are station HCB generally concen- (Svalbard, 3–4 times Norwegian Arctic). lower than those observed atconcentrations the varying between 0.02 andfied 0.46 in pgm all 196 samples2009; analyzed. As Hung also et shown for al.,higher the concentrations 2010; Arctic in Zeppelin Kallenborn station Troll air (AMAP; ratio: and 2–24) samples Berg, in than all 2006; the Troll air Ma related samples. For et the HCH al., isomers, 2011), winter period (week 25–45) andis lower likely levels related during to the summer seasonallySouth seasons America, varying which (Fig. atmospheric is 2). transport much This more from2005; e Kallenborn Australia, Africa et and al., 1998).bination However, with increased higher OH-radical concentrations ambient in temperatures com- may also lead to increased transformation DDT were the most prominent constituents. tion levels varying around 22period. pgm HCB was positively identifiedcould be in established all for HCB 196 at samplestrast Troll during quantified. to the No 4 the yr temporal measuring Arctic trend seasonal period. data However, pattern in from con- was the found for Zeppelin Troll station air (Hung samples et with highest al., levels 2010), during a the characteristic austral Although considerable concentration variationsseveral were features identified were for the foundspheric entire characteristic samples. data for HCB set, the wassums POP the of distribution POP with in HCHs, the the PCBs, highest Troll DDTs concentrations, atmo- and followed by chlordanes the (HCB 4 Discussions 5 5 25 15 20 10 25 15 20 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | - 0 > ( p , ® p erences ff -DDD, 60 % of -HCH (Lei and 0 α p -HCH concentra- , γ p -HCH were observed γ erences in rain or snow ff erences in atmospheric de- -HCH is found in concentra- ff γ C, 87 % of ◦ 15 − erences predicted within groups of ff whereas 3 − -HCH are found for samples taken during erent emission sources, the concentrations γ ff 6232 6231 . An unusually high concentration of at least one of 3 − erences in snow scavenging between these two isomers ff -HCH) were plotted against the concentrations of an in- -DDE is predicted to be sorbed onto aerosols which could γ 0 p , -DDE appears to be occasionally elevated at Troll. Thus, 0 p p , p -HCH may be more easily washed out by rain than γ cult to predict (Lei and Wania, 2004). For the one-week sampling period ffi -HCH (Fig. 4), and for several of those enhanced transport from continental C, HCB, HCHs and PCBs 28, 52 and 101 are predicted to dominate in the ◦ γ -HCH) as well as the technical HCH mixture was produced in South Africa in γ 20 -DDT and 29 % of 0 − p Also several other samples were identified with elevated contribution of either HCB In Fig. 4, significantly elevated levels for the agrochemical Figure 5 shows the corresponding footprint emission sensitivity obtained from the For HCHs direct applications of technical HCH or emissions from technical HCH For other related substances which were predominantly present in the gas phase al- , significant amounts. It isare also still reported stored that and/or deposited about in 70 000 this country. tons ofand/or HCH waste isomers source regions (mainly fromtions. South Thus, the America) atmospheric can long-rangeas be transport the of seen main polluted in source air the for masses the FLEXPART is legacy calcula- considered POPs monitored at Troll. Southern Africa is nearlyindicating one much order stronger of transportthe magnitude from increase Southern higher in Africa than emission to sensitivity intion is Troll the than consistent enhancement. seasonal normally. with According Again, mean, the to measured 99 a % recent review by Vijgen et al. (2011), Lindane FLEXPART 20-day backward simulation for theThe period emission when this sensitivity air over sample Chileby was and nearly taken. Argentina an for order thisfootprint sample of emission (Fig. sensitivity, magnitude indicating 5) compared unusually issource strong to enhanced transport regions the to from seasonal-mean the these Troll 20-day-backwards potential station. during week 27/2009. For thission week, sensitivity the FLEXPART values calculations extend showfor much that seasonally high further emis- averaged north transport over (upper Africa (lower part, part, Fig. Fig. 5). 