U.S. EPA Contaminated Site Cleanup Information (CLU-IN)

U.S. Environmental Protection Agency
U.S. EPA Technology Innovation and Field Services Division



Arsenic poses a significant health risk to humans. Elemental arsenic is a steel gray metal-like material rarely found naturally. As a compound with other elements such as oxygen, chlorine, and sulfur, arsenic is widely distributed throughout the earth's crust, especially in minerals and ores that contain copper or lead (1). Arsenic in groundwater is largely the result of dissolved minerals from weathered rocks and soils (2).

All arsenic metal and compounds consumed in the United States are imported. Most of the arsenic has been used for the production of chromated copper arsenate (2), a preservative that renders wood resistant to rotting and decay. Increased environmental regulation, along with the decision of the wood treating industry to eliminate arsenical wood preservatives from residential application by the end of 2003, caused arsenic consumption in the U.S. to decline drastically in 2004 (2). Other industrial products containing arsenic include lead-acid batteries, light-emitting diodes, paints, dyes, metals, pharmaceuticals, pesticides, herbicides, soaps, and semiconductors. Man-made sources of arsenic in the environment include mining and smelting operations, agricultural applications, and disposal of wastes that contain arsenic.

Arsenic is a contaminant of concern at many remediation sites. Because arsenic readily changes valence states and reacts to form species with varying toxicity and mobility, effective treatment of arsenic can be challenging. In addition, in January 2001, EPA published a revised maximum contaminant level (MCL) for arsenic in drinking water. The revised MCL for arsenic in drinking water will result in lower treatment goals for Superfund arsenic treatment technologies, which may significantly affect their selection, design, and operation.

ATSDR Public Health Statement for Arsenic
Agency for Toxic Substances and Disease Registry, Sep 2000

Adobe PDF LogoEnvironmental Impacts of Preservative-treated Wood, 8-11 February 2004, Orlando, Florida [Proceedings]
Florida Center for Environmental Solutions, Gainesville. 387 pp, 2004

These conference papers and abstracts address the impacts of wood-preserving compounds containing chromium, copper, and arsenic on environmental media and biota, human health effects, disposal approaches, and innovative remediation technologies applicable to treated wood waste.

Adobe PDF LogoGroundwater Information Sheet: Arsenic
California State Water Resources Control Board, 9 pp, 2010.

This brief groundwater information sheet provides general information (fate and transport, health effects, testing and remediation methods) and identifies where high levels of the compound are found in California. The information is pulled from a variety of sources, and a bibliography is provided.

U.S. EPA Workshop on Managing Arsenic Risks to the Environment: Characterization of Waste, Chemistry, and Treatment and Disposal, May 1-3, 2001, Denver, Colorado: Proceedings and Summary Report
U.S. EPA, National Risk Management Research Laboratory, Cincinnati, OH.
EPA 625-R-03-010, 108 pp, 2003.

The workshop was convened by EPA's Office of Research and Development from May 1 - 3, 2001, to reevaluate many of the research issues dealing with managing arsenic in soils, sludge, and ground water from either anthropogenic or natural sources. This document contains a summary of key issues pertaining to managing arsenic risks to the environment and the presentations made in the plenary and breakout sessions.

1. "ToxFAQs for Arsenic." Aug 2007

2. "Arsenic," W.E. Brooks and R.L. Virta. U.S. Geological Survey Mineral Commodity Summaries 2005, p 24-26.