Black pepper [pipernigrum]: Evidence of carcinogenicity

Abstract

An extract of black pepper was applied cutaneously to albino Swiss mice of both sexes; each animal received a total of 28 mg over a three‐month period. All pepper‐treated mice surviving after 17 months developed tumors, particularly in the lung, liver, and skin (distant from the area of application). The incidence of malignant tumors and of multiple tumors was significantly greater in the pepper‐treated mice than in the vehicle‐treated controls.