National Toxicology Program

National Toxicology Program

Nominations in Review 2011

Substances studied by NTP are selected primarily on the basis of production levels, known or anticipated human exposure, suspicion of toxicity based on chemical structure or existing health effects data, availability of adequate toxicological data, and the extent of public concern. Selection of a substance for study does not imply that the substance is hazardous to humans or toxic/carcinogenic to laboratory animals. Likewise, when nominated substances are not selected for toxicological evaluation by NTP, this should not be taken to mean that the substance is not a potential human health hazard. Nominated substances in the table below are identified by a common or generic name and CASRN where appropriate.

Learn more about NTP study types.

For information, questions or comments, contact:

Dr. Scott A. Masten
Director, Office of Nomination and Selection
Division of the National Toxicology Program
National Institute of Environmental Health Sciences

P.O. Box 12233, MD K2-02
Research Triangle Park, NC 27709
(919) 541-5710 (voice)
(301) 451-5599 (fax)

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[CAS No.]
Nomination Source Nomination Rationale* Proposed Studies**
Octrizole [3147-75-9] and related phenolic benzotriazoles
Nomination support document(s)
Draft Research Concept
NIEHS High production volume and use as UV stabilizers in a wide variety of industrial and consumer products; possess physico-chemical properties that suggest persistence in the environment and potential to bioaccumulate; limited toxicological data yet reproductive and developmental effects data for several class members suggest potential hazard
  • Short-term in vivo and in vitro toxicity studies on multiple (10 or more) class members to prioritize individual compounds for further study
  • For one or more selected class members:
  • ADME and toxicokinetics studies by oral and dermal routes of administration
  • Reproductive and developmental toxicity studies
  • Subchronic toxicity studies
  • Chronic toxicity and carcinogenicity studies, if warranted based on above
Nomination support document(s)
Draft Research Concept
Fairbanks North Star Borough Mayor
Alaska Department of Health and Social Services
Alaska State Senator John Coghill
National Center for Environmental Health / Agency for Toxic Substances and Disease Registry
High production volume and use in oil and gas refining; public concern related to groundwater contamination in Alaska; inadequate data to evaluate potential adverse health effects from long-term exposures
  • Short-term oral toxicity studies to evaluate species sensitivity
  • ADME and toxicokinetics studies by multiple routes of administration
  • Perinatal exposure studies to evaluate reproductive and developmental toxicity, immune toxicity, and developmental neurotoxicity
  • Chronic toxicity and carcinogenicity studies
Nomination support document(s)
Draft Research Concept
Occupational Safety and Health Administration
Low volume production and use as a reagent in synthetic and analytical chemistry; developed and promoted as a safer substitute for diazomethane; inadequate toxicological data; case reports of severe lung injury and death in exposed laboratory personnel
  • Chemistry studies to evaluate stability and reactivity
  • Acute inhalation toxicity studies
*The rationale for the nomination is provided by the nominator and is summarized here to be consistent with the NTP Nomination Principles and the selection factors stated above.
**Recommendations for proposed studies are initially developed by NTP staff based on needs identified by the nominator and review of all relevant information. Study recommendations are further refined based on comments received during interagency and Board of Scientific Counselors review of the nomination and draft research concept. Additional detail on proposed studies is included in the draft research concept documents.

Note: Some documents on this page may not be fully accessible to some readers. If you have difficulty accessing a document, email the NTP Webmaster or call Dr. Scott Masten at 919-541-5710 and identify documents/pages for which access is required.

NTP is located at the National Institute of Environmental Health Sciences, part of the National Institutes of Health.