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Chlorpyrifos: EPA's Request for Columbia's Raw Data

In 2007, EPA received a petition from PANNA and NRDC asking the Agency to revoke the tolerances for the pesticide chlorpyrifos.

Prior to 2013, EPA requested the dataset from an epidemiology study conducted by the Columbia Center for Children's Environmental Health (CCCEH) which EPA used as the reasoning behind a proposed rule in November 2015 to revoke the tolerances for chlorpyrifos, potentially banning the pesticide from use.  EPA had a March 31, 2017 court-ordered deadline to make a decision on the PANNA/NRDC petition seeking a ban.   

The Columbia Center study has been widely-used as support for a ban, despite divergent scientific views among EPA scientific review panels and USDA questioning the study and its data:

  • 2016 EPA Scientific Advisory Panel: "Some Panel members thought the quality of the CCCEH data is hard to assess when raw analytical data have not been made available, and the study has not been reproduced."
  • 2017 USDA letter: Recommends denying the petition citing EPA's Scientific Integrity Policy: "USDA has grave concerns that ambiguous response data from a single, inconclusive study are being combined with a mere guess as to dose levels, and the result is being used to underpin a regulatory decision …"

Given that the Ninth Circuit would not provide additional time for a new administration to review the issue, EPA denied the petition, based on the lack of time, divergent views from the cabinet departments and the fact that the scheduled FIFRA review for all pesticides, including chlorpyrifos, allows for a public process that included more time to further evaluate the science and come to a clearer scientific resolution of the issues.

EPA Requests for Columbia Study's Data

Despite multiple requests, an EPA visit to Columbia, and a public commitment to "share all data gathered," CCCEH has not provided EPA with the data used. You can find a discussion of EPA's requests in the following documents:

  1. December 29, 2014: EPA revised Human Health Risk Assessment - see Appendix 6: CCCEH Epidemiology Data Acquisition "Raw Data" Request on page 384
  2. April 19, 2016: EPA letter to Linda P. Fried, Dean, Mailman School of Public Health
  3. May 18, 2016: Linda P. Fried, Dean, Mailman School of Public Health letter to EPA
  4. June 27, 2016: EPA letter to Linda P. Fried, Mailman School of Public Health
  5. January 17, 2017: USDA letter to EPA citing Scientific Integrity Policy
  6. January 2, 2018: EPA letter to Linda Fried, once again requesting dataset
  7. January 8, 2018: Email from Linda Fried saying EPA needs to "clarify the information requests"