Regional patterns of contaminants (PAH,pesticides and trace metals) in snow of Northeast Bavaria and their relationship to human influence and orographic effects

In January 1978, 31 snow samples were collected throughout NE-Bavaria and were analyzed for trace metals (Zn, Pb, Cd, Cu), pesticides (α-BHC, Lindane, Aldrin, Dieldrin) and polycyclic aromatic hydrocarbons (PAH) (3,4-benzopyrene, 1,12-benzoperylene, fluoranthene and 3,4-(o-phenylene)-pyrene). The regional pattern of PAH-concentrations can be explained as follows: above urban areas and through orographic uplifting of the air, PAH's are scavenged from the atmosphere by snow. The trace metals and specific conductance show similar regional patterns, although the pattern for Pb is influenced by automobile traffic as well as by glass and ceramic industries. The pesticides show less distinct patterns relative to the other two groups of contaminants. Using multivariate statistics it was shown that the trace metals with the exception of Pb and the PAH's had regional patterns similar to each other but distinct from the pesticides. Although orography, urbanization and industries are shown to affect the regional patterns of PAH's and the trace metals, this is not the case for pesticides. They originate from diffuse sources in agricultural and f forested lands.