Health risk assessment of heavy metal accumulation in fruits exposed to geothermal waters: a case study and global implications

BACKGROUND: The present study investigated the potential health risks of heavy metals (HMs) in the fruits and leaves of mulberry and sour cherry trees exposed to water from Sivas geothermal basin (Turkey). RESULTS: The target HMs were ranked according to their hazard index as: Cd < Pb < Zn < Cu < Ni < Mn < Cr. The total hazard index for mulberry and sour cherry fruits was calculated as 7.87 and 4.57, respectively, and was determined to be well above the safe threshold value of 1.0. At the same time, the calculated cancer risk values exceeded the established maximum limit (1.0 × 10−4) for Ni (6.4 × 10−3) in mulberry fruit and for Cr (1.15 × 10−3) in sour cherry fruit. Ingestion has been identified as the primary route of exposure. The study results showed that Cr and Ni metals were ranked in the order of mulberry fruit > sour cherry fruit > mulberry leaf > sour cherry leaf, and that for mulberry and sour cherry fruit. CONCLUSION: The findings indicate that edible foods exposed to geothermal waters may have adverse effects on human health. Furthermore, the study highlights the necessity of reducing water discharges from geothermal fields and implementing phytoremediation strategies to ensure food safety in geothermally active agricultural basins.