ARTICLE IN PRESS AE International – Europe Atmospheric Environment 38 (2004) 5013–5023 www.elsevier.com/locate/atmosenv Atmospheric speciation of ionic organotin, organolead and organomercurycompounds in NE Bavaria (Germany) Jen-How Huanga,Ã, Otto Klemmb aDepartment of Soil Ecology, Bayreuth Institute for Terrestrial Ecosystem Research (BITO¨K), Dr. Hans-Frisch-Str. 1-3, University of Bayreuth, D-95440 Bayreuth, Germany bInstitute for Landscape Ecology, Climatology, University of Mu¨nster, Robert-Koch-Str. 26, D-48149 Mu¨nster, Germany Received 1 October 2003; received in revised form 29 April 2004; accepted 14 June 2004 Abstract Organotin (OTC), organolead (OLC) and organomercury(OMC) compounds are highlytoxic and exhibit a potential negative effect on terrestrial ecosystems. Individual ionic OTC, OLC and OMC compounds were identified and their concentrations determined in the gas phase, aerosol particles, and bulk precipitation at a rural (Waldstein) and an urban (Bayreuth city) site in NE-Bavaria. At both sites, butyltins, methyltins, octyltins, trimethyllead and monomethylmercury concentrations in the gas phase were o100 pg mÀ3 (determined as corresponding Sn, Pb and Hg concentrations, respectively) with the dominance of tri- and di-substituted OTC and octyltins. The same species were found in bulk precipitation with concentrations o25 ng lÀ1 (Sn, Pb, Hg) with the dominance of mono-substituted OTC. In aerosols, only butyltins, dimethyltin and monomethyltin (o500 pg Sn mÀ3) were found and mono-substituted OTC predominated. No significant difference of concentrations of organometallic compounds in the atmosphere at the two sites was found. For OTC, the washout factors was in the order: mono-Xdi-4tri-substituted OTC, and the gas/ particle partition coefficients were mono-bdi-btri-substituted OTC. The distribution spectrum of OTC in aerosols showed the strong linkage of OTC to the long-lived particles and high accumulation of OTC in the filter at the Waldstein site. The results indicate that long-range-transport of organometallic compounds in the atmosphere is an important source at our both sites. Aerosol particles mayserve as a sink in the chemical cyclesof OTC in the atmosphere, especially for monomethyltin and monobutyltin. r 2004 Elsevier Ltd. All rights reserved. Keywords: Ionic organotin; Trimethyllead; Monomethylmercury; Gas; Aerosol; Bulk precipitation; Waldstein; Bayreuth 1. Introduction derivatives in commercial use than anyother element. This gave rise to a dramatic increase in the worldwide Organotin (OTC), -lead (OLC) and -mercurycom- production of OTC from less than 5000 tons in 1955 up pounds (OMC) are highlytoxic organometallics in the to 50 000 ton in 1992 (Hoch, 2001). Leaching from soils environment. Tin has a larger number of organometallic and landfills (Mersiowskyet al., 2001 ), weathering of plastics (Quevauviller and Donard, 1991), and dissolu- ÃCorresponding author. Tel.: +49-921-55-57-61; fax: +49- tion of ship paintings (Batley, 1996) lead to the release of 921-55-57-99. these compounds into aquatic systems. Sediments of E-mail address: [email protected] rivers, estuaries and marine systems have been identified (J.-H. Huang). as the major environmental sinks of OTC. As a 1352-2310/$ - see front matter r 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.atmosenv.2004.06.015 ARTICLE IN PRESS 5014 J.-H. Huang, O. Klemm / Atmospheric Environment 38 (2004) 5013–5023 consequence, there is abundant literature on input, the atmosphere (Lin and Pehkonen, 1999; Radojevic distribution and toxicityof OTC mainlyfocused on the and Harrison, 1987). Besides, peralkylated OTC, OLC aquatic environment (Hoch, 2001). Current studies and OMC are almost insoluble in the water, but ionic indicated that OTC can be re-emitted from the marine species are water soluble and quite stable (Hempel et al., environment to the atmosphere bytransformation of 2000). Therefore, ionic OTC, OLC and OMC may ionic OTC into volatile species (Amouroux et al., 2000), distribute more widelyin the environment than their and atmospheric transport and deposition was recog- peralkylated forms and thus exhibit a higher potential to nized as source of OTC in the terrestrial ecosystems affect vegetation, fauna and humans. Ionic OTC, OLC (Huang et al., 2004). and OMC in the atmosphere were recognized as an Peralkylated organolead compounds like tetramethyl- important source of these organometallic compounds in lead and tetraethyllead have been used as antiknock forest soils. However, information about their source, additives in gasoline products for several decades distribution and behavior in the atmosphere is little, (Łobin˜ ski et al., 1994). Lead-containing antiknock particularlyin the case of OTC. The goal of this studyis additives