The Toxic Substances Hydrology Program provides objective scientific information on environmental contamination to improve characterization and management of contaminated sites, to protect human and environmental health, and to reduce potential future contamination problems. Read more about the Toxics Program

Recent Headlines view all headlines				Research Projects view all research
New Approach to Evaluating Selenium Toxicity in the Environment Fish in Some Streams Accumulate Mercury A New Source of Methylmercury Entering the Pacific Ocean USGS Contributes to the Design of a Proposed National Mercury Monitoring Network (MercNet) Detergents in Streams May Just Disappear Pesticides are Detected in Vernal Pools in Parks and Wildlife Refuges				Subsurface Point-Source Contamination Projects: Petroleum (crude, gasolene, produced water) | Chlorinated Solvents | Mixed Wastes (landfills, wastewater) | Fractured-Rock Aquifers  Watershed-and Regional Scale Contamination Projects: Hard-Rock Mining | Pesticides | Emerging Contaminants | Mercury | Amphibian Research | Priority Ecosystems  Methods Development Topics: Microbial Geochemistry | Geochemistry | Hydrology | Contaminant Geophysics | Modeling
				Crosscutting Topics view all topics
				Agricultural Chemicals  Contaminant Occurrence Studies  Contaminant Plume Geochemistry and Microbiology  Geophysical Characterization  Ground-Water Contaminant Transport  Methods  Models  Natural Attenuation  Nutrients  Site Remediation  Surface-Water Contaminant Transport  Tracer Tests  Unsaturated Zone
				Photo Gallery view gallery
				Downstream view of Pinal Creek, AZ, where a tracer solution was injected into the stream during a tracer test. Water-quality sampling crews can be seen in the distance -- from the Tracer Tests Photo Gallery
New Publications view all publications				Meetings view all meetings
Selected New Publications Antidepressant pharmaceuticals in two U.S. effluent-impacted streams--Occurrence and fate in water and sediment, and selective uptake in fish neural tissue: Schultz, M.M., Furlong, E.T., Kolpin, D.W., Werner, S.L., Schoenfuss, H.L., Barber, L.B., Blazer, V.S., Norris, D.O., and Vajda, A.M., 2010, Environmental Science and Technology, doi:10.1021/es9022706 (Advanced Web release). In situ measurements of volatile aromatic hydrocarbon biodegradation rates in groundwater: Cozzarelli, I.M., Bekins, B.A., Eganhouse, R.P., Warren, E., and Essaid, H.I., 2010, Journal of Contaminant Hydrology, v. 111, no. 1-4, p. 48-64 doi:10.1016/j.jconhyd.2009.12.001. Patterns of mercury dispersion from local and regional emission sources, rural Central Wisconsin, USA: Kolker, A., Olson, M.L., Krabbenhoft, D.P., Tate, M.T., and Engle, M.A., 2010, Atmospheric Chemistry and Physics, v. 10, no. 1, p. 1823-1846. Upcoming Publications Analysis of solvent dyes in refined petroleum products by electrospray ionization mass spectrometry: Rostad, C.E., Fuel, doi:10.1016/j.fuel.2009.09.011 (IN PRESS). The effect of planting method on Populus Spp. and Salix Sp. mortality and growth at a petroleum-hydrocarbon contaminated shallow aquifer: Cook, R.L., Landmeyer, J.E., Atkinson, B., Messier, J.P., and Guthrie Nichols, E., International Journal of Phytoremediation (IN PRESS). Interpretation of a transient storage model of stream solute transport applied to overlapping spatial scales: Gooseff, M.N., Briggs, M.A., Bencala, K.E., McGlynn, B.L., and Scott, D.T., Limnology and Oceanography--Methods (IN PRESS).				USGS cosponsors the special session Fate and Transport of Radionuclides in the Environment at the 2009 AGU Fall Meeting, San Francisco, California, December 14-18, 2009 USGS cosponsors the special session Nutrient Sources and Cycling in Aquatic Systems at the 2009 AGU Fall Meeting, San Francisco, California, December 14-18, 2009 USGS cosponsors the special session Fate and Behavior of Pharmaceuticals in Treated Wastewaters, Sludge and River Waters at the SETAC 30th Annual Meeting, New Orleans, Louisiana, November 19-23, 2009 The USGS sponsored the special session Endocrine Disrupting Chemicals--Analytical Methods and Environment Processes at the SETAC 30th Annual Meeting, New Orleans, Louisiana, November 19-23, 2009 USGS and Montana Tech of the University of Montana co-sponsor the Special Session Diurnal Biogeochemical Processes in Rivers, Lakes, and Shallow Groundwater at the 2009 GSA Annual Meeting, Portland, Oregon, October 18-21, 2009 USGS science featured at the AAAS symposium San Francisco Bay: Tracking and Understanding a Changing Estuary, San Francisco, California, August 17, 2009 USGS and Colorado State University co-sponsor EmCon2009-2nd International Conference on Occurrence, Fate, Effects, and Analysis of Emerging Contaminants in the Environment, Fort Collins, Colorado, August 4-7, 2009 USGS, University of Texas at El Paso, and the Mountain Studies Institute conducted a field trip on Acid Rock Drainage in the San Juans in Prospect Gulch, near Silverton, Colorado, on August 1, 2009.