Aflatoxin Sampling and Testing Proficiency in the Texas Grain Industry

Timothy J. Herrman, Kyung-Min Lee, Benjamin Jones, Cynthia McCormick


Aflatoxin is a group I carcinogen and represents a significant public health and food safety risk throughout the world. Aflatoxin contaminated cereals and oilseeds that contain greater than 20 μg/kg of the toxin (B1, B2, G1, G2) are defined as adulterated by the Texas Commercial Feed Rules and are regulated by the Texas Feed and Fertilizer Control Service.  This study was performed to assess sampling and testing of maize for aflatoxin contamination. During 2010, 87 Texas grain elevators’ sampling procedures were assessed and a second investigation documented aflatoxin analysis procedures at 41 grain elevator establishments.  The average sample size was 1.8 kg (4 pounds) and fewer than 20% of the grain elevators collected samples using an official (prescribed) sampling pattern by the grain inspection, crop insurance or regulatory authorities within the United States. Proficiency samples were analyzed by 39 cooperating grain elevators and 7 firms accurately analyzed samples containing greater than 300 μg/kg aflatoxin. While sampling contributes to variability in measuring aflatoxin in grain, this study highlights that aflatoxin analysis using commercially available test kits is a major contributor to variation in aflatoxin test results among commercial grain handlers.


Aflatoxin, Risk management, Proficiency test, variability, sampling, analysis

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