The unscientific disposal of waste is a main source of soil pollution. In order to mitigate heavy metal exposure strategies, the main purpose of the present study was to provide background data to understand the effect of municipal solid waste dumping on topsoil and the health risk assessment of soil heavy metals. Health risk assessment provides information for the reduction of environmental pollution and for reducing its effects. Soil samples were taken at three sampling points (10, 20 and 30 m) away from the dumping waste at depths of 15, 30 and 45cm. Heavy metals, including Cu, Pb, Zn, Ni and Cd, were analysed using standard methods. The level of contamination of heavy metals in a dumpsite soil was assessed by contamination indices, including contamination factor (CF), degree of contamination (CD), pollution load index (PLI) and geo-accumulation index (I-geo). The health risks via the three pathways were detected. The carcinogenic and non-carcinogenic health risks and lifetime cancer risk were evaluated based on inhalation, ingestion, and dermal routes of exposure to metals. CF showed low environmental risk potential as CF values were less than one (CF 30 > 45cm while that of the PLI was still 15 > 30 > 45cm. No major risk was contributed for adults and children in the dumping site as the risk index (HI), which is the summation of hazard quotients of individual metals, posed no harmful effect to both adults and children's health as HI < 1. Overall, LCR for adults was in the range of 1 × 10-7 – 10-8, whereas LCR for children was in the range 1 × 10 – 10-8, which is regarded as negligible for the three pathways via ingestion, inhalation and dermal contact.
Okon et al. (Wed,) studied this question.