[Federal Register Volume 64, Number 63 (Friday, April 2, 1999)]
[Notices]
[Pages 15983-15984]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-8098]


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DEPARTMENT OF HEALTH AND HUMAN SERVICES

Public Health Service


National Toxicology Program: Call for Public Comment on 11 
Substances, Mixtures and Exposure Circumstances To Be Reviewed in 1999 
for Listing in or Delisting (Removing) From the Report on Carcinogens, 
Tenth Edition

Background

    The National Toxicology Program (NTP) announces its intent to 
review additional substances, mixtures and exposure circumstances for 
possible listing in or delisting (removing) from the Report on 
Carcinogens, Tenth Edition which is scheduled for publication in 2001. 
This Report (previously known as the Annual Report on Carcinogens) is a 
Congressionally-directed listing of known human carcinogens and 
reasonable anticipated human carcinogens and its preparation is 
delegated to the National Toxicology Program by the Secretary, 
Department of Health and Human Services (DHHS). Section 301(b)(4) of 
the Public Health Service Act, as amended, provides that the Secretary, 
(DHHS), shall publish a report which contains a list of all substances 
(1) which either are known to be a human carcinogen or reasonable 
anticipated to be a human carcinogen, and (2) to which a significant 
number of persons residing in the United States (US) are exposed. The 
law also states that the reports should provide available information 
on the nature of exposures, the estimated number of persons exposed and 
the extent to which the implementation of Federal regulations decreases 
the risk to public health from exposure to these chemicals.
    The scientific review of the substances, mixtures or exposure 
circumstances involves three separate reviews, which include two 
Federal review groups and one non-government peer review body (a 
subcommittee of the NTP Board of Scientific Counselors) which will meet 
in an open, public meeting and provide for public comments. All 
available data and public comments received that are relevant to the 
application of the criteria for inclusion or removal of candidate 
agents, substances, mixtures or exposure circumstances or for a change 
in the classification in the Report will be evaluated. The criteria to 
be used in the review process are described below:

    1. Known to be Human Carcinogens:
    There is sufficient evidence of carcinogenicity from studies in 
humans which indicates a causal relationship between exposure to the 
agent, substance or mixture and human cancer.
    2. Reasonably Anticipated to be Human Carcinogens:
    There is limited evidence of carcinogenicity from studies in 
humans which indicates that causal interpretation is credible but 
that alternative explanations such as chance, bias or confounding 
factors could not adequately be excluded; or
    There is sufficient evidence of carcinogenicity from studies in 
experimental animals which indicates there is an increased incidence 
of malignant and/or a combination of malignant and benign tumors: 
(1) In multiple species, or at multiple tissue sites, or (2) by 
multiple routes of exposure, or (3) to an unusual degree with regard 
to incidence, site or type of tumor or age at onset; or
    There is less than sufficient evidence of carcinogenicity in 
humans or laboratory animals, however; the agent, substance or 
mixture belongs to a well defined, structurally-related class of 
substances whose members are listed in a previous Report on 
Carcinogens as either a known to be human carcinogen, or reasonably 
anticipated to be human carcinogen or there is convincing relevant 
information that the agent acts through mechanisms indicating it 
would likely cause cancer in humans.
    Conclusions regarding carcinogenicity in humans or experimental 
animals are based on scientific judgment, with consideration given 
to all relevant information. Relevant information includes, but is 
not limited to dose response, route of exposure, chemical structure, 
metabolism, pharmacokinetics, sensitive sub populations, genetic 
effects, or other data relating to mechanism of action or factors 
that may be unique to a given substance. For example, there may be 
substances for which there is evidence of carcinogenicity in 
laboratory animals but there are compelling data indicating that the 
agent acts through mechanisms which do not operate in humans and 
would therefore not reasonably be anticipated to cause cancer in 
humans.

Clarification of the Criteria

    Some questions have arisen regarding information from studies 
involving humans and how this is applied to the listing of a substance 
determined to be a ``known human carcinogen''. The ``known human 
carcinogen'' category requires evidence from studies of humans. This 
can include traditional cancer epidemiology studies, data from clinical 
studies, and/or data derived from the study of tissues from humans 
exposed to the substance in question and useful for evaluating whether 
a relevant cancer mechanism is operating in people.

