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Dioxin Science Plan (Issued 2009)

In 2009, EPA issued a plan with interim milestones to move forward two dioxin-related efforts:

  • EPA's comprehensive human health and exposure assessment for dioxin (commonly called the "dioxin reassessment"), and
  • EPA's review of dioxin soil clean-up levels currently in use across the United States.

See: EPA ’s Science Plan for Activities Related to Dioxins in the Environment Final, May 2009 (2 pp, 117K, About PDF)

EPA completed the following reports as a result of the dioxin science plan:​

Date Milestone

Feb 2012

EPA released the final Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments, Volume 1, and posted it to the IRIS database. This document provides hazard identification and dose-response information on 2,3,7,8- tetrachlorodibenzo-p-dioxin (TCDD) and includes a reference dose (RfD) for noncancer effects.

Aug 2011

The SAB released their final report reviewing EPA’s Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments.

Dec 2010

EPA’s final report Recommended Toxicity Equivalence Factors (TEFs) for Human Health Risk Assessments of 2,3,7,8-Tetrachlorodibenzo-p-dioxin and Dioxin-Like Compounds (December 2010) was released.

Jun 2010

EPA released a Draft Dioxin Reanalysis report for a 120-day public review and comment period as stated in the Dioxin Science Plan and announced in a May 21, 2010 Federal Register (FR) Notice, with the extension in a June 23, 2010 FR Notice.

May 2010

The draft response to comments report titled EPA’s Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments (External Review Draft) (“Draft Dioxin Reanalysis”) was completed and released for public review and comment on May 21, 2010.

Dec 2009

EPA's Draft Recommended Interim Preliminary Remediation Goals for Dioxin in Soil at CERCLA and RCRA Sites (December 2009) (Draft Report) was announced on December 30, 2009. Then on December 31, 2009, EPA’s Review of State Soil Cleanup Levels for Dioxin (December 2009) (Final Report) was provided to EPA’s Office of Land and Emergency Management (OLEM), formerly called the Office of Solid Waste and Emergency Response (OSWER), and posted to the EPA website.

Sep 2009

The EPA’s Review of the University of Michigan Dioxin Exposure Study (September 2009) was posted to the EPA website on September 30, 2009.

Jun 2009

EPA released the Dioxin Workshop Summary report containing discussions and conclusions from the Feb 18-20, 2009 workshop held in Cincinnati, Ohio.