Assessment of heavy metals in herbal teas: implications for human health risks

Due to the increasing demand for locally sourced herbal teas, alongside rapid industrial development and anthropogenic activities, ecological balance and human health have become more susceptible to adverse environmental impacts. Consequently, comprehensive research is essential to monitor heavy metal concentrations in herbal teas frequently consumed in Türkiye. In this study, 36 medicinal plant samples were obtained from various herbalists in Gaziantep (n=17) and Şanlıurfa (n=19) between May and September. The samples underwent wet digestion using 10 mL of HNO₃ in a CEM Mars 6 microwave system, followed by elemental analysis via SpectroBlue ICP-OES. The concentrations identified in this study were generally within the thresholds specified for plants; however, the Total Target Hazard Quotients (TTHQ) for some herbal tea samples approached or exceeded the threshold of 1, indicating potential non-carcinogenic concerns under conservative exposure assumptions. While As, Cd, Hg, Pb, and Sn levels were below the European Commission (2006) limits for food supplements, the findings suggest that the heavy metal profile of the studied regions is largely within acceptable limits, yet requires continuous monitoring due to specific elemental accumulations. This study underscores the critical importance of continuous monitoring and regular control of heavy metal accumulation in herbal products to ensure public safety.