Eighteen corn samples collected from Thailand were analysed for fumoni
sins and aflatoxins by high performance liquid chromatography. Fumonis
ins B-1 and B-2 were detected in 16 (89%) and 12 (67%) samples at leve
ls ranging from 63 to 18800 ng/g (mean, 1790 ng/g) and from 50 to 1400
ng/g (mean, 251 ng/g), respectively. Fusarium moniliforme and F. prol
iferatum isolated from Thai corn showed the production of fumonisins i
n corn grit cultures. Aflatoxins B-1 and B-2 were found in 15 and 10 s
amples at mean levels of 72 and 15 ng/g, respectively. It was noted th
at as many as 72.2% (13/18) of samples were coincidentally contaminate
d with fumonisins and aflatoxins. Based on these results, the interact
ion of fumonisin-producers and aflatoxin-producers on kernel infection
and contamination of these mycotoxins in corn is discussed. This is t
he first report on the natural co-occurrence of fumonisins and aflatox
ins in Thailand.