5) The than emission sensitivity over tions of around 0.1the to compounds 0.5 indicates pgm atmosphericstation. transport Relatively of high contaminated concentrations airweek mass of 27/2009 to and 33/2010 the (Fig. Troll 4). dustrial chemical (HCB), see Fig.samples 4. with HCB levels is between the 10 most and abundant 80 contaminant pgm in Troll air waste deposited in southern Africantribute or to South the American observed regions elevated may levels. also directly con- 4.1 Atmospheric long-range transport For the elucidation of potentialwere contamination compared. sources, also For the general pattern identificationof of di di a typical agrochemical ( at Troll the measured airTherefore concentrations one are may often argue veryare low that or any best close potential identified to long-range by detectionsamples atmospheric limits. showing elevated transport occasionally air events elevated concentrationsalone air of may concentrations rather more of indicate less volatile influence of volatile substances, local substances while sources within the Antarctic. DDE is associated more toto the be vapour phase, deposited whereas more the rapidly other by isomers particle are related expected depositionmost processes. through the entire temperaturescavenging range, may such be as more HCHs, relevantposition. to di elucidate While potential di Wania, 2004), any potential di are more di gaseous state among the substancesmeasurements. included, There which mirrors are the alsosubstances overall results in some of terms notable the of di gas/particlep partitioning. At help to explain why At 5 5 25 15 20 10 25 15 20 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | -HCH γ ectiveness as- ff -HCH) in Asian coun- γ 99 % > orts for the continuous surveillance of ff -HCH deposited in South Africa previously γ 6234 6233 erences in available monitoring infrastructure, cost ff -HCH was the most abundant HCH isomer analyzed in all samples. α -HCH was identified in atmospheric samples. However, in the data set γ In order to gain scientific understanding on global distribution processes for anthro- In the early studies (sampling 1993, 1995; Kallenborn et al., 1995, 1998) a slight pre- large lack of atmospheric POPpecially monitoring in data from Antarctica the (compared Southern tomonitoring Hemisphere Arctic and regions). and es- Therefore, research the study heretribute presented on significantly POP to POP the distribution ongoing inpriority coordinated e Antarctic POPs in air Antarctica, will anding hopefully thus, to con- help the to currently understand observed the global complex distribution processes of lead- this type of anthropogenic pollution. sphere. The long-term POPs monitoringon networks the in same Southern levels Hemisphere of aregions (UNEP,2009). not sophistication The yet as obvious compared di to/withfor networks establishing in and the maintaining northernprograms the and re- infrastructure, research expert funding support, priorities is national considered regulation as important reason for the still pogenic pollutants, the establishmentconsidered of an important a tool global2009; both atmospheric Kallenborn for monitoring and regulators Berg, network andmonitoring 2004; environmental is programs Kallenborn scientists are (AMAP, et encouraged al.,to to 2012). establish coordinate Therefore global their regional networks monitoring based sessment (UNEP, priorities 