E9-21194. Notice of Availability of the External Peer Review Draft of Recommended Toxicity Equivalency Factors (TEFs) for Human Health Risk Assessments of Dioxin and Dioxin-Like Compounds

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Notice of document availability for public comment.

SUMMARY:

The Environmental Protection Agency (EPA) is announcing a 30-day public comment period for the external peer review draft of “Recommended Toxicity Equivalency Factors (TEFs) for Human Health Risk Assessments of Dioxin and Dioxin-Like Compounds,” a draft guidance document. An EPA contractor for external peer review will convene a panel of experts and will organize and conduct an independent expert external peer review meeting to review the draft document. All comments received by the closing date of October 2, 2009 will be shared with the external peer review panel for their consideration. Comments received after the close of the comment period may be considered by EPA when it finalizes the document. This draft guidance document does not represent and should not be construed to represent any EPA policy, viewpoint, or determination. Members of the public may obtain the draft document from http://www.regulations.gov; or http://www.epa.gov/​raf/​hhtefguidance;​; or from Seema Schappelle via the contact information below. The public comment period and external peer review are separate processes that provide opportunities for all interested parties to comment on the document.

The external expert peer review will be conducted by letter and open teleconference in the fall 2009 time frame. The panel may consider public comments received in the official public docket for this activity under docket ID number EPA-HQ-ORD-2009-0605. The draft document is available at http://www.epa.gov/​raf/​hhtefguidance. In preparing a final document, EPA intends to consider the public comments submitted to EPA's docket during the public comment period and the comments and recommendations from the external peer reviewers.

EPA is releasing this draft document solely for the purpose of pre-dissemination peer review under applicable information quality guidelines. This document has not been formally disseminated by the EPA. It does not represent and should not be construed to represent any Agency policy or determination.

DATES:

All comments received by October 2, 2009 will be shared with the external peer review panel for their consideration. Comments received beyond that time may be considered by EPA when it finalizes the documents.

ADDRESSES:

The draft document is available electronically through the EPA Office of the Science Advisor's Web site at: http://www.epa.gov/​raf/​hhtefguidance.

Submit your comments, identified by Docket ID No. EPA-HQ-ORD-2009-0605, by one of the following methods:

• Online at: http://www.regulations.gov; Follow the on-line instructions for submitting comments.
• E-mail: [e-mail].
• Mail: ORD Docket, Environmental Protection Agency, Mailcode: 28221T, 1200 Pennsylvania Avenue, NW., Washington, DC 20460.
• Hand Delivery: EPA Docket Center (EPA/DC), Room 3334, EPA West Building, 1301 Constitution Avenue, NW., Washington, DC 20460, Attention Docket ID No. EPA-HQ-ORD-2009-0605. Deliveries are only accepted from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. Special arrangements should be made for deliveries of boxed information.

Instructions: Direct your comments to Docket ID No. EPA-HQ-ORD-2009-0605. Please ensure that your comments are submitted within the specified comment period. Comments received after the closing date will be marked “late” and may only be considered if time permits. EPA's policy is that all comments received will be included in the public docket without change. These may be made available online at http://www.regulations.gov, including any personal information provided, unless the comment includes information claimed to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Do not submit information that you consider to be CBI or otherwise protected by statute through http://www.regulations.gov or e-mail.

The http://www.regulations.gov Web site is an “anonymous access” system, which means EPA will not know your identity or contact information unless you provide it in the body of your comment. If you send an e-mail comment directly to EPA, without going through http://www.regulations.gov, your e-mail address will be automatically captured and included as part of the comment that is placed in the public docket and made available on the Internet. If you submit an electronic comment, EPA recommends that you include your name and other contact information in the body of your comment and with any disk or CD-ROM you submit. If EPA cannot read your comment due to technical difficulties and cannot contact you for clarification, EPA may not be able to consider your comment. Electronic files should avoid the use of special characters, any form of encryption, and be free of any defects or viruses. For additional information about EPA's public docket, visit the EPA Docket Center's homepage at http://www.epa.gov/​epahome/​dockets.htm.

Docket: All documents in the docket are listed in the http://www.regulations.gov index. Although listed in the index, some information is not publicly available, e.g., CBI or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, will be publicly available only in hard copy.

Publicly available docket materials are available either electronically in http://www.regulations.gov or in hard copy at the EPA Docket Center (EPA/DC), Room 3334, EPA West Building, 1301 Constitution Avenue, NW., Washington, DC 20460. The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The telephone number for the Public Reading Room is [phone], and the telephone number for the ORD Docket is [phone].

FOR FURTHER INFORMATION CONTACT:

Seema Schappelle, Risk Assessment Forum, Mail Code 8105R, Environmental Protection Agency, 1200 Pennsylvania Avenue, NW., Washington, DC 20460; telephone number: [phone]; fax number: [phone], E-mail: [e-mail].

SUPPLEMENTARY INFORMATION:

Dioxin and dioxin like compounds (DLCs), including polychlorinated dibenzo-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs), are structurally and toxicologically related halogenated dicyclic aromatic hydrocarbons. Dioxins and DLCs are released into the environment from several industrial sources, including chemical manufacturing, combustion, and metal processing. There is global contamination of air, soil and water with trace levels of these compounds that typically occur in the environment as chemical mixtures. Dioxins and DLCs do not readily degrade; therefore, levels persist in the environment, build up in the food chain and accumulate in the tissues of animals. Human exposures to these compounds occur primarily through eating contaminated foods. The health effects from exposures to dioxins and DLCs have been documented extensively in toxicological and epidemiological studies.

Risk assessments have relied on the dioxin toxicity equivalence factors (TEFs) approach. Various stakeholders, inside and outside the Agency, have called for a more comprehensive characterization of risks; therefore, EPA's Risk Assessment Forum (RAF), located in the Office of the Science Advisor, identified a need to examine the recommended approach for application of the toxicity equivalence methodology in human health risk assessments. An RAF Technical Panel developed the draft guidance document, “Recommended Toxicity Equivalency Factors (TEFs) for Human Health Risk Assessments of Dioxin and Dioxin-Like Compounds,” to assist EPA scientists in using this methodology to assess health risks from dioxins and dioxin-like compounds, as well as inform EPA decision makers, other agencies, and the public about this methodology. EPA is currently addressing several issues related to dioxins and dioxin-like chemicals in the environment. More information on these activities is located at: http://cfpub.epa.gov/​ncea/​CFM/​nceaQFind.cfm?​keyword=​Dioxin.

Dated: August 26, 2009.

Kevin Teichman,

Acting EPA Science Advisor.