Abstract:Objective To investigate the contamination levels of aflatoxin B1 (AFB1) in fermented tea, including dark tea, black tea and oolong tea, and evaluate their health risk. Methods The sampling was determined by the simple random sampling method. A total of 260 tea samples(dark tea, black tea and oolong tea)were collected from supermarkets, wholesale markets, tea shop and online store in 9 prefecture-level cities of Guangdong Province. AFB1 concentrations were examined according to GB 5009.22-2016. By using the method of margin of exposure (MOE) and mathematical modeling, the AFB1 dietary exposure in tea was assessed. Results The detection rate of AFB1 in 260 fermented tea samples was 1.15% (3/260), and the detected content range was from 0.26 to 0.56 μg/kg. The three AFB1 positive samples of were Pu'er tea samples. There was no significant difference in the detection rate between three kinds of fermented tea (Fisher exact probability method, P>0.05). The average dietary exposure of AFB1 from tea of the total survey population and the tea consumption population were 0.000 352, and 0.000 981 ng/kg BW, respectively. The dietary exposure was 0.005 73,0.016 0 ng/kg BW for the total survey population and the tea consumption population when using the maximum value of AFB1 in this study. On the basis of European Food Safety Authority (EFSA) criterion, the MOE values were both greater than 10 000, indicating that the health risk associated with AFB1 in tea in Guangdong was relatively low. The evaluated liver cancer risk was 0.000 010 9-0.000 674 caners per one hundred thousand persons. Conclusion The detection rate and the content of AFB1 in fermented tea in Guangdong Province were both low. And the health risk associated with AFB 1 in tea was relatively low, either.
