Health risk assessment of metal exposure from Jengka Riverine system in Pahang, Malaysia

Abstract

The presence of metals in aquatic and soil ecosystems poses significant environmental and public health concerns, particularly in areas with increasing anthropogenic activities. This study evaluates the concentration of selected heavy metals, namely copper (Cu), chromium (Cr), lead (Pb), and zinc (Zn) in the water and soil of the Jengka Riverine system in Jengka, Pahang, Malaysia as this region is known for extensive agricultural activities. Samples were collected from multiple points along the river, and metal concentrations were analysed using inductively coupled plasma optical emission spectrometry (ICP-OES). Risk assessment models, including the hazard quotient (HQ) and lifetime cancer risk (LCR), were employed to evaluate both non-carcinogenic and carcinogenic risks associated with dermal contact, inhalation, and ingestion. For river water, the average heavy metal concentrations (±standard deviation) were in descending order of Zn (0.033±0.023 mg/L) > Cu (0.013±0.01 mg/L) > Pb (0.007±0.005 mg/L). Cr was not detected in water samples. The average heavy metal concentrations (±standard deviation) in soil showed descending order of Zn (5.33±1.15 mg/kg) > Cu (5.13±2.31 mg/kg) > Cr (3.33±0.305 mg/kg) > Pb (2.02±0.001 mg/kg). The findings indicate slight elevated levels of certain metals indicating potential links to agricultural discharge and road surface runoff. Most HQ and LCR levels in the water and soil samples remained within permissible limits. However, some metal exposure specifically via dermal contact suggests potential long-term risk for local communities relying on the river for food and recreation, especially among children. The study highlights the need for regular monitoring and implementation of mitigation strategies to reduce health risks and preserve the ecology of the Jengka River.