The fumonisin B1 content in corn from North China, a high-risk area of esophageal cancer.

Fusarium moniliforme is the primary fungus contaminating corn throughout the world. Fumonisin B1 (FB1) is the major metabolite of F. moniliforme. It has been shown that FB1 is the promoter and initiator of liver cancer in rat. The corn of Cixian, in Hebei Province, the high-risk area for esophageal cancer in China, is often contaminated by this fungus. A total of 21 corn samples were collected from households in the Cixian County. High levels of FB1 (88.90+/-13.1 microg/g) were found in 10 moldy samples, and low levels (1.40+/-0.50 microg/g) of FB1 were found in 11 apparently healthy corn samples. The positive detection rates of FB1 in moldy and normal samples were 100 and 90.9%, respectively. The frequency of FB1 contamination in the high-risk area is about twice that in the low-risk areas, and the average content of FB1 in samples from high-risk areas was approximately three times that from low-risk areas. Our data indicate that FB1-contaminated corn may be involved in the carcinogenesis of esophageal cancer in high-risk areas of North China.