Analysis of Agency Estimates of Risk for Carcinogenic Agents

  • John G. Cobler
  • Fred D. Hoerger
Part of the Advances in Risk Analysis book series (AEMB, volume 220)


Agency decisions involving 14 “carcinogens” were examined by an interdisciplinary group with experience in risk assessment. Analysis of these agency decisions led to observations and conclusions of broad applicability.

The scope of the data base available to the agencies was highly variable. This factor has contributed to a tendency to focus on bio-assay results for risk assessment rather than the total data base.

Reliance upon quantitative risk assessment by agencies has been varied. OSHA has not utilized quantitative risk assessment but based regulatory action on feasibility. EPA has relied largely upon a standardized logic pattern for carcinogen classification and a conservative policy which standardizes and confines judgmental consideration of data. FDA uses quantitative risk assessment with “prudent” scientific flexibility, but is limited in areas of applicability by statutory policy restraints.

Recent court decisions, such as the Supreme Court decision on benzene, increase the likelihood of use of risk assessment by the agencies, especially OSHA. There is variation in the level of risk control achieved by the agencies. For example, 16 of 21 agency instances of risk control were in the range of 1 in 10,000 to 1 in 1 million lifetime risks. Considering all the other agency decision displaced in this report, the majority of decisions cluster around 10-4 or 10-5.

Credible judgmental estimates of risk are two orders of magnitude lower than agency estimates. (Comparisons were possible with 6 of 14 substances.) Strong evidence suggests credible judgmental bases for adjusting agency estimates downward for an additional 5 of the 14 substances.


Carcinogens Carcinogenic Policies Regulation of Carcinogens Risk Assessment 


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Copyright information

© Plenum Press, New York 1985

Authors and Affiliations

  • John G. Cobler
    • 1
  • Fred D. Hoerger
    • 1
  1. 1.Health and Environmental SciencesMidlandUSA

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