[[Page 15984]]

Public Comment Requested

    Nominations for the Report on Carcinogens to be reviewed in 1999 
are provided in the following table with their Chemical Abstracts 
Services (CAS) Registry numbers (where available) and pending review 
action. NTP invites public comment on any of these nominations. In 
addition, NTP requests relevant information on the carcinogenic 
properties of the substances from completed or ongoing experimental 
animal or human epidemiology studies, as well as current production 
data, use patterns, and human exposure information. Comments received 
by April 30, 1999 will allow the time for their consideration by the 
initial review groups and by the NTP in the preparation of the 
background document prepared for each substance. Comments or questions 
should be directed to Dr. C. W. Jameson at the address listed below.

Public Nominations for Delisting or Listing Encouraged

    The NTP solicits and encourages the broadest participation form 
interested individuals or parties in nominating agents, substances, 
mixtures or exposure circumstances for listing in or delisting from the 
Reports on Carcinogens. Nominations from the public should contain a 
rationale for listing or delisting. Appropriate background information 
and relevant data (e.g. Journal articles, NTP Technical Reports, IARC 
listings, exposure surveys, release inventories, etc.) which support a 
nomination should be provided or referenced when possible.
    A detailed description of the review procedures, including the 
steps in the formal review process, is available at http://ntp-
server.niehs.nih.gov and can be obtained by contacting: Dr. C. W. 
Jameson, National Toxicology Program, Report on Carcinogens, MD EC-14, 
P.O. Box 12233, Research Triangle Park, NC 27709; phone: (919) 541-
4096, fax: (919) 541-0947, email: [email protected].

    Dated: March 22, 1999.
Kenneth Olden,
Director, National Toxicology Program.

 Summary for Agents, Substances, Mixtures or Exposure Circumstances to be Reviewed in 1999, for Consideration of
                          Listing in or Delisting from the Tenth Report on Carcinogens
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 Nomination to be reviewed/CAS No.    Primary uses or exposures                 To be reviewed for
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Beryllium and Beryllium Compounds/   Fiber optics and cellular   Possible updating of current listing of
 7440-41-7.                           network communications      beryllium and certain beryllium compounds to a
                                      systems, aerospace,         known human carcinogen.
                                      defense and other
                                      industry applications.
2,2-bis-(bromomethyl) -1,3-          Used as a fire retardant    Listing in the 10th Report.
 propanediol/3296-90-9.               in unsaturated polyester
                                      resins, in molded
                                      products, and in rigid
                                      polyurethane foam.
2,3-Dibromo-1-Propanol/96-13-9.....  Used as a flame retardant,  Listing in the 10th Report.
                                      as an intermediate in the
                                      preparation of the flame
                                      retardant tris(2,3-
                                      dibromopropyl) phosphate,
                                      and as an intermediate in
                                      the manufacture of
                                      pesticides and
                                      pharmaceutical
                                      preparations.
Dyes Metabolized to                  Dyes widely used for        Listing in the 10th Report.
 Dimethoxybenzidine                   leather, paper, plastics,
 (Dimethoxybenzidine Dyes as a        rubber, and textile
 Class).                              industries.
Dyes Metabolized to                  Dyes widely used for        Listing in the 10th Report.
 Dimethoxybenzidine                   leather, paper, plastics,
 (Dimethoxybenzidine Dyes as a        rubber, and textile
 Class).                              industries.
IQ (2-Amino-3-methylimidazo[4,5-     Found in cooked meat and    Listing in the 10th Report.
 f]quinoline)/76180-96-6.             fish.
Styrene=7,8=oxide/96-09-3..........  Used mainly in the          Listing in the 10th Report.
                                      preparation of fragrances
                                      and in some epoxy resin
                                      formulations.
Toluene Diisocyanate/26471-62-5....  Commercially produced as    Delisting from the Report on Carcinogens.
                                      an approximately 80:20
                                      mixture of the 2,4- and
                                      2,6-isomers it is
                                      primarily for use in the
                                      manufacture of flexible
                                      polyurethane foams.
UV Radiation/separate consideration  Soloar and artifical        Listing in the 10th Report.
 of three segments of the             sources of ultraviolet
 wavelength spectrum; UVA (315-400    radiation.
 nm), UVB (280-315 nm), and UVC
 (100-280 nm).
Vinyl Bromide/593-60-2.............  Used commercial since       Listing in the 10th Report.
                                      1968, primarily in the
                                      manufacture of flame
                                      retardant synthetic
                                      fibers.
Vinyl Fluoride/75-02-5.............  Used commercially since     Listing in the 10th Report.
                                      the 1960's, in the
                                      production of
                                      polyvinylfuoride which is
                                      used for plastics.
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[FR Doc. 99-8098 Filed 4-1-99; 8:45 am]
BILLING CODE 4140-01-M