Source apportionment and measurement of PCBs and POPs in NY/NJ area.

摘要

Investigating the source of Persistent Organic Pollutants in ambient air and water is imperative in the development and implementation of Total Maximum Daily Load (TMDL) process for the impaired water bodies. Atmospheric deposition is an important process involved in the TMDL modeling, therefore one objective of this thesis aims to achieve is how to identify PCB source types and regions in air. The coupling of Positive matrix factorization (PMF) model, which is use to apportion the contributing sources, with potential source contribution function (PSCF) model, which is used to locate the source regions, allowed the identification of PCB sources in urban air in Camden, US. Four factors are identified which are thought to represent sources such as volatilized Aroclors and particle-phase PCBs. The PSCF model output for SigmaPCBs and the resolved factors suggests that the urban PCB signal is comprised of multiple signals, some of which may come from discrete sources that can be identified and remediated.;As an attempt to refine the atmospheric deposition modeling input, passive sampling study is conducted to investigate the spatial extent of the urban-impacted elevated atmospheric persistent organic pollutants (POPs) including PCBs, PAHs, OCPs and BDEs by deploying passive samplers at 32 sites across the Philadelphia --Camden area. This study revealed two maxima for PCBs representative of urban (population density driven) sources vs. industrial sources, highlighting the potential role of densely populated urban centers as well as industrial areas as sources of PCBs to the regional environment. PAHs and BDEs all showed urban-rural gradients with maximum concentrations found in the urban center. Some of OCPs showed urban-rural gradient, while others exhibited either a relatively uniform concentration level across the sampling area or a relatively random spatial distribution.;In order to corroborate the loading estimate used in the development of TMDL, PMF model is also used to apportion the source of PCBs in Delaware River and NY/NJ Harbor Estuary. The analysis of ambient water either generally corroborates the PCB loading estimate used in the water quality model or identified factors associated with top loading categories in previous mass balance study.