Evaluates the carcinogenic risk to humans posed by the ingestion of several naturally occurring substances. Separate monographs are presented for two food items (salted fish and pickled vegetables), two naturally occurring plant substances (caffeic acid and d-limonene), four heterocyclic aromatic amines found in cooked meat and fish (IQ, MeIQ, MeIQx, and PhIP), and selected mycotoxins (aflatoxins, Fusarium toxins, and ochratoxin A). Conclusions concerning carcinogenic risk are based on a critical review of all relevant studies conducted in humans, experimental animals, and in vitro test systems. Each substance is also profiled in terms of its occurrence, chemical properties, and the pattern and scale of human consumption. The monograph on salted fish concentrates on fish as traditionally prepared in southern China, where very high rates of nasopharyngeal carcinoma have been linked to the consumption of salted fish prepared in a manner which involves putrefaction. Additional data from experimental studies support the conclusion that Chinese-style salted fish is carcinogenic to humans. The carcinogenicity to humans of other salted fish could not be classified on the basis of available data. The monograph on pickled vegetables concentrates on pickled foods prepared by the traditional methods used in some parts of China and Japan, where elevated risks for oesophageal and gastric cancer have been observed. The monograph concludes that pickled vegetables, prepared according to these traditional Asian methods, are possibly carcinogenic to humans. Caffeic acid, which is naturally present in a wide range of fruits, vegetables, and seasonings, was judged to be possibly carcinogenic to humans. In view of the absence of human carcinogenicity data, the report was unable to classify the carcinogenicity of d-limonene, a substance widely found in citrus fruits and many other plant species. For the heterocyclic aromatic amines present in cooked meat and fish, IQ was classified as probably carcinogenic to humans; MeIQ, MeIQx, and PhIP were classified as possibly carcinogenic. The most extensive monograph, on aflatoxins, reviews the large body of data on these mycotoxins, including findings from several studies of cancer in humans and extensive experimental studies of carcinogenicity. On the basis of this review, the monograph concludes that naturally occurring mixtures of aflatoxins are carcinogenic to humans and that aflatoxin M1 occurring in milk is possible carcinogenic. For the remaining mycotoxins, toxins derived from Fusarium moniliforme and ochratoxin A, which has been linked to Balkan endemic nephropathy, were classified as possibly carcinogenic to humans. Toxins derived from Fusarium graminearum, F. culmorum, F. crookwellense, and from Fusarium sporotrichioides could not be classified on the basis of available data.

DC.IARC

eng.

WHODOC

WHO monograph

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