HR: 0800h
AN: H41C-0656    [Abstracts]
TI: Current-Use Pesticides and Organochlorine Compounds in Precipitation and Lake Sediment from Two High-Elevation National Parks
AU: * Mast, M A
EM: mamast@usgs.gov
AF: USGS Colorado Water Science Center, MS 415, Denver Federal Center, Denver, CO 80225, United States
AU: Foreman, W T
EM: wforeman@usgs.gov
AF: USGS National Water Quality Laboratory, MS 407, Denver Federal Center, Denver, CO 80225, United States
AB: Current-use pesticides (CUPs) and banned organochlorine compounds (OCCs) were measured in precipitation and lake sediments from two national parks in the Western U.S. to determine their occurrence and distribution in high-elevation environments. CUPs frequently detected in snow were endosulfan, dacthal, and chlorothalonil in concentrations ranging from 0.07 to 2.4 ng/L. Of the OCCs, only chlordane, HCB, and two PCB congeners were detected. Pesticides most frequently detected in rain were atrazine, carbaryl, and dacthal in concentrations from 3.0 to 95 ng/L. Estimated annual deposition rates in one of the parks were 8.4 μg/m² for atrazine, 9.9 μg/m² for carbaryl, and 2.6 μg/m² for dacthal of which over 85% occurred during summer. DDE and DDD were the most frequently detected OCCs in lake sediments. DDD and DDE concentrations in an age dated sediment core suggest that atmospheric deposition of banned OCCs, to high-elevation areas have been in decline since the 1970s. Dacthal and endosulfan sulfate were present in low concentrations (0.11–1.2 μg/kg) and were the only CUPs detected in lake sediments.
DE: 0478 Pollution: urban, regional and global (0345, 4251)
DE: 0496 Water quality
DE: 0736 Snow (1827, 1863)
DE: 1803 Anthropogenic effects (4802, 4902)
DE: 1836 Hydrological cycles and budgets (1218, 1655)
SC: Hydrology [H]
MN: 2007 Fall Meeting