[Federal Register Volume 73, Number 52 (Monday, March 17, 2008)]
[Notices]
[Page 14251]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E8-5242]


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DEPARTMENT OF HEALTH AND HUMAN SERVICES


National Toxicology Program (NTP); Center for the Evaluation of 
Risks to Human Reproduction (CERHR); Availability of the Draft NTP 
Brief on Hydroxyurea; Request for Public Comments

AGENCY: National Institute of Environmental Health Sciences (NIEHS); 
National Institutes of Health (NIH).

ACTION: Request for comments.

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SUMMARY: CERHR invites the submission of public comments on the draft 
NTP Brief for Hydroxyurea. The draft NTP Brief is available from the 
CERHR Web site (http://cerhr.niehs.nih.gov; see ``Hydroxyurea'' under 
``CERHR Reports & Monographs'') or in hardcopy from CERHR (see 
ADDRESSES below). Public comments will be considered during the peer 
review and finalization of the NTP Brief.

DATES: Written comments on the draft NTP Brief for Hydroxyurea should 
be received by May 1, 2008.

ADDRESSES: Public comments and any other correspondence should be 
addressed to Dr. Michael D. Shelby, CERHR Director, NIEHS, P.O. Box 
12233, MD EC-32, Research Triangle Park, NC 27709 (mail), (919) 541-
3455 (phone), (919) 316-4511 (fax), or [email protected] (e-mail). 
Courier address: CERHR, 79 T.W. Alexander Drive, Building 4401, Room 
103, Research Triangle Park, NC 27709.

SUPPLEMENTARY INFORMATION: 

Background

    Hydroxyurea is used in the treatment of cancer, sickle cell 
disease, and thalassemia. It is the only treatment for sickle cell 
disease used in children, aside from blood transfusion and, in severe 
cases, bone marrow transplantation. Hydroxyurea may be used in the 
treatment of children and adults with sickle cell disease for an 
extended period of time or for repeated cycles of therapy. Treatment 
with hydroxyurea may be associated with cytotoxic and myelosuppressive 
effects and hydroxyurea is mutagenic. Hydroxyurea is FDA-approved for 
use in adults with sickle cell anemia to reduce the frequency of 
moderate to severe painful crises and the need for blood transfusions. 
CERHR selected hydroxyurea for evaluation because of: (1) Increasing 
use in the treatment of sickle cell disease in children and adults, (2) 
knowledge that it inhibits DNA synthesis and is cytotoxic, and (3) 
published evidence of reproductive and developmental toxicity in 
rodents. On January 24-26, 2007, CERHR convened an expert panel to 
conduct an evaluation of the potential reproductive and developmental 
toxicities of hydroxyurea. The expert panel report was released for 
public comment on February 26, 2007 (Federal Register Vol. 72, No. 37, 
pp. 8384-8385). Following this public comment period, CERHR staff 
prepared the draft NTP Brief for Hydroxyurea that provides in plain 
language:
     Background information on the substance(s).
     Findings of the expert panel.
     Discussion of any relevant data available after the expert 
panel meeting.
     NTP's conclusions on the potential for the substance to 
cause adverse reproductive and/or developmental effects in exposed 
humans.
    Upon finalization, the NTP Brief for Hydroxyurea will be included 
in the CERHR Monograph for Hydroxyurea. The draft NTP Brief for 
Hydroxyurea and related background materials, including the hydroxyurea 
expert panel report and previously received public comments, are 
available on the CERHR Web site (http://cerhr.niehs.nih.gov; see 
``Hydroxyurea'' under ``CERHR Reports & Monographs'').

Request for Comments

    The NTP invites written public comments on the draft NTP Brief for 
Hydroxyurea. Any comments received will be posted on the CERHR Web site 
and considered during the peer review and finalization of the NTP Brief 
for Hydroxyurea. Persons submitting written comments are asked to 
include their name and contact information (affiliation, mailing 
address, telephone and facsimile numbers, e-mail, and sponsoring 
organization, if any) and submit comments to Dr. Shelby (see ADDRESSES 
above) for receipt by May 1, 2008.

Background Information on CERHR

    The NTP established CERHR in June 1998 (Federal Register Vol. 63, 
No. 239, p. 68782). CERHR is a publicly accessible resource for 
information about adverse reproductive and/or developmental health 
effects associated with exposure to environmental and/or occupational 
exposures.
    CERHR invites the nomination of agents for review or scientists for 
its expert registry. Information about CERHR and the nomination process 
can be obtained from its homepage (http://cerhr.niehs.nih.gov) or by 
contacting Dr. Michael Shelby, CERHR Director (see ADDRESSES). CERHR 
selects chemicals for evaluation based upon several factors including 
production volume, potential for human exposure from use and occurrence 
in the environment, extent of public concern, and extent of data from 
reproductive and developmental toxicity studies. Expert panels conduct 
scientific evaluations of agents selected by CERHR in public forums. 
Following these evaluations, CERHR prepares the NTP-CERHR monograph on 
the agent evaluated. The monograph is transmitted to appropriate 
federal and state agencies and made available to the public.

    Dated: March 6, 2008.
Samuel H. Wilson,
Acting Director, National Institute of Environmental Health Sciences 
and National Toxicology Program.
[FR Doc. E8-5242 Filed 3-14-08; 8:45 am]
BILLING CODE 4140-01-P