CONCNURRENT EXPOSURE ASSESSMENTS OF ATRAZINE AND METOLACHL OR IN THE MAINSTEM, MAJOR TRIBUTARIES AND SMALL STREAMS OF THE CHESAPEAKE BAY WATERSHED: INDICATORS OF ECOLOGICAL RISK

摘要

The goals of this study were to: (1) measure atrazine and metolachlor concentrations during both high and low use periods in the Chesapeake Bay's mainstem/major tributaries, smaller tributaries and representative small agricultural streams during 1995 and 1996; (2) compare these exposure data with toxicity benchmarks for each herbicide to predict ecological risk and (3) use in-stream fish community data collected in the streams to provide supportive data for ecological risk characterization.