Jump to main content.


EPA's Response to "Health Risks from Dioxin and Related Compounds Evaluation of the EPA Reassessment" Published By the National Research Council of the National Academies (Interagency Science Consultation Draft)

Archive disclaimer
Archived files are provided for reference purposes only. The file was current when produced, but is no longer maintained and may now be outdated. Persons with disabilities having difficulty accessing archived files may contact the NCEA Webmaster for assistance. Please visit http://epa.gov/ncea to access current information.


Contact
Norman Birchfield
by phone at:   703-347-0174
by fax at:   703-347-8699
by email at:  birchfield.norman@epa.gov
On May 21, 2010, the updated EPA's Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments report was released for external peer review and public comment. This report was renamed after interagency comments from the original report title of EPA's Response to "Health Risks from Dioxin and Related Compounds Evaluation of the EPA Reassessment" Published by the National Research Council of the National Academies. The document was reviewed internally by EPA and by other federal agencies and White House Offices before public release. In the new IRIS process, introduced by the EPA Administrator, all written comments on IRIS assessments submitted by other federal agencies and White House Offices are made publicly available. Accordingly, interagency comments and the interagency science consultation draft report and the charge to external peer reviewers are posted on this site.

Downloads/Related Links

Background
In 2003, EPA, along with other federal agencies, asked the National Academy of Sciences (NAS) to review aspects of the science in EPA's draft dioxin reassessment entitled, Exposure and Human Health Reassessment of 2,3,7,8-Tetrachlorodibenzo-p-Dioxin (TCDD) and Related Compounds, and, in 2004, EPA sent the 2003 draft dioxin reassessment to the NAS for their peer review. The NAS held several public meetings during their review of the draft reassessment and on July 11, 2006, released the report of their review entitled, "Review of EPA's Assessment of the Health Implications of Exposure to Dioxins."

The NAS identified three areas in the 2003 draft reassessment that required substantial improvement to support a more scientifically robust risk characterization. These three areas were: (1) justification of approaches to dose-response modeling for cancer and non-cancer endpoints; (2) transparency and clarity in selection of key data sets for analysis; and (3) transparency, thoroughness, and clarity in quantitative uncertainty analysis. The NAS provided EPA with recommendations to address their key concerns. The Draft Response to Comments report, which is being provided for public review and comment, responds to the key recommendations included in NAS's 2006 report. This draft report includes significant new analyses on both the potential cancer and noncancer human health effects that may result from of exposures to dioxins. For instance, the Draft Response to Comments report addresses the explicit recommendation of the NAS to develop a quantitative risk estimate for noncancer effects that may result from long-term (chronic) oral exposure to dioxins. Thus, the Draft Response to Comments report includes an oral reference dose (RfD) for TCDD; the most well studied and considered to be the most toxic of the dioxin-like compounds. An RfD was not in the 2003 draft dioxin reassessment.

In addition, in 2003 EPA and other federal agencies developed a set of questions and answers related to dioxins. They have updated them about every year and a half. These materials have again been updated to include more recent information. These questions and answers provide general information on dioxins such as what they are, where they can be found, and major sources of dioxins. They also discuss possible effects of dioxin exposure in humans, include advice about consumption of food that might contain dioxins, and explain the review process for the dioxin reassessment.

History/Chronology

Oct 2004EPA released the NAS External Review Draft of the Dioxin Assessment, in preparation for the first NAS panel meeting (held 11/22 -23/2004), in Wash., DC. This is still the most current version of the EPA Dioxin Assessment.
Jul 2006NAS released Health Risks from Dioxin and Related Compounds: Evaluation of the EPA Reassessment.
Nov 2008EPA released a preliminary search list to address EPA's Reponses to the NAS comments on the 2003 Dioxin Reassessment report.
Feb 2009EPA hosted a 3-day public, scientific workshop to assist EPA in responding to the NAS reports on Dioxin. [ Workshop Announcement and details]
Jun 2009EPA released the Dioxin Workshop Summary report containing discussions and conclusions from the Feb 18-20, 2009 workshop held in Cincinnati, Ohio.
Feb 2010EPA initiated an interagency science consultation on the review of the draft document on EPA's Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments and charge for external peer reviewers.
May 2010EPA released to the public the Interagency Science Consultation draft Dioxin Reanalysis report and charge questions along with the External Peer Review draft Dioxin Reanalysis.

Next Steps

Following external peer review the assessment will be revised taking into consideration external peer review and public comments. It will then undergo a final EPA internal review and a review by other federal agencies and White House offices, followed by posting to the IRIS Web site.

Citation

U.S. EPA. EPA's Response to "Health Risks from Dioxin and Related Compounds Evaluation of the EPA Reassessment" Published By the National Research Council of the National Academies (Interagency Science Consultation Draft). U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-10/038C, 2010.

Recent Additions | Advanced Search | IRIS Home | NCEA Home | ORD Home


Local Navigation


Jump to main content.