Contamination of 15+1 European Union polycyclic aromatic hydrocarbons in various types of tea and their infusions purchased on Hangzhou city market in China

摘要

The purpose of this research was to determine the occurrence of 15 + 1 European priority polycyclic aromatic hydrocarbons (EUPAHs) in various types of tea purchased on Hangzhou city market in China in order to control their safety. The results indicated that the incidence rate of EUPAHs compounds was 97.4%. The total EUPAHs levels ranged from 1.2 μg/kg to 155.6 μg/kg, with a median of 27.1 μg/kg and a mean of 42.3 μg/kg. Cyclopental[cd]pyrene was not only the most frequently detected EUPAH but also detected at the highest concentrations with a mean of 12.2 μg/ kg. The 4-membered and 5-membered ring EUPAHs were detected in nearly all of the tea types and accounted for 83.4% to 100.0% of the total EUPAHs mass distribution. The transfer percentages of EUPAHs from the various tea leaves to tea infusions and effect of infusion time were investigated as well. A transfer rate between 5.9% and 24.2% was found for the EUPAHs and these levels were within the maximum safe consumption limits for drinking water according to European Union regulations (EU Council Directive 98/83/EC).