Skip to Main Navigation
Skip to Page Content
U.S. flag

An official website of the United States government

Dot gov

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.

Nomination Summary for Ethinyl estradiol and/or mestranol (N91003)

Nominated Substances: Ethinyl estradiol, Ethinyl estradiol 3-methyl ether

Nomination Date: 03/11/1991

Nominator: Private Individual

Rationale: Use of oral contraceptive steroids has been associated with increased incidences of liver neoplasms in women. These compounds cause rapid increases in liver DNA synthesis at doses which are nearly equivalent to human doses. In many studies these compounds were concluded to be promoters of hepatocarcinogenesis. IARC monograph (Vol. 21) includes reviews of animal carcinogenicity studies on these compounds, but does not provide full information of strains of animals used, doses, or survival within individual dose groups.

NTP Principles: not specified

Agents and Status

The following information relates to the specific agent and may include history from earlier or later nominations for this same agent.

CASRN: 57-63-6

Agent Name: Ethinyl estradiol