HR: 14:30h
AN: H23A-03    [Abstracts]
TI: Occurrence of Pharmaceutical and Other Organic Compounds in Ground Water in Ten Regions of California, USA
AU: * Domagalski, J
EM: joed@usgs.gov
AF: U.S. Geological Survey, 6000 J Street, Placer Hall, Sacramento, CA 95819, United States
AU: Belitz, K
EM: kbelitz@usgs.gov
AF: U.S. Geological Survey, 4165 Spruance Road, Suite 200, San Diego, CA 92101, United States
AU: Furlong, E T
EM: efurlong@usgs.gov
AF: U.S. Geological Survey, Denver Federal Center, Lakewood, CO 80225, United States
AB: A State-wide assessment of the occurrence of pharmaceuticals, pesticides, and other anthropogenic and natural constituents in ground-water aquifers that are used for public supply is being made as part of the California Ground-Water Assessment and Monitoring Program (http:ca.water.usgs.gov/gama/). During the first three years of the program, a total of 682 wells were sampled in ten areas of California representing a wide range of climatic, land-use, population density, and hydrogeologic conditions. Although the wells were generally deep (greater than 100 meters below land surface), the percent of wells containing at least one pesticide ranged from 15 to 88 in the ten study areas. In contrast, the detection frequency of pharmaceuticals ranged from 5 to 22 percent. Concentrations of pharmaceutical compounds were generally less than 50 parts per trillion. Of the 14 pharmaceutical compounds investigated, only 3 were detected in more than half of the study areas (carbamazapine, acetaminophen, and sulfmethoxazole) and only one was detected in more than 2 percent of the wells (carbamapazine). These 3 compounds have low soil-water partition coefficients (Kd) and are presumably less degradable, with respect to the time of transport to the sampled portion of the aquifer, compared to the other compounds. These 3 compounds are also a subset of the pharmaceuticals that have been detected most frequently in surface water. Several other pharmaceutical compounds that are frequently detected in surface water but not abundant in this study have high Kd values, suggesting sorption onto aquifer solids may limit their sub- surface transport, or have faster degradation rates. The occurrence of pharmaceutical compounds is not well correlated with that of pesticides, but may be related to land-use as the highest detection frequency occurred in the study unit with the highest urban density.
DE: 0496 Water quality
DE: 1803 Anthropogenic effects (4802, 4902)
DE: 1831 Groundwater quality
DE: 1834 Human impacts
SC: Hydrology [H]
MN: 2007 Joint Assembly