Risk assessment of heavy metal pollution in water, sediment, and fish from the Musi River Estuary, Indonesia.

Heavy metal contamination in estuarine ecosystems remains a significant environmental challenge, with severe implications for both aquatic biodiversity and human health. This study provides a detailed investigation into the concentrations and associated health risks of cadmium (Cd), mercury (Hg), arsenic (As), chromium (Cr), and copper (Cu) in water, sediment, and fish from the Musi River Estuary in South Sumatra, Indonesia, an area heavily influenced by industrial and agricultural activities. Using Atomic Absorption Spectrophotometry (AAS), concentrations of Cd, Hg, and As in water exceeded environmental quality standards, raising concerns about the aquatic health of the region. While sediment metal levels were below regulatory thresholds, fish tissues, particularly in the liver, exhibited significant bioaccumulation, providing clear evidence of trophic transfer of contaminants. Health risk assessments, including Estimated Daily Intake (EDI), Target Hazard Quotient (THQ), Hazard Index (HI), and Carcinogenic Risk (TR), indicated that, while general exposure to metals remained within safe limits, species such as Johnius belangerii exhibited elevated THQ and HI values, suggesting potential health risks for consumers. This study introduces valuable insights into metal bioaccumulation dynamics and species-specific responses in tropical estuarine systems, offering crucial information for adaptive environmental management. The findings underscore the need for ongoing monitoring and stricter management policies to address escalating pollution risks due to anthropogenic pressures in the region.