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PubMed · 8571397

Risk-based concentrations: prioritizing environmental problems using limited data.

R L Smith
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Abstract

A difficult task faced by regulatory agencies is that of choosing, on the basis of limited data, which environmental problems to address. This paper incorporates USEPA risk assessment methods into a quantitative approach for prioritizing locations, contaminants and media according to potential health risk. USEPA has developed either a reference dose (a chronic dose without adverse effect) or slope factor (upper bound lifetime cancer risk per mg.kg-1.d-1) for many substances. This work combines these 'toxicological constants' with predetermined risk levels (either a 10(-6) cancer risk or a chronic intake equal to the reference dose) and protective human exposure assumptions (e.g. 70-kg body mass, 30-year exposure, 2-1.d-1 drinking water ingestion, etc.) to produce risk-based concentrations for 596 contaminants in air, drinking water, edible fish and soil. Because USEPA designed its methods to estimate upper bound risks, these risk-based concentrations are likely to be protective of human health. Regulatory officials can use this information to calculate numerical ratios between measured environmental levels and risk-based concentrations. These ratios serve as a surrogate for potential health impacts and can be used to prioritize problems for attention. Ratio calculation and ranking can be automated for searches of computerized environmental databases.

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AdultAir PollutantsCarcinogensChildData Interpretation, StatisticalEnvironmental ExposureEnvironmental MonitoringHazardous SubstancesHealth PrioritiesHumansRisk AssessmentSoil PollutantsToxicity TestsUnited StatesUnited States Environmental Protection AgencyWater PollutantsJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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R L Smith. 1996-01-08. Risk-based concentrations: prioritizing environmental problems using limited data.. https://doi.org/10.1016/0300-483x(95)03165-c

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