Occurrence of mycotoxins in cereals and animal feedstuffs in Natal, South Africa

During the period 1982-1983, just under 800 samples of agricultural commodities, comprising cereals, compound feeds, hay, and silage, were examined for molds and mycotoxins. Aflatoxin B1 showed the highest incidence rate; it occurred in over 27% of all samples analyzed, the highest levels being found in peanut meal at 1500 ppb. Other mycotoxins detected were patulin and a number of trichothecene toxins at incidence rates in all commodities of 5.6 and 3.1%, respectively. The commodities at highest risk were oil seeds, excluding soya bean; the latter was found to be fairly free from contamination with mycotoxins. The most prevalent fungi were Aspergillus flavus and parasiticus, which were found in over 22% of all samples, whereas Penicillium spp. showed the lowest incidence of genera, specifically identified in 8.3% of all samples examined. This latter finding explains in part the low incidence of Penicillium mycotoxins.