Comprehensive Assessment of Mercury Contamination and Health Risks from Artisanal and Small-Scale Gold Mining (ASGM) in Sukabumi, Indonesia

Mercury (Hg) pollution from artisanal and small-scale gold mining (ASGM) is a global environmental and public health concern. In Indonesia, ASGM remains widespread, yet assessments of multimedia contamination and health risks are limited. This study quantified Hg concentration in water, sediment, soil, fish, and cassava to evaluate environmental pollution and potential health risks in Waluran, Sukabumi, Indonesia. Mercury concentration in ASGM was higher than in the reference area, especially in fish (median: 4.76 mg/kg dw), cassava leaves (median: 15.7 mg/kg dw), and tailing sediments (median: 171 mg/kg dw). A remarkably high Hg concentration (9760 mg/kg dw) was detected in soil from amalgam-burning spots. An elevated Hg concentration was observed in the reference area, suggesting widespread contamination and potential for long-range dispersion. Over 85% of ASGM samples were categorized as heavily to extremely contaminated by the geo-accumulation index (Igeo). Bioaccumulation assessment indicated a high bioconcentration factor (BCF) in fish and moderate bioaccumulation factor (BAF) in cassava roots. Hazard Quotients (HQ) were greater than 1 for most exposure pathways in both adults and children, with the greatest risk deriving from cassava leaf consumption. These findings indicate severe Hg contamination within ASGM-affected communities and underscore the urgent need for public health interventions, environmental monitoring, and strengthened regulations to reduce Hg exposure in Indonesia.