209 - Distribution and toxicity of pesticides and other contaminants in stream sediments in relation to urbanization
Lisa H. Nowell1, email@example.com, Patrick W. Moran2, Nile E. Kemble3, Christopher G. Ingersoll3, Kathryn M. Kuivila1. (1) California Water Science Center, U.S. Geological Survey, Sacramento, CA 95819, United States, (2) Washington Water Science Center, U.S. Geological Survey, Tacoma, WA 98402, United States, (3) Columbia Environmental Research Center, U.S. Geological Survey, Columbia, MO 65201, United States
To assess contributions of current and legacy pesticides and other contaminants to sediment toxicity in urban streams, organochlorine compounds, pyrethroid insecticides, polycyclic aromatic hydrocarbons (PAH), and trace elements were evaluated in stream sediment from seven metropolitan areas across the U.S. Organochlorine compounds, bifenthrin, PAHs, and six trace elements were significantly related to urbanization and (except bifenthrin) to sediment organic carbon. Differences in contaminant levels among study areas remained after accounting for effects of urbanization and sediment organic carbon using multiple regression. Potential toxicity, assessed using Probable Effect Concentration-Quotients (PEC-Q) and whole-sediment bioassays with the amphipod Hyalella azteca, increased with increasing urbanization. Mean PEC-Qs were dominated by trace elements at undeveloped sites, and organic contaminants (especially bifenthrin) at highly (>50%) urban sites. Amphipod toxicity was significantly related to the mean PEC-Q when bifenthrin was included. This study suggests bifenthrin is important to observed and predicted sediment toxicity in these urban streams.
Tuesday, March 23, 2010 03:15 PM
Pesticides and Urban Water Quality: Monitoring, Modeling and Mitigation (01:30 PM - 04:35 PM)
Location: The Moscone Center
Room: Room 3003 West Bldg.