Toxic Metal Detection in Various Types of Tea from Certain Regions of China: Spatial Pollution Characteristics and Potential Health Risk Assessment

Abstract

Tea is one of the most popular beverages in the world, but toxic metals in tea could threaten human health. The toxic metal pollution status of tea in China at a national level remains unclear. Here, we detected the cadmium (Cd) and arsenic (As) concentrations of tea collected from 22 provinces in China. The major points are the following: (1) average concentrations of Cd and As of tea samples in China were 1.163 and 0.485 mg/kg, respectively; the Cd but not As levels exceeded the standards from the Ministry of Agriculture of the People’s Republic of China (NY 659-2003). Cd and As average concentrations were higher in the Southern and Western regions at 5.730, 0.071 and 0.510, 0.580 mg/kg, respectively, compared with the Eastern and Northern regions at 0.203, 0.040 and 0.455, 0.463, respectively. The concentration of Cd was highest in kuding tea at 21.98 mg/kg, whereas the As concentration was highest in jasmine tea at 0.76 mg/kg. (2) The health risk assessment yielded target hazard quotients for Cd and As of 0.1989 and 0.1432, respectively. The total hazard index was 0.3421, and the cancer risk was 8.949 × 10–4. (3) The principal component analysis revealed higher Cd pollution in the Western and Southern areas, which may be related to mining activities. This is the first national-scale investigation of the toxic metals Cd and As in tea across China. Our findings provide a useful reference for ensuring the quality and safety of tea production and suggest the need for constant monitoring of toxic metals in tea to limit the risk of exceeding permitted limits.