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Draft EPA's Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments (EPA/600/R-10/038A)

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Information about this document as published in the Federal Register.

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Environmental Protection Agency (EPA).


Notice of Listening Session.


EPA is announcing a listening session to be held on July 9, 2010, during the public comment period for the external review draft document entitled “EPA's Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments” (EPA/600/R-10/038A). The EPA's draft document and peer review charge are available via the Internet on the National Center for Environmental Assessment's (NCEA) home page under the Recent Additions and Publications menus at​ncea. This draft document responds to the key recommendations and comments included in the National Academy of Sciences (NAS) 2006 report. In addition, it includes new analyses on potential human effects that may result from exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).

The release of the draft document for public comment was announced in a May 21, 2010, Federal Register Notice (75 FR 28610). EPA also announced that it intends to forward all public comments submitted before July 7, 2010, in response to the May 21, 2010, Notice, to the EPA Science Advisory Board (SAB) peer review panel for its consideration and provided instructions for submitting comments.

The draft document is also being provided to the SAB, a body established under the Federal Advisory Committee Act, for independent external peer review. The SAB is convening an expert panel composed of scientists knowledgeable about technical issues related to dioxins and risk assessment. The SAB is holding a public teleconference on June 24, 2010, and a public panel meeting on July 13-15, 2010. The SAB peer review meetings were announced by the SAB staff office in a separate May 24, 2010, Federal Register Notice (75 FR 28805). Members of the public who wish to ensure that their technical comments are provided to the SAB expert panel before each meeting should also e-mail their comments separately to Thomas Armitage, the SAB Designated Federal Officer at, following the procedures in the May 24, 2010, Federal Register Notice announcing the SAB public meetings. The public comment period and SAB external peer review are independent processes that provide separate opportunities for all interested parties to comment on the draft report.

The purpose of the listening session is to allow all interested parties to present scientific and technical comments on draft IRIS health assessments to EPA and other interested parties during the public comment period and before the external peer review meeting. EPA welcomes the scientific and technical comments that will be provided to the Agency by the listening session participants. All comments submitted according to the detailed instructions provided in the May 21, 2010, Federal Register Notice under SUPPLEMENTARY INFORMATION will be considered by the Agency as it revises the draft assessment in response to the independent external peer review and public comments. All presentations will become part of the official public record.


The listening session on the draft IRIS health assessment for dioxin will be held on July 9, 2010, beginning at 9 a.m. and ending at 4 p.m., Eastern Daylight Time. If you would like to make a presentation at the listening session, you should register by July 2, 2010, indicate that you wish to make oral comments at the session, and indicate the length of your presentation. When you register, please indicate if you will need audio-visual equipment (e.g., laptop computer and slide projector). In general, each presentation should be no more than 30 minutes. If, however, there are more requests for presentations than the allotted time allows, then the time limit for each presentation will be adjusted. A copy of the agenda for the listening session will be available at the meeting. If no speakers have registered by July 2, 2010, the listening session will be cancelled and EPA will notify those registered of the cancellation.

The public comment period for review of this draft assessment was announced previously in the Federal Register (75 FR 28610) on May 21, 1010. As stated in that Federal Register Notice, the public comment period began on May 21, 2010, and ends August 19, 2010. Any technical comments submitted during the public comment period should be in writing and must be received by EPA by August 19, 2010, according to the procedures outlined in the May 21, 2010, Federal Register Notice. Only those public comments submitted by July 7, 2010, or e-mailed separately to Thomas Armitage, the SAB Designated Federal Officer at, following the procedures in the May 24, 2010, Federal Register Notice announcing the SAB public meetings, will be provided to the independent peer-review panel prior to the peer-review meeting. However, all comments received during the public comment period will be provided to the SAB peer review committee and will also inform the Agency's revision of the draft assessment.


The listening session on the draft dioxin assessment will be held at the EPA offices at Two Potomac Yard South Building, 4th Floor, S-4370-80, 2733 South Crystal Drive, Arlington, Virginia 22202. To attend the listening session, register by July 2, 2010. To present at the listening session, indicate in your registration that you want to make oral comments at the session and provide the length of your presentation. To register, send an e-mail to: (subject line: Dioxin Listening Session); call Christine Ross at 703-347-8592; or fax a registration request to 703-347-8689 (please reference the “Dioxin Listening Session” and include your name, title, affiliation, full address and contact information). Please note that to gain entrance to this EPA building to attend the meeting, attendees must have photo identification with them and must register at the guard's desk in the lobby. The guard will retain your photo identification and will provide you with a visitor's badge. At the guard's desk, attendees should give the name Christine Ross and the telephone number 703-347-8592 to the guard on duty. The guard will contact Ms. Ross who will meet you in the reception area to escort you to the meeting room. When you leave the building, please return your visitor's badge to the guard and you will receive your photo identification.

A teleconference line will also be available for registered attendees/speakers. The teleconference number is 866-299-3188, and the access code is 926-378-7897, followed by the pound sign (#). The teleconference line will be activated at 8:45 a.m., and you will be asked to identify yourself and your affiliation at the beginning of the call.Start Printed Page 33616

Information on Services for Individuals with Disabilities: EPA welcomes public attendance at the “Dioxin Listening Session” and will make every effort to accommodate persons with disabilities. For information on access or services for individuals with disabilities, please contact Christine Ross at 703-347-8592 or To request accommodation of a disability, please contact Ms. Ross, preferably at least 10 days prior to the meeting, to give EPA as much time as possible to process your request.

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For information on the public listening sessions, please contact Christine Ross, IRIS Staff, National Center for Environmental Assessment, (8601P), U.S. EPA, 1200 Pennsylvania Avenue, NW., Washington, DC 20460; telephone: 703-347-8592; facsimile: 703-347-8689; or e-mail: For questions about the draft dioxin assessment, contact Glenn Rice, National Center for Environmental Assessment, A110, U.S. EPA, 26 West Martin Luther King Drive, Cincinnati, OH 45268; telephone: 513-569-7813; facsimile: 513-487-2539 or e-mail:

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EPA's IRIS is a human health assessment program that evaluates quantitative and qualitative risk information on effects that may result from exposure to chemical substances found in the environment. Through the IRIS Program, EPA provides the highest quality science-based human health assessments to support the Agency's regulatory activities. The IRIS database contains information for more than 540 chemical substances that can be used to support the first two steps (hazard identification and dose-response evaluation) of the risk assessment process. When supported by available data, IRIS provides oral reference doses (RfDs) and inhalation reference concentrations (RfCs) for chronic noncancer health effects and cancer assessments. Combined with specific exposure information, government and private entities use IRIS to help characterize public health risks of chemical substances in a site-specific situation and thereby support risk management decisions designed to protect public health.

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Dated: June 8, 2010.

Rebecca Clark,

Acting Director, National Center for Environmental Assessment.

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[FR Doc. 2010-14239 Filed 6-11-10; 8:45 am]