International Agency for Research on Cancer (IARC) - Summaries & Evaluations

(Group 3)

For definition of Groups, see Preamble Evaluation.

VOL.: 71 (1999) (p. 345)

CAS No.: 94-36-0
Chem. Abstr. Name: Dibenzoyl peroxide

5. Summary of Data Reported and Evaluation

5.1 Exposure data

Exposure to benzoyl peroxide may occur in its manufacture and use as an initiator in polymer production, food bleaching and rubber curing. Consumer exposure occurs from acne medications and dental products containing benzoyl peroxide.

5.2 Human carcinogenicity data

Two case–control studies have evaluated exposure to benzoyl peroxide among cases of malignant melanoma. One of these studies (the smallest) (among chemists) suggested a greater frequency of exposure among cases than controls. A third large population-based case–control study, designed specifically to evaluate the possible risk of benzoyl peroxide used as an acne medication among young persons, included largely cases of basal-cell carcinoma of the skin. There was no association with use of benzoyl peroxide in this study.

5.3 Animal carcinogenicity data

Benzoyl peroxide was tested in two studies by skin application in strains of mice susceptible to the development of skin papillomas and in several skin-painting studies in mice and in one study in hamsters in combination with known carcinogens. In one study by skin application in mice, it induced benign and malignant skin tumours and, in the other study, benign skin tumours. Benzoyl peroxide was active as a skin tumour promoter in several strains of mice.

5.4 Other relevant data

Benzoyl peroxide forms radicals that are involved in its covalent binding to macromolecules. Its biological effects are inhibited by antioxidants.

Its genotoxic properties have received little attention. DNA damage has been observed in treated mammalian cells, but it is not mutagenic in bacteria and does not cause chromosomal damage in cultured mammalian cells or dominant lethal effects in mice.

5.5 Evaluation

There is inadequate evidence in humans for the carcinogenicity of benzoyl peroxide.

There is limited evidence in experimental animals for the carcinogenicity of benzoyl peroxide.

Overall evaluation

Benzoyl peroxide is not classifiable as to its carcinogenicity to humans (Group 3).

Previous evaluations: Vol. 36 (1985); Suppl. 7 (1987)


Last updated: 8 April 1999

    See Also:
       Toxicological Abbreviations
       Benzoyl peroxide (ICSC)
       BENZOYL PEROXIDE (JECFA Evaluation)