Management of Aflatoxin Contaminated Maize in Tamaulipas, Mexico

A rural warehousing facility in the state of Tamaulipas in Mexico stored aflatoxin contaminated maize from 1989 to 1995; its control required national efforts. The aflatoxin contaminated maize was analyzed chemically by immunoaffinity columns, fluorometry, and thin layer chromatography in grain, weeds, and soil of the warehouse “Las Yescas”. Morphological and tributyrine biochemistry tests were done to identify species of Aspergillus in grain, weeds, and soil, and mainly A. flavus was found. The average levels of total aflatoxin found were 66 μg/kg from 42 samples of sieved maize, 295 μg/kg from 49 samples of not sieved maize, 25 μg/kg from seven weed samples, and 112 μg/kg from nine soil samples. Sieving reduced the aflatoxin by 75%. Soil always presented AFB2, and sometimes AFB1, due to the high contamination. Keywords: Aflatoxins; fluorometry; immunoaffinity; contamination; Aspergillus flavus; TLC; carcinogenic; environmental toxicology