2009). of the However, in POPs the order Stockholm first conventions revealedmonitoring global that data most e of (relevant atmospheric for POPs regulative purposes) is reported from the Northern Hemi- Table 2) may be soughttries in (i.e. the China and national India) ban aroundcontribute of the (incl. year lindane increased 2000. ( emissions However, other from potentialmentioned) reasons and may should thus besources included for Antarctic in atmospheric the samples. current discussion on potential tion reductions of about a factor 100 compared to the 1993 and 1995 campaigns (see The most obvious reason for this pattern shift along with significant overall concentra- 1993 sampling campaign atThe Terra-Nova-Bay average (Victoria levels Land; measured in Kallenbornare Terra-Nova-Bay air et based from al., on 2003 1995). nine (Cincinellitor et weekly of al., 2 summer 2009) lower samples concentrationscompared only is, to the thus, (December 2010 considered to whole-year as sampling Marchvariation well set with 2003). within from a Troll, the A given summer the range minimum fac- observed of (Fig. seasonal variations 2). dominance of presented here, Terra-Nova Bay air samples was recentlydiscussed results published are (Gambaro summarized et for al., comparisonanalyzed, in 2005). considerable Table The concentration 2. reductions For here- almost are all registeredmentioned compounds compared previous to atmospheric the POP above measurement campaigns.HCB The (Table only 2) exception is for which similar concentration levels were found as registered in the 1995). As a follow upAntarctic of the Survey 1993 (BAS), sampling NILU programPOPs and performed in in a cooperation Antarctic first with air the year-aroundlands) at British measuring in the the campaign British period for research 1994–1995ilar station (Kallenborn priority in et compounds Signy al., were Island 1998).in quantified (South During this and Orkney both paper. HCB Is- campaigns analytical and sim- methodsexchange HCHs were of were used selected also chlorinated as measured during pesticides studied in a in 2003 process the (9 study samples; Ross Cincinelli for Sea et air/water region al., at 2009). Terra Finally, a Nova campaign-based Bay study on PCBs in Previously, only ations few were collected campaign-based with active dataweeks high-volume sampling sampling sets devices campaign in of was Antarctica.Research performed atmospheric An station in now eleven Terra-Nova-Bay, Zuchelli POP 1993 station (October–December) (Victoria concentra- at Land; Kallenborn the et Italian al., 4.2 Comparison with historical data 5 5 25 15 20 10 25 15 20 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | 83 pp., + 6236 6235 . This work was financed through the Norwegian Climate and Pollution mospheric PCB concentrations9406–9411, at 2005. Terra Nova Bay, Antarctica, Environ. Sci.Stebel, K., Technol., Schmidbauer, 39, N., Solberg, S., Wasseng, J. H., and Yttri, K. E.: Atmospheric mon- air-water flux of organochlorineSci. pesticides Technol., 39, along 465–470, 2005. the western Antarctic peninsula,sistent Environ. organic pollution. Air Pollutionof Studies Air No. Pollution acting 19. within TaskAir Force the Pollution, on framework 256 of Hemispheric pp., the Transport 2010. Convention on Long-range Transboundary rules for agricultural biotechnology and chemicals, Environ. Politics, 12, 1–23, 2003. inventory for selected PCB congenersconsumption, – Sci. a Total Environ., mass 290, balance 181–198, approach 2002. 1 Global productionDickhut, and R. M.: Organochlorinethe pesticide Ross air-water Sea, exchange Environ. and Poll., bioconcentration 157, in 2153–2158, krill 2009. in characteristic travel distance, Environ. Sci. Technol., 37, 766–771, 2003. 