National Toxicology Program

National Toxicology Program

Narrative describing RoC Schematic

The schematic shows the listing criteria and the review process.

Listing Criteria

3rd–7th RoC (1982) - 7th (1994)

Formal listing criteria: Criteria for two listing categories (known and reasonably anticipated to be a human carcinogen) based on evaluation of cancer studies in humans and experimental animals.

8th RoC (1998) - Present

Criteria expanded to include consideration of all relevant information such as mechanistic data. Approved by the Secretary, HHS in 1996



Review Process

2nd–4th RoC (1981) – 4th (1985)

No formal review process: Collaborative effort by NTP and its interagency partners.

5th RoC (1989) –7th RoC (1994)

Formal review process established

  • Two federal scientific review committees established: NIEHS/NTP Scientific Review Committee and Interagency Scientific Review Committee
  • NTP Executive Committee review added

8th RoC (1998) –11th RoC (2004)

External scientific and public inputs added:

  • NTP Board of Scientific Counselors (BSC) RoC Subcommitee established: External review in a public forum
  • Formal process for delisting a substance from the RoC
  • Opportunities for additional public input throughout the process

12th RoC (2011)

Process revised to:

  • NTP BSC RoC Subcommitee ended
  • Ad hoc expert panel convened in public forum: Input on listing recommendation and peer review of draft background document
  • NTP BSC: Peer review of substance profile in public forum

13th RoC (2014) - Present

Process revised to:

  • NTP develops a concept document for each proposed candidate substance that is shared with public and reviewed by the NTP BSC in a public forum
  • NTP prepares a RoC monograph for each substance that includes the cancer hazard evaluation, listing recommendtaion and the substance profile
  • Ad hoc review panel conducts external peer review of each RoC draft monograph in a public forum
NTP is located at the National Institute of Environmental Health Sciences, part of the National Institutes of Health.