Introduction into the environment of elements (such as arsenic, cadmium, lead, and mercury) which have a deleterious effect on living organisms when found naturally in only minor amounts (concentrations less than 1.0 milligram per liter) in water or sediment.
Trace elements are inorganic chemicals occurring in small amounts in nature. This web site of the National Water Quality Assessment links to U.S. data, publications, news, and other sites on trace metals, metalloids and radionuclides in water.
Overview of three research programs including determining levels of mercury at selected sites in water, sediment and fish, mercury emissions into the atmosphere, and mercury cycling in the Everglades National Park, Florida.
Homepage for the Toxic Substances Hydrology Program, which provides scientific information on contaminated sites and on human and environmental health. Links to news, topical information, investigations, meetings, publications, and photos.
Outlines processes that control the release of metals and acidic waters from inactive mines and mineralized areas, the transport of metals and acidic waters to streams, and the fate and effect of metals and acidity on downstream ecosystems.
Contaminants from mines move more easily from ore materials and mine waste piles to surrounding estuaries and living organisms when water moves through the mine site. Geochemical results shown here will help people mitigate the negative effects.