2009. rzeniowski, S. H.: Modelling global-scalerect sources, and Environ. transport Sci. of Technol. perfluorooctanoate 40, 6969–6975, emitted 2006. for di- tive Programme for monitoringEMEP/CCC-report 4, of 115 the pp., 2008. Long-range transmission of air pollution in Europe, Hansen, G., Aspmo, K., Berg, T., Edvardsen, K., Fiebig, M., Kallenborn, R., Lunder, C. R., Gambaro, A., Manodori, L., Zangrando, R., Cincinelli, A., Capodaglio, G., and Cescon, P.: At- Dutchak, S. and Zuber, A. (Eds.): Hemispherical transport of air pollution 2010. Part C: Per- Dickhut, R. M., Cincinelli, A., Cochran, M., and Ducklow, H. W.: Atmospheric concentrations and Clapp, J.: Transnational corporate interests and global environmental governance: negotiating Cincinelli, A., Martinelli, T., Del Bubba, M., Lepri, L., Corsolini, S., Borghesi, N., King, M. D., and Breivik, K., Sweetman, A., Pacyna, J. M., and Jones, K. C.: Towards a global historical emission Beyer, A., Wania, F., Gouin, T., Mackay, D., and Matthies, M.: Temperature dependence of the Armitage, J., Cousins, I., Buck, R. C., Prevedouros, K., Russel, M. H., MacLeod, M., and Ko- AMAP: Arctic Pollution 2009, Arctic Monitoring and Assessment Programme, Oslo, xi ACIA: Arctic Climate Impact Assessment, Cambridge University Press, 1042 pp., 2005. Aas, W. and Breivik, K.: Heavy metals and POP measurements 2006. EMEP Coopera- References acpd-13-6219-2013-supplement.pdf nation of remoteness andBy lack combining of modern potential modelling localtion tools sources data, with for several pattern Antarctic atmosphericcussed evaluation sampling here. of long sites. The available influence range of concentra- theorganochlorine transport southern pesticides events African (i.e. continent HCHs) were for was the identified confirmed transport in and of this legacy dis- study. Supplementary material related to thishttp://www.atmos-chem-phys-discuss.net/13/6219/2013/ article is available online at: Acknowledgements. Agency (KLIF). Financial support fromwas the also Norwegian received. Antarctic FLEXPART Research modellingin Expeditions the was (NARE) framework supported of byPolar the the CLIMSLIP institute Research project. (NPI) Council We atcompetent of thank sampling Norway the the storage year of Antarctic around theNILU Troll exposed crews samples laboratory. station of as The the for well NILU as Norwegian maintaining laboratoryration for team shipping the and the has analytical sampling samples performed procedures to unitsultra-trace well the according analysis under and to at rigorous the comprehensive the sample qualitySynnøve prepa- institute. control G. Thanks requirements Trandem to for for Hansteam, quantitative Gundersen, but analysis Anders especially and R. Jan the Borgenthe H. work Troll as station Wasseng in well and is as the calibration thanked of laboratory. for sampling The annual units. NILU maintenance field of the equipment at The first long-term monitoring programpollutants for is atmospheric presented. transported The persistentNorwegian organic monitoring Troll program station has (Dronningsiderably been Maud lower established than Land). (2007) the The monitoring at concentrations data the found measured were in the con- Arctic illustrating the combi- 5 Conclusions 5 5 30 25 20 15 10 10 15 20 25 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | erences in Arctic and , 2010. ff cient scavenger of organic chemicals?, ffi 10.1029/2009JD012536 6238 6237 Convegno Nazionale, Contaminazione Ambientale, ◦ , 2004. , 2005. er, A., and Weber, R.: Hexachlorocyclohexane (HCH) as new Stockholm ff 10.5194/acp-4-2337-2004 10.5194/acp-5-2461-2005 fate in the environment, Environ. Poll., 100, 223–240, 1999. Chem., 17, 2148–2158, 1998. Tian, C. G., Scha Convention POPs-a global perspectivemers, on Environ. Sci. the Pollut. management Res., 18, of 152–162, Lindane 2011. andaccumulation its in waste polar regions, iso- Environ. Sci. Technol., 37, 1344–1351, 2003. Western European and other groups (region), 106 pp., 2009. group, 65 pp., 2011. 