National Toxicology Program

Abstracts are taken from the published long-term toxicology and carcinogenesis study reports and include links to pathology tables, survival and growth curves; target organs and tumor incidences; 2-D and 3-D structures (to display the 3-D chemical structures, you will need the latest version of the free Chemscape Chime Plug-in) as well as links to the full report in pdf format. You may download a free copy of the reader from Adobe.

A link to the full report is listed at the end of each abstract. Reports may also be ordered from the National National Technical Information Service (NTIS) at URL: http://www.NTIS.gov or by phone at (703) 605-6000.

A "Compendium of Abstracts from Long-Term Cancer Studies Reported by the National Toxicology Program from 1976 to 1992" was published in Environmental Health Perspectives Supplements, Vol 101, Supplement 1, April 1993. This compendium is available from the NIEHS/NTP Central Data Management (CDM).

For more information, email Central Data Management, if you have your return mail address in your Web browser preferences, or contact:

Central Data Management
National Institute of Environmental Health Sciences
P.O. Box 12233
Mail Drop EC-03
Research Triangle Park, NC 27709

Telephone number: (919) 541-3419; FAX number: (919) 541-3687

The "Abstracts of NTP Long-Term Cancer Studies" is a complete collection of Technical Report Abstracts as taken from the published Technical Reports (TR) of the National Cancer Institute Bioassay Program (ca. 1971-1978) and it's successor, the National Toxicology Program. The exposure length for most of these was 2-years.

Long-term studies are conducted in compliance with Food and Drug Administration Good Laboratory Practice Regulations (21 CFR, Part 58). In addition, as records from the long-term studies are submitted to the NTP Archives, they are audited retrospectively by an independent quality assurance contractor. Separate audits covering completeness and accuracy of the pathology data, pathology specimens, final pathology tables, and preliminary review draft of NTP Technical Reports are conducted. Audit procedures and findings are presented in the reports and are on file at NIEHS. The audit findings are reviewed and assessed by NTP staff so that any discrepancies are resolved or otherwise addressed during the preparation of each Technical report.

For the long-term NTP toxicology and carcinogenesis studies, a Technical Reports Review Subcommittee, a standing subcommittee of the NTP Board of Scientific Counselors, provides peer review of the draft technical reports. This committee is supplemented as needed by an ad hoc Panel of Experts chosen primarily to encompass expertise in carcinogenesis, pathology, toxicology and biostatistics. The date and the list of chemical studies to be presented to the subcommittee are announced in the Federal Register; these reviews and discussions of the findings are open to the public.

These studies are designed and conducted to characterize and evaluate the toxicologic potention, including carcinogenic activity, of selected chemicals in laboratory animals (usually two species, rats and mice). Chemicals selected for NTP toxicology and carcinogenesis studies are chosen primarily on the bases of human exposure, level of production, and chemical structure. The interpretive conclusions presented in these Technical Reports are based only on the results of these NTP studies. Extrapolation of these results to other species and quantitative risk analyses for humans require wider analyses beyond the purview of these studies. Selection per se is not an indicator of a chemical's carcinogenic potential.

Definition of Carcinogenicity Results