Summary

The New York/New Jersey Harbor Estuary receives substantial inputs of organic contaminants from upstream Hudson River flow, other tribu tary flow, discharge of wastewater treatment plants and CSOs, resuspension of historically contaminated sediments, and atmospheric deposition. Farley et al. (1999) has described the PCB and other organic chemical inputs to the New York/New Jersey Harbor Estuary and has concluded that PCB volatilization from the river and estuarine waters may be an important loss term for the water column. We have estimated the contributions of wet and dry particle deposition and atmospheric gas phase absorption across the water surface of PCBs and PAHs to the estuary to total atmospheric deposition. Although gas absorption of PCBs dominates inputs, loss by volatilization exceeds atmospheric deposition by approximately five times. Total PCB loading from the atmosphere is about 30-90 ng m-2 d-1 depending on which land-based data are used. Atmospheric fluxes to the estuary due to precipitation and dry particle deposition are perhaps two to ten times fluxes reported for the other systems. If gas absorptive inputs are included, total atmospheric fluxes increase by five to ten times. These fluxes are lower than the PCB accumulation rates in wetland sediments at the lower end of Long Island Sound, which may represent an atmospheric input signal. Comparing only wet and dry particle deposition for PAHs amongst the New York/New Jersey Harbor Estuary, Great Lakes, and Chesapeake Bay, the New York/New Jersey Harbor Estuary is loaded at a rate of approximately two to ten times the rates reported for the Great Lakes from IADN (Hoff et al., 1996;Hillery et al., 1998) and Chesapeake Bay from CBADS (Baker et al., 1997) from the 1990s. The absorptive input of gaseous PAHs dominates the atmospheric signal for the more volatile phenanthrene but plays no significant role for the mostly particle-bound BaP. The elevated atmospheric deposition of PAHs to the estuary is consistent with the proximity of higher local and regional emissions in the estuary and near its monitoring stations.

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