4245–4264, 1998. port, Western Europe and Othergramme, Groups 105 (WEOG) pp., Region, 2008. United Nations Environment Pro- Atmos. Environ., 38, 3557–3571, 2004. in the self-cleansingdoi: capacity of the troposphere,in Atmos. the Arctic Chem. induced Phys., by climate 4, change, Nature 2337–2344, Climate Change, 1, 255–260, 2011. ganic pollutants: techniques tonegotiations, provide Environ. the Sci. scientific Technol., 33, basis 3482–3488, for 1999. POPs criteriasphere, in J. international Geophys. Res., 115, D02305, doi: particle dispersion modeldoi: FLEXPART version 6.2, Atmos. Chem.model FLEXPART Phys., against 5, large scale 2461-2474, tracer experiment data, Atmos. Environ., 32, 1998, organic pollutants as an589–493, important 2012. tool for scientific risk assessment, Atmos. Poll. Res., 3, air and seawater from the Arctic to Antarctica, Environ. Sci. Technol., 44, 8977–8982, 2011. port of persistent organic9/10, pollutants 1082–1091, (POPs) 2006. to Bjørnøya (Bear island), J. Environ. Monitor., ogy, Vol. 14, edited by: Kroschwitz,524–602, J. and 1997. Howe-Gant, M., NY: John Wiley & Sons, New York, Antarctic air samples: distributionAntarctic Air, of in: persistent Proceedings, Atti andUniversita del Ca’ high Foscari 4 di volatile Venezia, Programma compounds Nazionale in di Ricerche Arctic in Antartide,1–8, and levels 1995. and atmospheric long-rangeAntarctica, transport Sci. Tot. of Environ., persistent 220, 167–180, organochlorines 1998. to Signy island, painen, S., Stern, G., Sverko,pollutants E., in Fellin, P., and the Skov,1993–2006, H.: arctic Sci. Atmospheric under Tot. monitoring Environ., the of 408, 2854–2873, organic arctic 2010. monitoring andof assessment airborne programme transport (AMAP): processesPeople in into a Changing Polar Environment, Regions, editedHegseth, by: in: E., Ørbæk, Falk-Petersen, Arctic J. 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D., Schlabach, M., and Harris J.: Ambient air Kallenborn, R., Oehme, M., and Schmidbauer, N.: Similarities and di Kallenborn, R. and Berg, T.: Long-term atmospheric contaminant monitoring for the elucidation Hung, H., Kallenborn, R., Breivik, K., Manø, S., Brorstrøm-Lunden, E., Olafsdottir, K., Lep- Holoubek, I., Ansorgova, A., Shatalov, V., Dutchak, S., and Kohoutek, J.: Regional background 5 5 30 25 20 15 30 25 10 20 15 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | LOQ LOQ LOQ LOQ LOQ LOQ < < < < < < LOQ LOQ LOQ < < < LOQ 0.07 LOQ 0.04 LOQ LOQ LOQ < < < < < ] 3 − LOQ LOQ LOQ LOQ LOQ < < < < < LOQ 0.21 0.19 0.48 LOQ LOQ LOQ LOQ LOQ < < < < < < 6240 6239 LOQ LOQLOQ 0.10 0.07 0.07 0.24 0.09 < < < , 2011a. LOQ 0.14 0.29 0.80 0.56 1.54 0.47 LOQ LOQ 30/08 48/08 10/09 21/09 28//10 32/10 37/10 < < < ¨ oller, A., Sturm, R., and Ebinghaus, R.: Transport and fate of hex- ]. 3 -PentaCB 101 -PentaCB 105 − 0 0 10.5194/bg-8-2621-2011 -TetraCB 47 -TetraCB-TetraCB 52 66 0.18 0.04 0.17 0.03 0.15 0.22 0.19 0.45 0.17 ,5-PentaCB 99 0.11 0.04 0 0 0 0 ,5-PentaCB 114 0.02 0.02 0 ¨ -TriCB-TriCB 28 0.25 37 0.16 0.04 0.13 0.02 0.21 0.01 0.18 0.02 0.45 0.01 0.15 0.06 0.02 ,5-TetraCB 74 0.03 ,4,4 oller, A., Ahrens, L., Sturm, R., and Ebinghaus, R.: Brominated flame retardants in 0 0 0 0 PCB concentrations in Troll air samples (2007–2010). The concentration levels are ,5-TriCB,4,4 31 0.23 0.22 ,5,5 ,4,4 ,4,4 ,4,5,5 0 0 0 0 0 0 ,3,4-TriCB 33 0.18 0.11 0.10 0.15 0.13 0.35 0.11 0 2,4,4 2,4 2 3,4,4 2,2 Structure PCB Sampling week/year conc. [pgm 2,2 2,3 2,4,4 2,2 2,2 2,3,3 2,3,4,4 seawater and atmosphere of45/5, the 1820–1826, Atlantic 2011b. and the southern Ocean., Environ. Sci. Technol., achlorocyclohexanes in the2633, oceanic doi: air and surface seawater, Biogeosciences, 8, 2621- Table 1. given in [pgm Xie, Z., M Xie, Z., Koch, B. P., M 5 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper |

