Determination of polycyclic aromatic hydrocarbons concentration in eight brands of black tea which are used more in Iran

Abstract

Aims : The objective of this study was investigation of the polycyclic aromatic hydrocarbons (PAHs) concentration in eight brands of black tea which is used more in Iran. Materials and Methods : In the present study, PAHs content of eight brands of black tea were extracted and analyzed with gas chromatography-mass spectrometry (GC-MS) equipped with Selected Ion Monitoring (SIM) technique. Results: The average of total PAHs compounds in analyzed teas was in the range of 139 to 2082 μg kg ?−1 . PAHs with 5 to 6 rings were not found in the teas samples. Four rings PAHs compounds composed 46% of the total PAHs compounds and were the most dominant compounds. The same compounds were also dominant in tea bags. Conclusion: In the tea liquor, after brewing times of 10 and 120 minutes, the maximum and minimum releasing percentage of PAHs was observed, respectively. The result of this study confirmed the presence of PAHs in the tea leaves and tea liquor. Assuming that every person use 10 g of tea leaves every day and 10 minutes take for brewing time, the daily uptake of 16 PAHs will be 1.2 μg.

Keywords

• Black tea
• gas-chromatography
• poly aromatic hydrocarbons