An official website of the United States government
The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.
The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.
Nominated Substances: Silica, crystalline - quartz
Nomination Date: 04/11/1994
Nominator: Private Individual
Rationale: To establish whether the carcinogenic risk of crystalline silica is because it is a traditional carcinogen that interacts with nuclear macromolecules or because of an epigenetic process associated with cell damage and healing.
NTP Principles: not specified