Abstract
Within the Hudson River Estuary, samples of air, aerosols, and precipitation were collected at nine sites chosen to represent different land uses, and concentrations of PCBs were measured. The samples were collected at regular intervals from October 1997 through May 2001. The measured concentrations were used to calculate deposition fluxes to the estuary. Results showed that the gas-phase total PCB concentrations varied over more than two orders of magnitude from site to site, and highest concentrations were measured in the urbanized areas of Camden and Jersey City, NJ, which also had the highest gross gas absorption. Concentrations in the forested, coastal, and suburban sites were essentially the same and similar to concentrations observed at remote areas surrounding the Great Lakes. Total PCBs in the particulate phase generally followed the same spatial trends as in the gas phase, and dry-deposition fluxes were generally higher in urban areas due to higher particle-phase PCB concentrations. The spatial variations in PCB concentrations in precipitation also mirrored those of the gas phase. Gas absorption represented 75-85% of the total PCB deposition at all sites except Delaware Bay, while dry deposition comprised 10-17% and wet deposition comprised 4-8%.