A Brief Meta-analysis and Health Risk Assessment of Lead and Cadmium in Meat, Liver, and Kidney of Livestock in Iran

Background: Red meat from livestock is an excellent source of high-quality protein, vitamins, and minerals. Objective: This meta-analysis aimed to investigate the levels of two of the most toxic heavy metals; lead (Pb) and cadmium (Cd) in meat and edible offal (liver and kidney) of livestock (sheep, buffalo, and cow) in Iran with assessing their health risk of developing cancer. Methods: A systematic search was conducted covering ISI Web of Science, PubMed, and Google Scholar. Finally, data from 4 articles including 624 samples were analysed. Results: Pooled results show that the mean concentrations of Pb and Cd were 0.18 mg/kg and 0.13 mg/kg respectively which were both higher than their eligible maximum limits by FAO/WHO. The Estimated Daily Intake (EDI) of Pb and Cd in meat, liver, and kidney for adults and children was lower than the Total Daily Intake (TDI) limits. The consumers' non-carcinogenic risk (THQ) for meat consumption was generally safe in terms of Cd and Pb in all cities except for Pb in Hamadan which was greater than one (unsafe) for both adults and children. Carcinogenic Risk (CR) for meat consumption was generally safe or within the acceptable range in terms of Cd and Pb in all cities except for Pb in Hamadan which had a Pb-CR greater than safe/permissible level for children. Conclusion: It can be concluded that the dangerous levels of CR and THQ of meat in terms of Pb in Hamadan warrant concern and further study.