National Toxicology Program

DEPARTMENT OF HEALTH AND HUMAN SERVICES
Public Health Service

National Toxicology Program (NTP); Availability of Technical Report on Toxicology and Carcinogenesis Studies of Benzethonium Chloride

The HHS' National Toxicology Program announces the availability of the NTP Technical Report on the toxicology and carcinogenesis studies of benzethonium chloride, which is used primarily in cosmetics for its antimicrobial and cationic surfactant properties.

Toxicology and carcinogenicity studies were conducted by dermal administration of benzethonium chloride to groups of 60 F344/N rats and 60 B6C3F1 mice of each sex at doses of 0, 0.15, 0.5, or 1.5 mg/kg body weight. Benzethonium chloride was adminstered to rats in ethanol 5 days per week and doses were adjusted weekly according to the average body weights of the groups. As many as nine rats per group were evaluated after 15 months. Mice received doses administered in ethanol and dose volumes were adjusted weekly according to average body weights of the groups. As many as ten mice per group were evaluated after 15 months of chemical administration.

Under the conditions of these 2­year dermal studies, there was no evidence of carcinogenic activity* of benzethonium chloride in male or female F344/N rats or in male or female B6C3F1 mice.

Exposure of rats and mice to benzethonium chloride by dermal application in ethanol for 2 years resulted in epithelial hyperplasia in male and female rats and mice and sebaceous gland hyperplasia and ulcers in female rats at the site of application.

Questions or comments about the Technical Report should be directed to Central Data Management at P.O. Box 12233, Research Triangle Park, NC 27709 or telephone (919) 541-3419.

Copies of Toxicology and Carcinogenesis Studies of Benzethonium Chloride (CAS No. 121-54-0) (TR-438) are availabe without charge from Central Data Management, NIEHS, MD E1-02, P.O. Box 12233, Research Triangle Park, NC 27709; telephone (919) 541-3419 or send e-mail to CDM@niehs.nih.gov.

Dated: August 21, 1996

 
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Kenneth Olden, Ph.D.
Director
National Toxicology Program

[Billing Code 4140-01]

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*The NTP uses five categories of evidence of carcinogenic activity observed in each animal study: two categories for positive results ("clear evidence" and "some evidence"), one category for uncertain findings ("equivocal evidence"), one category for no observable effect ("no evidence"), and one category for studies that cannot be evaluated because of major flaws ("inadequate study").