8.1.1 Long-range Transport of Atmospheric 

 Organochlorine Pollutants and Air-Sea 

 Exchange of Hexachlorocyclohexane 



DANIEL A. HINCKLEY' , TERRY F. BIDLEMAN* , and CLIFFORD P. RICE* 



^EA Engineering, Science and Technology, Sparks. Maryland, USA 



^Department of Chemistry. University of South Carolina. Columbia. South Carolina. USA 



*US Fish and Wildlife Senice. Patuxent Wildlife Research Center. Laurel. Maiyland, USA 



Introduction 



Recent evidence implicates long-range atmospheric 

 transport and deposition of organochlorine contaminants (OC) 

 to Arctic ecosystems ( Hargrave et al. ,1988; Pacyna & Oehme, 

 1988: Gregor & Gummer, 1989; Patton et al.. 1989). As a 

 result, these contaminants have been found in arctic fish, 

 marine mammals, birds, and plankton (Andersson £'/<;/., 1988; 

 Kawano et al.. 1988; Muir et al., 1988. 1990a,b; Norstrom 

 etal.. 1988). This raises concern because there are few species 

 in the polar food chain, and arctic animals are able to 

 bioconcentrate many of these hydrophobic pollutants due to 

 their high lipid content. Muir et al. (1990a,b) found that 

 atmospheric deposition of OC and subsequent bioconcentration 

 may lead to high concentrations of pollutants in the diet of 

 native Inuit. 



The Third Joint US-USSR Bering & Chukchi Seas 

 Expedition took place on the RA' Akademik Korolev (Cruise 

 AK-47). The Soviet Union and United States share a border 

 between territorial waters in this region and, as a result, most 

 scientific studies have been on either the Soviet or American 

 side. The ecology and air masses of the area, however, do not 

 recognize this boundary and a comprehensive investigation is 

 not possible under these constraints. Because this study was 

 cosponsored by the US Department of the Interior and the 

 USSR Academy of Sciences we were able to cross the dateline 

 many times, providing the first complete survey of the area. 

 This paper will address levels of organochlorine compounds 

 found in the atmosphere, microlayer, and surface water during 

 Cruise AK-47, and focus on the air-sea exchange of 

 hexachlorocyclohexane (HCH) in the Bering and southern 

 Chukchi Seas. 



Hexachlorocyclohexane is an insecticide used throughout 

 the world and is available in two fomiulations. technical-HCH 

 and lindane. Technical-HCH is a mixture of five isomers in the 

 following proportions (Metcalf, 1955): a 55-80%; 

 (3, 5-14%; Y. 8-15%; 5, 2-16%; and e. 3-5%. Although all 

 isomers are toxic, only the gamma isomer is insecticidal, and 

 it is produced in pure form as the insecticide lindane. The 

 limited data available about the tonnages of HCH used in 

 Northern Hemisphere countries are summarized in Table 1. 

 Most listings are from the United Nations Food and Agricultural 



Organization Production yearbooks (FAO. 1985, 1987). These 

 should be considered lower limits of actual usage because 

 many countries do not report such statistics to the FAO. 

 Nevertheless, a usage pattern of technical-HCH in Asia and 

 lindane in Europe can be seen. No use of technical-HCH in 

 Europe during the 1980's is reported by the FAO. 

 Technical-HCH has not been used in the United States since 

 1978, when manufacturers canceled their registrations or 

 switched them to lindane, which is still registered for application 

 (EPA, 1980a.b, 1985). The Soviet Union currently uses a 

 fortified mixture of HCH that consists of 90% y-HCH with the 

 balance composed of the other isomers (IRPTC, 1983). 



The deposition of organic compounds from the atmosphere 

 is controlled by their physical properties. Vapor pressures and 

 water solubilities of the HCH's are sufficiently high that they 

 remain primarily as gases in the atmosphere or dissolved in the 

 water column with relatively small fractions sorbed onto 

 particles (0.5-2.5%) (Tanabe & Tatsukawa, 1983; Bidleman, 



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