Toxicity Profile for beta-Carotene (1991)

Abstract

beta-Carotene occurs naturally in the diet. In man, prolonged ingestion of carotene-containing vegetables or beta-carotene supplements can lead to high levels of beta-carotene in the body (hypercarotenaemia) and a yellow colouring of the skin. The colouring fades when dosing is stopped. Whilst there is some indication of subtle influences on the blood, it is not yet clear whether these can be described as toxic effects. Epidemiological studies have provided fairly convincing support for a link between low dietary or blood levels of beta-carotene and a higher lung cancer risk. Protection against other cancer types has been less clearly demonstrated in man. beta-Carotene provoked a recurrence of symptoms when ingested by patients with dermatitis and one individual exhibited a skin reaction following local contact.

No toxic effects were seen when rats, mice, hamsters and dogs were fed repeated high doses of beta-carotene. Two multi-generation feeding studies in rats revealed no adverse effects, but mild depression of pup growth and delayed bone development was reported in rat studies in which beta-carotene was fed to females during pregnancy. No reproductive effects were seen when pregnant rabbits were given oral doses. Lifetime feeding studies gave no evidence of carcinogenicity in rats and mice. beta-Carotene was not mutagenic in the Ames bacterial test and did not induce chromosomal damage when fed to mice. Equivocal results have been reported in tests for DNA damage in bacteria. beta-Carotene produced transient irritation in the eye of rabbits.