Flawed analysis of an intentional human dosing study and its impact on chlorpyrifos risk assessments.

Details

• Personal Author:
  Fenske RA ; McGrew S ; Sheppard L
• Description:
  In March 1972, Frederick Coulston and colleagues at the Albany Medical College reported results of an intentional chlorpyrifos dosing study to the study's sponsor, Dow Chemical Company. Their report concluded that 0.03 mg/kg-day was the chronic no-observed-adverse-effect-level (NOAEL) for chlorpyrifos in humans. We demonstrate here that a proper analysis by the original statistical method should have found a lower NOAEL (0.014 mg/kg-day), and that use of statistical methods first available in 1982 would have shown that even the lowest dose in the study had a significant treatment effect. The original analysis, conducted by Dow-employed statisticians, did not undergo formal peer review; nevertheless, EPA cited the Coulston study as credible research and kept its reported NOAEL as a point of departure for risk assessments throughout much of the 1980's and 1990's. During that period, EPA allowed chlorpyrifos to be registered for multiple residential uses that were later cancelled to reduce potential health impacts to children and infants. Had appropriate analyses been employed in the evaluation of this study, it is likely that many of those registered uses of chlorpyrifos would not have been authorized by EPA. This work demonstrates that reliance by pesticide regulators on research results that have not been properly peer-reviewed may needlessly endanger the public. [Description provided by NIOSH]
• Subjects:
  Agriculture Environmental Exposure Insecticides Occupational Health Safety
• Keywords:
  Agriculture; Chlorpyrifos; Pesticides And Agricultural Chemicals; Statistical Analysis; Risk Assessment; Organophosphorus Insecticides; Children; Environmental Exposure; Permissible Limits; Author Keywords: Chlorpyrifos; Risk Assessment; Human Toxicological Study; Linear Mixed Model; Repeated Measures Analysis Of Variance; No Observable Adverse Effect Level
• ISSN:
  0160-4120
• Document Type:
  Text
• Funding:
  Cooperative Agreement
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 10 ; Washington
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  143
• NIOSHTIC Number:
  nn:20065432
• Citation:
  Environ Int 2020 Oct; 143:105905
• Contact Point Address:
  Lianne Sheppard, Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA 98195, USA
• Email:
  sheppard@uw.edu
• CAS Registry Number:
  Chlorpyrifos (CAS RN 2921-88-2)
• Federal Fiscal Year:
  2021
• NORA Priority Area:
  Agriculture, Forestry and Fishing
• Performing Organization:
  University of Washington
• Peer Reviewed:
  True
• Start Date:
  20010930
• Source Full Name:
  Environment International
• End Date:
  20270929
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:1c2dc756331859661b6c30f95cbaedcbd82d34c5641dd4929938730abcfc302aa2de99132776bd532588716750a780ca54daa61737dcd82437bee4bc9e44ab3c
• Download URL:
  https://stacks.cdc.gov/view/cdc/248892/cdc_248892_DS1.pdf
• File Type:
  [PDF - 1.27 MB ]