The concentration of the potentially toxic element (PTEs) in black tea (Camellia sinensis) consumed in Iran: a systematic review, meta-analysis, and probabilistic risk assessment study

The contamination of tea as one most widely consumed beverage in Iran with the potentially toxic elements (PTEs) leads to adverse health effects. In the current study, a meta-analysis and probabilistic risk assessment regarding PTEs concentration in tea samples from Iran were performed using international databases (PubMed and Scopus) and national databases (SID, Irandoc, and Magiran) from 2005 to 1 June 2022. Data were analysed using the random-effects model based on Iranian and imported tea subgroups, and a probabilistic health risk assessment was conducted using the Monte Carlo simulation (MCS). The highest THQ in adults and children due to consumption of Iranian tea was related to As (0.0635) and As (0.2964), respectively, and the highest THQ in adults and children due to consumption of imported tea was related to Cu (0.0266) and Cu (0.1242), respectively. TTHQ in adults and children’s consumers due to PTEs ingestion via consumption of Iranian tea was 0.21 and 1.01, respectively, and TTHQ due to PTEs ingestion via consumption of imported tea was 0.22 and 0.94, respectively. Therefore, non-carcinogenic risk in children due to consumption of Iranian tea was higher than 1 value. The mean CR for content of inorganic As in adults and children via consumption of Iranian tea was 2.89E-5 and 1.35E-4, respectively, and the mean CR for inorganic As in adults and children via consumption of imported tea was 9.44E-6 and 4.42E-5 respectively. Hence adults and children, due to both Iranian and imported tea consumption, are at considerable carcinogenic risk. It is recommended to carry out continuous monitoring plans at country customs and reduce sources of tea contamination to PTEs in agricultural fields.