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Die Ergebnisse der vorliegenden Studie zeigen, dass eine Kläranlage eine Quelle für Polyfluorierte Verbindungen (PFCs) in der Atmosphäre darstellt. Generell waren die mittlere Konzentrationen in der Gas- und Partikelphase am Belebungsbecken höher als am Nachklärbecken (Fluortelomeralkohole[FTOHs]: 11000 und 590 pg m-3, Perfluorooktansulfonamide und Perfluoroktansulfonamidethanole [FOSAs & FOSEs]: 120 und 30 pg m-3 und Perfluoroalkylcarboxylate und Perfluoroalkysulfonate [PFCAs & PFSAs]: 4000 und 1300 pg m-3). Partikelgebundene Anteile lagen bei ~3% für FTOHs, ~30% für FOSAs, ~40% für FOSEs, ~60–100% für PFCAs und ~98% für PFSAs, wobei der Anteil der PFCAs mit zunehmender Kettenlänge anstieg.Aktive und passive Probennahme wurden in der Studie miteinander verglichen und zeigten gute Übereinstimmung.

The enantiomers of chiral pesticides are often metabolised at different rates in soil and water, leading to nonracemic residues. This paper reviews enantioselective metabolism of organochlorine pesticides (OCPs) in soil and water, and the use of enantiomers to follow transport and fate processes. Residues of chiral OCPs and their metabolites are frequently nonracemic in soil, although exceptions occur in which the OCPs are racemic. In soils where enantioselective degradation and/or metabolite formation has taken place, some OCPs usually show the same degradation preference — e.g., depletion of (+)trans-chlordane (TC) and (–)cis-chlordane (CC), and enrichment of the metabolite (+)heptachlor exo-epoxide (HEPX). The selectivity is ambivalent for other chemicals; preferential loss of either (+) or (–)o,p’-DDT and enrichment of either (+) or (–)oxychlordane (OXY) occurs in different soils. Nonracemic OCPs are found in air samples collected above soil which contains nonracemic residues. The enantiomer profiles of chlordanes in ambient air suggests that most chlordane in northern Alabama air comes from racemic sources (e.g., termiticide emissions), whereas a mixture of racemic and nonracemic (volatilisation from soil) sources supplies chlordane to air in the Great Lakes region. Chlordanes and HEPX are also nonracemic in arctic air, probably the result of soil emissions from lower latitudes. The (+) enantiomer of α-hexachlorocyclohexane (α-HCH) is preferentially metabolised in the Arctic Ocean, arctic lakes and watersheds, the North American Great Lakes, and the Baltic Sea. In some marine regions (the Bering and Chukchi Seas, parts of the North Sea) the preference is reversed and (–)α-HCH is depleted. Volatilisation from seas and large lakes can be traced by the appearance of nonracemic α-HCH in the air boundary layer above the water. Estimates of microbial degradation rates for α-HCH in the eastern Arctic Ocean and an arctic lake have been made from the enantiomer fractions (EFs) and mass balance in the water column. Apparent pseudo first-order rate constants in the eastern Arctic Ocean are 0.12 year-1 for (+)α-HCH, 0.030 year-1 for (–)α-HCH, and 0.037 year-1 for achiral Υ-HCH. These rate constants are 3–10 times greater than those for basic hydrolysis in seawater. Microbial breakdown may compete with advective outflow for long-term removal of HCHs from the Arctic Ocean. Rate constants estimated for the arctic lake are about 3–8 times greater than those in the ocean.

The cryosphere is an important component of global organic contaminant cycles. Snow is an efficient scavenger of atmospheric organic pollutants while a seasonal snowpack, sea ice, glaciers and ice caps are contaminant reservoirs on time scales ranging from days to millennia. Important physical and chemical processes occurring in the various cryospheric compartments impact contaminant cycling and fate. A variety of interactions and feedbacks also occur within the cryospheric system, most of which are susceptible to perturbations due to climate change. In this article, we review the current state of knowledge regarding the transport and processing of organic contaminants in the global cryosphere with an emphasis on the role of a changing climate. Given the complexity of contaminant interactions with the cryosphere and limitations on resources and research capacity, interdisciplinary research and extended collaborations are essential to close identified knowledge gaps and to improve our understanding of contaminant fate under a changing climate., Atmospheric Chemistry and Physics, 13 (6), ISSN:1680-7375, ISSN:1680-7367