Size-exclusion chromatography selective cleanup of aflatoxins in oilseeds followed by HPLC determination to assess the potential health risk

Abstract

Aflatoxins (AFs) are one of the most harmful carcinogenic natural toxins that affect food. Crops containing reasonably high oil content may be affected by Aspergillus species and consequently by AF contamination. In this study, a proposed testing method for AF detection in oilseed was developed, validated, and used for a market survey to assess the probabilistic risk exposure caused by consuming contaminated oilseeds including corn, sunflower seed, and soybean. The test method was optimized for selective extraction and then validated for fitness of purpose; the limits of quantification (LOQs) were 0.2, 0.4, 0.2, and 0.2 μg kg−1 for aflatoxin G1 (AFG1), aflatoxin B1 (AFB1), aflatoxin G2 (AFG2), and aflatoxin B2 (AFB2), respectively. The method was linear from the LOQs up to 20 μg kg−1, and its budget of measurement uncertainties were estimated at 25, 24, 26, and 30 for AFG1, AFB1, AFG2, and AFB2, respectively. The contamination levels were from <LOQ to 2.65 μg kg−1 and from <LOQ to 26.9 μg kg−1 for corn and sunflower oilseed samples, respectively, whereas the soybean samples were AF-free. According to the consumption rate of corn and sunflower seeds, the estimated margins of exposure to AFB1 were 721 and > 10,000 body weight (BW) day−1, respectively. The main finding of the present study highlights the possibility of some risk of AF exposure from corn consumption, which may represent a health concern.