EPA Asked To Delay Dioxin Assessment

The American Chemistry Council, a chemical industry group, is asking the Environmental Protection Agency to change course on its assessment of the most potent form of dioxin. Such a move could further prolong completion of the assessment, which has been under way for more than 20 years.

In a Dec. 20, 2011, letter, ACC asked EPA to delay the release of its hazard assessment for 2,3,7,8-tetrachloro­dibenzo-p-dioxin (TCDD). This pollutant causes cancer and is linked to reproductive problems. The assessment will affect the extent of cleanups of chlorinated and brominated dioxins and furans and polychlorinated biphenyls, as well as the costs borne by polluters.

Before EPA issues the assessment, ACC says, the agency should explain how the TCDD document hews to recent recommendations by the National Research Council.

NRC offered suggestions to improve EPA’s chemical assessments as part of a report criticizing the agency’s draft document on formaldehyde’s hazards (C&EN, April 18, 2011, page 10). EPA began implementing NRC’s recommendations last year (C&EN, July 18, 2011, page 9).

ACC is using language in a new appropriations bill to justify its request for a delay. Enacted in late December 2011, that legislation instructs EPA to document how it has implemented the NRC recommendations for each draft chemical assessment it releases in 2012.

In light of the new law, the letter from ACC President and CEO Calvin M. Dooley asks agency Administrator Lisa P. Jackson to reverse course on an EPA strategy to finish the long-pending document by splitting it into two parts (C&EN, Sept. 5, 2011, page 15). The agency plans to issue later this month a section on adverse noncancer health effects, such as reproductive problems, from exposure to TCDD. A second, more scientifically complicated part of the assessment will examine the cancer hazards of TCDD exposure and will be released later.

This bifurcated approach is counter to NRC’s recommendation that the agency’s chemical assessments evaluate all relevant health end points, Dooley argues.

The Center for Progressive Reform, a left-leaning think tank, says the law applies only to draft assessments, not the final TCDD document.

EPA says it is reviewing ACC’s request.