Over-Water and Over-Land Polychlorinated Biphenyls in Green Bay, Lake Michigan

Abstract

Air samples were simultaneously collected over water and over nearby land in the Green Bay, Lake Michigan, region and analyzed for 85 polychlorinated biphenyls (PCBs). The concentration and distribution of PCB congeners collected from vapor over water, over land, and dissolved in the water support the hypothesis that volatilization of PCBs from contaminated waters is a major source of PCBs to the local atmosphere. Concentrations of PCB congener (∑PCBs) over the water are higher over southern Green Bay (670–2200 pg/m3) and lower over the northern bay (160–520 pg/m3) while ∑PCB concentrations over the land ranged from 70 to 760 pg/m3. The PCB concentration differences over land and over water were statistically significant for congener sums and for homolog groups in southern Green Bay. Regressions of air and water PCB distributions show high correlations (R2 = 0.73–0.96) in southern Green Bay. © 1993, American Chemical Society. All rights reserved.