Karuppiah M, Gupta G
Department of Natural Sciences, University of Maryland Eastern Shore, Princess Anne 21853, USA.
Ecotoxicol Environ Saf. 1996 Oct;35(1):81-5. doi: 10.1006/eesa.1996.0084.
Chesapeake Bay and its tributaries are contaminated by industrial and municipal point sources and agricultural nonpoint sources of pollution. The objective of this study was to compare the porewater characteristics of two Chesapeake Bay tributaries: Wicomico River (WR) contaminated by point source and Pocomoke River (PR) contaminated by both point and nonpoint sources of pollution. Four study sites (1 mile before, adjacent to, and 1 and 2 miles after the sewage treatment plant) were chosen to collect sediment samples in both the rivers. The sediment-pore waters were analyzed for toxicity using Microtox marine luminescent bacteria-Vibrio fischeri. USEPA toxicity identification evaluation tests on these pore waters confirmed that the contaminants (ammonia and heavy metals) in WR were from municipal point sources, whereas in PR the contamination (metals, pesticides, and PCBs) was from nonpoint sources (agriculture) of pollution. The toxicity (and the concentration of contaminants) decreased both upstream and downstream from the most polluted site in both the rivers.
切萨皮克湾及其支流受到工业和城市点源污染以及农业面源污染的影响。本研究的目的是比较切萨皮克湾两条支流的孔隙水特征：受点源污染的威科米科河（WR）和受点源与面源污染的波科莫克河（PR）。在两条河流中选取了四个研究地点（污水处理厂前1英里处、相邻处、污水处理厂后1英里处和2英里处）来采集沉积物样本。使用Microtox海洋发光细菌——费氏弧菌对沉积物孔隙水进行毒性分析。美国环境保护局对这些孔隙水进行的毒性鉴定评估测试证实，威科米科河中的污染物（氨和重金属）来自城市点源，而波科莫克河中的污染物（金属、农药和多氯联苯）来自面源（农业）污染。两条河流中，毒性（以及污染物浓度）在最污染地点的上下游均有所降低。
