Fusarium moniliforme and fumonisins in corn in relation to human Esophageal cancer in Transkei

Abstract

Homegrown corn samples were collected from areas with high and low rates of human esophageal cancer in the southern African territory of Transkei for six seasons over the period of 1976–1989. The most consistent difference in the mycoflora of the corn kernels was the significantly higher incidence of Fusarium moniliforme in corn from high-vs. low-rate areas. In the 1989 samples, this significant (P<0.01) difference in high- and low-rate cancer areas was 41.2 and 8.9%, respectively, in good (visibly nonmoldy) corn and 61.7 and 21.4%, respectively, in moldy (visibly Fusarium-infected) corn. The samples collected in 1985 and 1989 were analyzed for the presence of two secondary metabolites of F. moniliforme, the carcinogen fumonisin B1 (FB1) and its structural analogue fumonisin B2 (FB2). Significantly higher levels of both FB1 and FB2 were present in the samples from the high-rate esophageal cancer areas. Certain samples from the high-rate areas contained some of the highest levels of FB1 (up to 117,520 ng/g) and FB2 (up to 22,960 ng/g) yet recorded from naturally infected corn.