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.


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:

L-5-Hydroxytryptophan (4350-09-8)


Study Results

Genetic Toxicology

An overview of Genetic Toxicology Bacterial Mutagenicity study conclusions related to L-5-Hydroxytryptophan (4350-09-8).
Bacterial Mutagenicity
  • Negative

Citation Information

NTP. L-5-Hydroxytryptophan (4350-09-8). Chemical Effects in Biological Systems (CEBS). Research Triangle Park, NC (USA): National Toxicology Program (NTP).


Mortelmans, K., Haworth, S., Lawlor, T., Speck, W., Tainer, B., and Zeiger, E. Salmonella mutagenicity tests. II. Results from the testing of 270 chemicals Environ. Mutagen. Vol. 8 (Suppl 7) (1986) 1-119
Teratologic Evaluation of L-5-Hydroxytryptophan in CD Rats
Final Report - Teratologic Evaluation of L-5-Hydroxytryptophan in CD-1 Mice

Study Data

Genetic Toxicology Studies

Genetic Toxicity Evaluation of L-5-Hydroxytryptophan in Salmonella/E.coli Mutagenicity Test or Ames Test. Study 344778
Summary Data

Other NTP Studies

Prenatal Developmental Toxicity Study (TER82086) of L-5-Hydroxytryptophan (4350-09-8) in Sprague-Dawley Rats Exposed via Gavage
Prenatal Developmental Toxicity Study (TER82087) of L-5-Hydroxytryptophan (4350-09-8) in Swiss CD-1 Mice Exposed via Gavage