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


VOL.: 31 (1983) (p. 213)

CAS No.: 117-39-5
Chem. Abstr. Name: 4H-1-Benzopyran-4-one, 2-(3,4-dihydroxyphenyl)-3,5,7-trihydroxy-

5. Summary of Data Reported and Evaluation

5.1 Experimental data

Quercetin has been tested for carcinogenicity in mice, rats and hamsters in several experiments by administration in the diet and in mice by skin application and urinary bladder implantation. Increased incidences of ileal and urinary bladder carcinomas were observed in only one experiment in rats fed quercetin, whereas several other experiments, using the same or higher doses, do not provide evidence of a carcinogenic effect.

The 3-rhamnoglucoside of quercetin (rutin) was tested in rats and hamsters by administration in the diet. No evidence of carcinogenicity was found.

Quercetin is mutagenic in bacteria and insects and caused gene conversion in yeast. Equivocal results were obtained with respect to mutations in mammalian cells in vitro. It induced chromosomal anomalies in cultured cells, but equivocal results were obtained in the micronucleus test in vivo. Quercetin induced morphological transformation of hamster embryo cells in vitro. There is sufficient evidence that quercetin is active in short-term tests.

In one experiment with rats, no teratogenic effect was seen.

5.2 Human data

The natural occurrence of quercetin in fruit and other edible plants results in wide human exposure to this compound.

No data were available to evaluate the teratogenicity or chromosomal effects of this compound in humans.

No case report or epidemiological study of the carcinogenicity of quercetin was available to the Working Group.

5.3 Evaluation

Results from one experiment in rats provide limited evidence for the carcinogenicity of quercetin in experimental animals. In the absence of epidemiological data, no evaluation of the carcinogenicity of quercetin to humans could be made.

For definition of the italicized terms, see Preamble Evaluation.

Subsequent evaluations: Suppl. 7 (1987) (p. 71: Group 3); see also Vol. 40 (1986) (Bracken fern); Vol. 73 (1999)


Last updated: 30 September 1999

    See Also:
       Toxicological Abbreviations
       Quercetin  (IARC Summary & Evaluation, Volume 73, 1999)