Skip to Main Navigation
Skip to Page Content
COVID-19 is an emerging, rapidly evolving situation.

Get the latest public health information from CDC and research information from NIH.

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.

Https

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.

Share This:
https://ntp.niehs.nih.gov/go/8224

L-Tryptophan: Target Organs and Levels of Evidence for TR-071

Bioassay of L-Tryptophan for Possible Carcinogenicity (CASRN 73-22-3)

Chemical (Study Title)
CASRN		Peer Review DateRoute/Exposure LevelsStudy Laboratory
L-Tryptophan
73-22-3		03/07/1978Dosed-Feed
0,25000,50000 PPM/35 PER GROUP		Southern Research Institute

Levels of Evidence

Male Rats: Negative
Female Rats: Negative
Male Mice: Negative
Female Mice: Negative