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Nomination Summary for Cimetidine (N91221)

Nominated Substances: Cimetidine

Nomination Date: 03/11/1991

Nominator: Private Individual

Rationale: This commonly used gastric acid inhibitor appears to increase SCE frequency in ulcer patients and following in-vitro incubation of human lymphocytes. It also produces chromosomal aberrations in rodent models. Inadequate testing for carcinogenicity.

NTP Principles: not specified

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