Natural co-occurrence of multi-mycotoxins in unprocessed wheat grains from China

This study aimed at assessing the occurrence of twelve mycotoxins, including deoxynivalenol (DON) and its derivatives, 3- and 15-acetyl-deoxynivalenol (3-ADON and 15-ADON), nivalenol (NIV), zearalenone (ZEN), fumonisins (FB1, FB2 and FB3) and aflatoxins (AFB1, AFB2, AFG1 and AFG2) in 338 unprocessed wheat samples harvested in 2018 from China by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). DON was found to be the most predominant and abundant mycotoxins followed by 3-ADON, 15-ADON, NIV, FB1, ZEN, FB3, FB2, AFB1, AFB2, AFG2 and AFG1. Samples from Hubei and Anhui provinces that situated the Yangtze River recorded a higher positive rate for Fusarium mycotoxins. The positive rate and average concentration of fumonisins in wheat samples are relatively low while the co-occurrence of fumonisins as well as DONs and its derivatives 3-ADON and 15-ADON, ZEN and/or NIV was found to be 37.6%. Moreover, compared with wheat samples in 2017, the combined levels of DON and its derivatives, 3-ADON and 15-ADON in wheat samples harvested in the year of 2018 is higher with the incidence of co-occurrence of DON + 3-ADON + 15-ADON significantly raised which may due to the increased precipitation weather conditions. These findings suggest the necessity of monitoring contamination of Fusarium mycotoxins and further raise concerns as to DON + 3-ADON + 15-ADON co-occurrence in wheat in China in order to protect consumers’ health from the toxins exposure risks. •Twelve mycotoxins are detected in 338 wheat samples harvested in 2018 from China.•Deoxynivalenol (DON) is the most abundant toxin detected in wheat samples.•The incidence of co-occurrence of DON, 3-ADON and 15-ADON in 2018 is raised.•The incidence of co-occurrence of fumonisins with other Fusarium toxins is 37.6%.