National Toxicology Program

[Federal Register: August 5, 1999 (Volume 64, Number 150)]
[Notices]
[Page 42707-42708]

PUBLIC HEALTH SERVICE

National Toxicology Program, National Institute of Environmental Health Sciences, Center for the Evaluation of Risks to Human Reproduction; Announces an Expert Panel Review of Phthalates, August 17-19, 1999 in Alexandria, VA.

Background

The National Toxicology Program (NTP) and the National Institute of Environmental Health Sciences have established the NTP Center for the Evaluation of Risks to Human Reproduction (63 FR 68782, No 239). The purpose of the Center is to provide timely and

unbiased, scientifically sound evaluations of human and experimental evidence for adverse effects on reproduction, including development, caused by agents to which humans may be exposed. The evaluations produced through the Center will be published as monographs in Environmental Health Perspectives; a special effort will be made to summarize the reports in terms that can be understood by those who are not scientifically trained.

Expert Panel Review of Phthalates

Seven phthalate esters will be evaluated by an expert panel under the auspices of the NTP Center (64 FR 18921-18922, No 73). These were selected based on their high production volume, extent of human exposures, use in children's products, or published evidence of reproductive or developmental toxicity. The chemicals to be evaluated are listed below with their Chemical Abstract Service registry numbers.

butyl benzyl phthalate (85-68-7)
di(2-ethylhexyl) phthalate (117-81-7)
di-isodecyl phthalate (26761-40-0, 68515-49-1)
di-isononyl phthalate (28553-12-0, 68515-48-0)
di-n-butyl phthalate (84-74-2)
di-n-hexyl phthalate (84-75-3)
di-n-octyl phthalate (117-84-0)

Review Panel and Charge to Panel

To date, a panel of 14 scientists have been selected for their expertise in various aspects of reproductive toxicology and other relevant areas to conduct the review. The roster of these experts follows:

Phthalates Expert Panel

Charge to Expert Panel

Rigorously evaluate all relevant data and reach a conclusion regarding the strength of scientific evidence that exposure to a chemical may or may not present a risk to human reproduction or development.

1. Evaluate all reproductive and developmental toxicity studies - in humans and animals - for quality, completeness, and sufficiency. Determine consistency of reported effects within and among species. Briefly summarize relevant individual studies.

2. Review and summarize related studies paying particular attention to studies of general toxicity, pharmacokinetics, genetic toxicity, and mechanisms of toxicity, within and across species. Both in vivo and in vitro studies will be included.

3. Determine, to the extent possible, patterns of use (such as timing, duration) and exposure (such as dose, route) to humans.

4. Integrate this information, using a weight of evidence approach. Determine how human, animal and other data can reasonably be used to predict reproductive or developmental effects in humans under particular exposure conditions.

5. Provide judgments, including qualitative statements of the certainty of the judgments, that an agent presents a potential risk to human reproduction and/or development. Describe the major factors that contributed to these judgments. State the exposure circumstances under which such risk might be expected to exist.

6. Identify specific areas of uncertainty (such as inadequate pharmacokinetic data in a given species) that would prevent a more definitive assessment of human risk.

7. Identify research and testing needs that, if met, would significantly reduce the uncertainty inherent in the stated judgments of risk.

Meeting Open to the Public

The preliminary agenda for the panel meeting follows:

August 17 (beginning at 8:30 a.m.)

Opening remarks by Dr. Michael Shelby, NIEHS and Director of the Center, Dr. George Lucier, Director of the NIEHS’ Environmental Toxicology Program, and Dr. Robert Kavlock, EPA, and Chair of the Expert Panel.

Panel members will present summaries of the literature they will have individually reviewed in advance of the meeting.

The Phthalate Esters Panel of the Chemical Manufacturers Association, Health Care Without Harm, and the American Council on Science and Health will summarize the deliberations of their recent literature reviews of the possible reproductive and developmental health risks of phthalate exposures.

Panel discussion will follow to identify areas where there is broad panel agreement as well as issues requiring further discussion by workgroups of the panel.

Time will be available to members of the public for comment.

August 17 (PM) -18-19

The remainder of the meeting will be an iterative series of workgroup discussions and plenary sessions. Significant conclusions and judgments reached by the panel workgroups will be presented, discussed, and agreed to by the entire expert panel in plenary sessions. Definitive judgments will be made for each of the seven phthalates.

August 19, 11:00 a.m. (tentatively)

Closing plenary session, review of panel conclusions.

The review will take place from August 17-19 at the Embassy Suites Hotel, 1900 Diagonal Road, Alexandria, VA with some workgroup sessions at Sciences, International, Inc., 1800 Diagonal Road, Suite 500, Alexandria, VA (limited seating availability). The meeting will commence at 8:30 AM on August 17 in the Virginia Ballroom of the Embassy Suites Hotel.

The review will be open to the public with an opportunity scheduled for oral public comment. Attendance will be limited only by the availability of space. For registration information please contact: Ms. Peggy Sheren, CERHR, 1800 Diagonal Road, Suite 500, Alexandria, VA 22314-2808, Phone: (703) 838-9440.

Dated: July 28, 1999



______________________
Samuel H. Wilson, M.D.
Deputy Director, NIEHS

[Billing Code 4140-01-P]