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Arsenic
Chromium VI Dense Nonaqueous Phase Liquids (DNAPLs) 1,4-Dioxane Mercury MTBE Perchlorate POPs PCBs TCE Other Contaminants
Environmental Occurrence Arsenic is a naturally occurring element, generally found at higher concentrations in sedimentary rocks than in other rock types. Arsenic is also commonly associated with sulfide deposits. In the continental United States a higher than average arsenic concentration is associated with sandstones, shales and coal located in Colorado, Utah, South Dakota, and Wyoming and with phoshorites in Arkansas, Idaho, Montana, South Carolina, and Wyoming. Shales, clays, and sedimentary iron and manganese oxides can also be rich in arsenic. Groundwater concentrations of arsenic tend to be higher in the west, especially parts of Arizona, Idaho, Nevada, New Mexico, Oregon, Utah, and Washington, than in the east. Parts of the Midwest states including Indiana, Michigan, and Wisconsin can also have relatively high concentrations of naturally occurring arsenic in groundwater. Major anthropogenic sources of arsenic in the environment include smelting operations and chromated copper arsenate (CCA), a variety of pesticide used in pressure treating wood for construction purposes. When used as a wood preservative, CAA has the potential to leach out of the wood over time. As a result, the wood treating industry has made a decision to eliminate all arsenical wood preservatives from residential use by the end of 2003. Organic arsenical pesticides are widely used for weed control. Inorganic arsenicals were largely used in the past to control specific insects, but for the most part, their registrations have been cancelled. They do, however, persist in fields and orchards where they were applied. Since arsenic is associated with sulfide deposits, which are in turn associated in many cases with non-ferrous ores, contamination can occur from mining operations and wastes. The smelting of non-ferrous ores has often resulted in air deposition of arsenic and other heavy metals (1). Arsenic is listed as the highest priority contaminant on the ATSDR/EPA priority list of hazardous substances at Superfund sites (ATSDR list). From a world-wide perspective: Maps Equal-area map: Arsenic concentrations found in at least 25% of ground-water samples within a moving 50km radius [View] County map: Arsenic concentrations found in at least 25% of ground-water samples in each county [View] Data map: 31,350 ground-water arsenic samples collected in 1973-2001 [View] For Further Information Arsenic Contribution from Dietary Sources Provides the results from cooking studies, a market basket survey, a food diary analysis, and the relationships between environmental and biological media; to be used in scenario-based models that predict arsenic exposures. Arsenic in Ground Water: Geochemistry and Occurrence
Arsenic in Ground Water of the United States Arsenic in Ground Water of the Willamette Basin, Oregon Arsenic: Medical and Biological Effects of Environmental Pollutants
Elements and Their Compounds in the Environment: Occurrence, Analysis and Biological Relevance, Second Edition
A digital version of the data can be obtained from David Smith, dsmith@usgs.gov. Geochemical Landscapes of the Conterminous United States: New Map Presentations for 22 Elements
State Arsenic Information Pages Illinois Department of Natural Resources
The Materials Flow of Arsenic in the United States This report presents a study of the flow of arsenic-containing materials in the United States, based on the best data available in 1991. It includes a consideration of arsenic as a byproduct of the processing of nonferrous metals, the fate of arsenic in manufacturing wastes, the quality of arsenic used in products, the fate of arsenic in dissipative uses, and the useful life of discarded products. Where possible, estimates are given of the amounts of arsenic lost from the materials flow. USGS Arsenic Studies Group 1. M. Focazio, et al. A Retrospective Analysis on the Occurrence of Arsenic in Ground-Water Resources of the United States and Limitations in Drinking-Water-Supply Characterizations. U.S. Geological Survey Water-Resources Investigations Report 99-4279, 2000. 2. Environmental Health Criteria 224: Arsenic and Arsenic Compounds |