Alternaria mycotoxins in food commodities marketed through e-commerce stores in China: Occurrence and risk assessment

The natural occurrence of mycotoxins like Alternaria mycotoxins in food commodities is concerning in terms of health risks for humans. Currently, detailed investigations of Alternaria mycotoxins, such as alternariol (AOH), alternariol methyl ether (AME), tenuazonic acid (TeA), tentoxin (TEN), and altenuene (ALT) in food commodities marketed through e-commerce stores in China remains scarce. In addition, not many studies have focused on the associated dietary risk of these mycotoxins. This study conducted a survey (486 samples) for five Alternaria mycotoxins using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) methods. Among five Alternaria mycotoxins, TeA had the highest occurrence rate (51.0%) and concentration (average concentration of 40.6 mu g/kg) in food commodities, followed by TEN, AOH, AME, and ALT. Millet and tomato products were contaminated with higher levels of TeA than other types of food commodities. The combination of TeA + TEN and AME + TeA + TEN were the predominant two contamination patterns detected in cereal and fruit products. Chronic dietary exposures to Alternaria mycotoxins were performed by the threshold of toxicological concern (TTC) approach. The mean and 95th percentile chronic dietary exposures to AOH and AME indicated different risk levels for consumers in China, with the highest exposure observed in the 2-7 years group, indicating potential dietary health concern. The mean chronic dietary exposures to TeA and ALT did not indicate a risk for the consumers, but the exposure to TeA through cereal product consumption exceeded the TTC value in the 2-12 years group at 95th percentile evaluation. Therefore, strategies should be continuously adopted to decrease or eliminate the occurrence of Alternaria mycotoxins in food commodities in order to reduce the dietary risks for humans.