have been terminated for several years in to gain insight into the distribution and dynamics of Central Europe and are still used in manycountries of OTC, OLC and OMC in the atmosphere, in particular Eastern Europe. In regions of high traffic densitylike to understand their gas phase/particle phase distribu- Central Europe, past emissions of OLC during several tions at an urban and a remote site, and to assess decades have led to widespread inputs of OLC in urban the potential risk of OTC, OLC and OMC in the as well as rural areas (Łobin˜ ski et al., 1994) and even in atmosphere. high altitude alpine regions (Heisterkamp et al., 1999). A recent studydemonstrated the occurrence of OLC in the forest ecosystem, even the use of gasoline with 2. Materials and methods lead had been banned for years in Germany (Huang and Matzner, 2004). Long-range atmospheric transport and 2.1. Site description deposition of OLC were supposed as the main source of OLC in the forest soils. The investigation was carried out at the ‘‘Waldstein’’ Mercuryis released into the environment byboth site in the ‘‘Lehstenbach’’ catchment in the German natural source and human activities. Due to its Fichtelgebirge mountains, located at an elevation of physicochemical properties, mercury is a widespread 765 m a.s.l. at 50 090 N; 11 520 E(Fig. 1). Mean annual element on the global scale and has to be considered as air temperature is 5.3 1C, and mean annual precipitation ubiquitous pollutant today. Human activities like is 1156 mm (1961–1990 composite, Foken, 2003). The combustion of fossil fuels, artisanal gold mining (Nriagu site is dominated byNorwayspruce ( Picea abies [L.] and Wong, 1998) and several industrial, chemical and Karst.) stands of different age. The Fichtelgebirge is pharmaceutical application of mercuryhave signifi- cantlyincreased atmospheric mercuryemissions. Con- sequently, elevated input fluxes and pools of mercury S Hof a have been found in several environments (Allan, 1999). xo n i Especially, high amounts of the highly toxic species BITÖK research site: a monomethylmercury (MMM) in predatory organisms of 'Lehstenbach' watershed aquatic food webs have been reported even in remote Rehau areas (Wagemann et al., 1998). Research on the biogeochemistryof methylmercuryhasmainlybeen N Selb focused on the formation and degradation and transport Czech Republic pathwayin terrestrial and aquatic ecosystem.Consider- Weissenstadt able progress has been made in understanding the Fich tel - relevance of mercury cycling and methylation processes in terrestrial and aquatic ecosystems (Gilmour and Marktredwitz Henry, 1991). The potential importance of atmospheric gebirge deposition of MMM as a source to aquatic ecosystems Bayreuth was confirmed byextensive field measurement and mass y n a balance calculation (Munthe et al., 1995). 0 10 20 km rm e Once OTC, OLC and OMC enter the atmosphere, G theymayjoin the cycleof water, especiallyionic OTC, B a v a r i a OLC and OMC. Peralkylated OTC, OLC and OMC in the atmosphere are not likelyto be extensivelyrecycled Fig. 1. Location of Lehstenbach catchment and Bayreuth city owing to their rapid decomposition and short lifetime in in NE-Bavaria, Germany. ARTICLE IN PRESS J.-H. Huang, O. Klemm / Atmospheric Environment 38 (2004) 5013–5023 5015 remote continental site of Central Europe, exhibiting 2.4. Gas sampling relativelylow concentrations of primaryair pollutants (Klemm, 2004). Air pollutant concentrations and Gas-phase organometallic compounds were sampled deposition of pollutants through fog deposition are bybubbling filtered (0 :45 mm) air at 1 l minÀ1 into two enhanced when the winds are from the East, i.e. from bubblers (with 100 glass volumetric flasks) in series. the more industrialized regions of eastern central Each bubbler contained 80 ml of double-deionized water Europe (Klemm and Lange, 1999; Thalmann et al., and was shielded with aluminum foliage against sun- 2002). light. A gas volume meter was installed after each Bayreuth is a city with 73 000 inhabitants, about bubbler series to measure the sampled gas volume. After 35 km to the Southwest from the Waldstein site. It is sampling, the concentrations of organometallic com- home to a universityand small- and medium-sized pounds in two bubblers were directlyanalyzedin the industries, as well as a local administration center. It lies volumetric flask with the procedures described in in the valleyof the Red Main River. Road traffic, which Section 2.7. Each gas sampling time length was between is the dominant source of air pollution, is most dense on 2 and 4 days. The sampling period was from end April a traffic circle surrounding the citycenter. The to mid May2003 at the Waldstein, and from mid May ‘‘Luitpoldplatz’’ is the intersection with