Notice of Availability of Draft Reference Dose Document for Methylmercury

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Notice of availability of draft reference dose document for methylmercury.

SUMMARY:

Section 304(a)(1) of the Clean Water Act requires the Environmental Protection Agency to develop and publish, and from time to time revise, criteria for water to accurately reflect the latest scientific knowledge. EPA is revising its reference dose in support of a revised ambient water quality criterion for methylmercury. Today, EPA is notifying the public of the availability of the draft reference dose document and is also announcing that the draft document is ready for external scientific peer review.

EPA is notifying the public about the availability of this draft document and its peer review in accordance with the Agency's new process for developing or revising criteria (63 FR 68354, December 10, 1998). As indicated in the December 10, 1998 Federal Register document, the Agency believes it is important to provide the public with an opportunity to submit scientific information on draft criteria. EPA is soliciting views from the public on issues of science pertaining to the information used in deriving the draft reference dose.

DATES:

All significant scientific information must be submitted to the Agency under docket number W-00-29. All submissions of significant scientific information are requested to be submitted on or before December 14, 2000. Information submitted after this date may not receive the degree of consideration of information submitted earlier. The Administrative Record supporting this draft reference dose document is available at the Water Docket, Room EB-57, Environmental Protection Agency, 401 M Street SW., Washington, DC 20460 on Monday through Friday, excluding Federal holidays, between 9 a.m. and 4 p.m. For access to docket materials call (202) 260-3027 for an appointment. A reasonable fee will be charged for photocopies.

ADDRESSES:

Send an original and three copies of any written significant scientific information to W-00-15 Comment Clerk, Water Docket, Ariel Rios 1200 Pennsylvania Ave., NW., Washington, DC 20460. Comments may be hand-delivered to the Water Docket, Room EB57, 401 M Street, SW., Washington, DC 20460. Issues may also be submitted electronically to OW-Docket@epa.gov. Information should be submitted as a WP5.1, 6.1 and/or 8.0 or an ASCII file with no form of encryption.

Copies of the draft reference dose document entitled, Reference Dose for Methylmercury, may be obtained from EPA's Water Resource Center by phone at (202) 260-7786, or by e-mail to center.water-resource@epa.gov or by conventional mail to EPA Water Resource Center, RC-4100, 401 M Street SW., Washington, DC 20460. Alternatively, consult www.epa.gov/ost/criteria/methylmercury/ for download availability.

FOR FURTHER INFORMATION CONTACT:

Ms. Mary Manibusan, Health and Ecological Criteria Division (4304), US EPA, Ariel Rios Building, 1200 Pennsylvania Avenue NW., Washington, DC 20460; (202) 260-3688; manibusan.mary@epa.gov

SUPPLEMENTARY INFORMATION:

What Is a Reference Dose?

The reference dose is defined as an estimate, with uncertainty spanning perhaps one order of magnitude, of a daily exposure to the human population (including sensitive subgroups) that is likely to be without an appreciable level of risk of deleterious effects during a lifetime. The RfD is useful as a reference point from which to gauge the potential effects of the chemical at other doses. Usually, doses less than the RfD are not likely to be associated with adverse health risks and are, therefore, less likely to be of regulatory concern. As the frequency and/or magnitude of the exposures exceeding the RfD increase, the probability of adverse effects in a human population increases. However, it should not be categorically concluded that all doses below the RfD are “acceptable” or risk-free and that all doses in excess of the RfD are “unacceptable” or will result in adverse effects.

Why Is EPA Notifying the Public About the Draft Reference Dose Document and Peer Review?

Today, in order to expand the public's involvement in the criteria development process, EPA is notifying the public about the availability of the draft reference dose document for methylmercury and its peer review.

In following the Agency's new process, EPA notified the public of its intentions to revise the ambient water quality criteria in the Federal Register on October 12, 2000 (65 FR 60664). At that time EPA made available to the public a list of all references identified by a recent literature review and solicited any additional pertinent data or scientific views that would be useful in revising the ambient water quality criteria. EPA is revising the ambient water quality criteria for methylmercury based on new data and new analyses. The draft reference dose document to support the ambient water quality criterion is ready for external scientific peer review.

As indicated in the December 10, 1998 Federal Register document, the Agency believes it is important to provide the public with an opportunity to submit scientific information on draft criteria. EPA is soliciting views from the public on issues of science pertaining to the information used in deriving the draft reference dose. EPA will review and consider significant scientific information submitted by the public that might not have otherwise been identified during development of this criterion.