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Title: Research approaches to address uncertainties in the risk assessment of arsenic in drinking water

Abstract

Inorganic arsenic (iAs), an environmental drinking water contaminant, is a human toxicant and carcinogen. The public health community has developed recommendations and regulations that limit human exposure to iAs in drinking water. Although there is a vast amount of information available to regulators on the exposure, disposition and the health-related effects of iAs, there is still critical information about the toxicology of this metalloid that is needed. This necessary information includes identification of the chemical species of arsenic that is (are) the active toxicant(s), the mode(s) of action for its various toxicities and information on potentially susceptible populations. Because of these unknown factors, the risk assessment of iAs still incorporates default assumptions, leading to uncertainties in the overall assessment. The characteristics of a scientifically defensible risk assessment for iAs are that it must: (1) quantitatively link exposure and target tissue dose of active metabolites to key events in the mode of action for major health effects and (2) identify sources of variation in susceptibility to arsenic-induced health effects and quantitatively evaluate their impact wherever possible. Integration of research to address these goals will better protect the health of iAs-exposed populations.

Authors:
 [1]; ;  [2]
  1. U.S. Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, MD B143-01, Research Triangle Park, NC 27711 (United States), E-mail: hughes.michaelf@epa.gov
  2. U.S. Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, MD B143-01, Research Triangle Park, NC 27711 (United States)
Publication Date:
OSTI Identifier:
21077773
Resource Type:
Journal Article
Resource Relation:
Journal Name: Toxicology and Applied Pharmacology; Journal Volume: 222; Journal Issue: 3; Other Information: DOI: 10.1016/j.taap.2007.01.021; PII: S0041-008X(07)00068-3; Copyright (c) 2007 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; ARSENIC; CARCINOGENS; DRINKING WATER; METABOLITES; NEOPLASMS; PUBLIC HEALTH; RECOMMENDATIONS; RISK ASSESSMENT; TOXICITY

Citation Formats

Hughes, Michael F., Kenyon, Elaina M., and Kitchin, Kirk T. Research approaches to address uncertainties in the risk assessment of arsenic in drinking water. United States: N. p., 2007. Web. doi:10.1016/j.taap.2007.01.021.
Hughes, Michael F., Kenyon, Elaina M., & Kitchin, Kirk T. Research approaches to address uncertainties in the risk assessment of arsenic in drinking water. United States. doi:10.1016/j.taap.2007.01.021.
Hughes, Michael F., Kenyon, Elaina M., and Kitchin, Kirk T. 2007. "Research approaches to address uncertainties in the risk assessment of arsenic in drinking water". United States. doi:10.1016/j.taap.2007.01.021.
@article{osti_21077773,
title = {Research approaches to address uncertainties in the risk assessment of arsenic in drinking water},
author = {Hughes, Michael F. and Kenyon, Elaina M. and Kitchin, Kirk T.},
abstractNote = {Inorganic arsenic (iAs), an environmental drinking water contaminant, is a human toxicant and carcinogen. The public health community has developed recommendations and regulations that limit human exposure to iAs in drinking water. Although there is a vast amount of information available to regulators on the exposure, disposition and the health-related effects of iAs, there is still critical information about the toxicology of this metalloid that is needed. This necessary information includes identification of the chemical species of arsenic that is (are) the active toxicant(s), the mode(s) of action for its various toxicities and information on potentially susceptible populations. Because of these unknown factors, the risk assessment of iAs still incorporates default assumptions, leading to uncertainties in the overall assessment. The characteristics of a scientifically defensible risk assessment for iAs are that it must: (1) quantitatively link exposure and target tissue dose of active metabolites to key events in the mode of action for major health effects and (2) identify sources of variation in susceptibility to arsenic-induced health effects and quantitatively evaluate their impact wherever possible. Integration of research to address these goals will better protect the health of iAs-exposed populations.},
doi = {10.1016/j.taap.2007.01.021},
journal = {Toxicology and Applied Pharmacology},
number = 3,
volume = 222,
place = {United States},
year = 2007,
month = 8
}
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