Evaluation of the validity of the US EPA's cancer risk assessment of arsenic for low-level exposures: A likelihood ratio approach

How Ran Guo, Peter A. Valberg

Research output: Contribution to journalReview article

16 Citations (Scopus)

Abstract

Skin cancers associated with ingesting of arsenic have been documented since the 19th century. A study in the southwestern coastal area of Taiwan where people drank well water containing arsenic is generally recognised as providing the best data available for quantifying the risk, and the US Environmental Protection Agency (EPA) used these data to conduct a risk assessment of arsenic ingestion. However, the lowest exposure category in the Taiwan study included arsenic levels up to 290 μg L-1, which is nearly six times higher than the current EPA maximum contaminant level (MCL), 50 μg L-1. Therefore, the EPA risk assessment model extrapolated data on high-level exposures to generate risk estimates for low-level exposures. To evaluate the validity of this model, we conducted a quantitative review of epidemiological studies observing arsenic exposures below 290 μg L-1. A ratio of the likelihood of the EPA model being inappropriate to that of it being appropriate was calculated for each study population as a measurement of the validity of the EPA model. Although existing human data on low-level exposures are limited, the review suggested that the EPA model is unlikely to be able to predict the risk of skin cancer accurately when the arsenic exposure level is between 170 and 270 μg L-1.

Original languageEnglish
Pages (from-to)133-142
Number of pages10
JournalEnvironmental Geochemistry and Health
Volume19
Issue number4
Publication statusPublished - 1997 Jan 1

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Environmental Protection Agency
Arsenic
Risk assessment
arsenic
risk assessment
cancer
skin
Skin
well water
evaluation
cancer risk
exposure
environmental protection agency
Impurities
pollutant
Water

All Science Journal Classification (ASJC) codes

  • Environmental Engineering
  • Environmental Chemistry
  • Water Science and Technology
  • Environmental Science(all)
  • Geochemistry and Petrology

Cite this

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Evaluation of the validity of the US EPA's cancer risk assessment of arsenic for low-level exposures : A likelihood ratio approach. / Guo, How Ran; Valberg, Peter A.

In: Environmental Geochemistry and Health, Vol. 19, No. 4, 01.01.1997, p. 133-142.

Research output: Contribution to journalReview article

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