Determination and risk characterization of polycyclic aromatic hydrocarbons of tea by using the Margin of Exposure (MOE) approach.

Tea is one of the most frequently consumed drinks due to its favourite taste and the health benefit. Tea is produced by several processes and drying is very important step to develop the flavour and destroys the enzymes in tea. However, during drying tea, polycyclic aromatic hydrocarbons some of which are carcinogen and genotoxin are naturally produced. The risk of PAHs by drinking tea was characterized by determining contents of 4 PAHs in tea. 4 PAHs including Benz(a)anthracene (BaA), Chrysene (CHR), Benzo(b)fluoranthene (BbF) and Benzo(a)pyrene (BaP) were investigated by GC-MS in total 468 tea products, which were contaminated up to 4.63 ng g-1. Mate tea was the most highly contaminated by BaA, CHR, BbF and BaP and followed by Solomon's seal and Chrysanthemum. The Margin of Exposures calculated by the concentration of BaA, CHR, BbF and BaP and consumption amount of tea were higher than 10,000, and the risk of PAHs in tea were low concern to public health.