18 0.5 0.2 22.9

(this study) 17 4 d 24 stations stations are shown. (average conc.) . For comparison the British 18 not detected; = Troll Troll Atmopsheric observatory (Norwegian Troll 6242 6241 (average conc.)

– 0.2 (0.07–0.4) – 0.03 9 (n.d.–15) 7 (0.02–17) 0.7 (0.3–1.3) 3.5 (n.d.–6) 0.4 (.004–0.9) – 0.1 position position of the Antarctic – DDT, DDD, DDE, 0 p ,

o research research Station, dronning Maud Land, Antarctica) research stations Signy Island and the Italian Terra Nova of Courtesy Map: Wikipedia Bay / 0 -HCH 13 (5–20) 27 (3-33) 0.8 (0.3–1.2) p – chlordane and nonachlor; , γ URES and TABLESURES and b p a c = Atmospheric POP distribution in Antarctic air; a comparison (concentration range in

Figure Figure 1: The FIG Figures ] (average conc.) The position of the Antarctic Troll Atmopsheric observatory (Norwegian Troll research - and 3 − α trans/cis

3 4 5 6 7 8 9 1 2 10 11 12 Compounds[pgm HCB Terra NovaSum Bay; 1993Sum 4 Signy CD Island; 1994–1995Sum 6 DDT Terra-Nova-Bay; 2005Sum PCB Troll; 2010 21 (n.d.–28) – 11.4 (6–20)2 Only gas phase compounds quantiﬁed Sum Sum DDT SUM PCB, 18, 28/31, 52, 99, 101, 118, 149, 138, 153, 180; n.d. Fig. 1. Station, dronning Maud Land,Island Antarctica). and For the comparison Italian the Terra Nova British Bay research stations stations are shown. Signy Map: courtesy of Wikipedia. c d a Table 2. b parenthesis).

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Figure 3: Figure 2: Concentration distribution of hexachlorobenzene (HCB) in atmospheric samples Concentration distribution of hexachlorobenzene (HCB) in atmospheric samples from p 35 30 25 20 15 10

Figure Figure 3: Figure 2: Concentration distribution of hexachlorobenzene (HCB) in atmospheric samples

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Fig. 3. station (Antarctica) ; y-axis Troll (Antarctica), period: 2007–2010, x-axis: sample weeks, y-axis: conc. [pgm Fig. 2. 9 7 8 2 3 4 5 6 1 10

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ncentration comparison of HCB comparison (y ncentration Troll (Antarctica: 2007 (Antarctica: Troll ncentration comparison of HCB comparison (y ncentration Troll (Antarctica: 2007 (Antarctica: Troll onthly onthly simulations (June and August) for the entire sampling period (2007

Figure 5: Footprint emission sensitivities calculated with FLEXPART. m examples for the transport climatology for backward simulations the for respective two months. weekly POP samples (right) 33/2010. and (left) 27/2009 taken at Troll station during weeks

Figure 4: Co 4: Figure Concentration comparison of HCB (y-axis) and Footprint emission sensitivities calculated with Upper FLEXPART. line: average monthly

8 9 1 2 3 4 5 6 7 14 15 16 17 18 19 10 11 12 13 onthly onthly simulations (June and August) for the entire sampling period (2007

Fig. 5. simulations (June and August) fortransport the climatology entire sampling for period thetwo (2007–2010) weekly respective as POP months. examples samples for Lower taken the at line: Troll 20-day station during backward weeks simulations 27/2009 for (left) and 33/2010 (right). Fig. 4. (Antarctica: 2007–2010).

27/2009 (left) and 33/2010. (right) 33/2010. and (left) 27/2009 Figure 5: Footprint emission sensitivities calculated with FLEXPART. m examples for the transport climatology for backward simulations the for respective two months. weekly POP samples taken at Troll station during weeks

Figure 4: Co 4: Figure

9 8 2 3 4 5 6 7 1 14 15 16 17 18 19 13 10 11 12