Assessment of potentially toxic metal(loid)s contamination in soil near the industrial landfill and impact on human health: an evaluation of risk

The generation of solid waste is increasing with each passing day due to rapid urbanization and industrialization and has become a matter of concern for the international community. Leachate leakages from landfills pollute the soil and can potentially harm the human health. In this paper, inductively coupled plasma-optical emission spectrometric studies were employed to assess and analyze the composition of metals (Ba, Cd, Pb, Hg, Cu, Cr and Mn) and metalloid (As) in soil samples. Results of Cr, Mn, Cu, As, Ba, Cd, Pb and Hg from CRM (certified reference material, SRM 2709a) of San Joaquin soil were evaluated and reported in terms of percent recoveries which were in the range of 97.6-102.9% and show outstanding extraction efficiency. Other than copper, where the permitted limit set by the EU is specified as 50-140 mg/kg in soil, the average amount of all the metals in soil was found within the permissible limits provided by WHO, the European Community (EU) and US EPA. Soil contaminated with Hg (PERI = 100) and Cd (PERI = 145.50) posed an ecological risk significantly. Pollution load index (PLI) value is greater than 1, while degree of contamination (C-deg) value is less than 32 which indicated that the soil is polluted and considerably contaminated with metals and metalloid, respectively. In terms of the average daily dosage (ADD) of soil, children received the highest doses of all metals (ADD(ing) = 1.315 x 10(-7 )- 2.470 x 10(-3) and ADD(derm) = 9.939 x 10(-7 )- 5.292 x 10(-11)), whereas ADD(ing) (1.409 x 10(-8 )- 2.646 x 10(-4)) was found greater in adults. For all metals except for Ba, the hazard quotient (HQ) trend in both children and adults was observed to be HQ(ing) > HQ(derm) > HQ(inh) of soil. Children who are at the lower edge of cancer risk had a lifetime cancer risk (LCR) of 2.039 x 10(-4) for Cr from various paths of soil exposure.

Automated summary

The generation of solid waste is increasing due to rapid urbanization and industrialization, and the leachate leakages from landfills pose a threat to human health. This study analyzed the composition of metals and metalloid in soil samples using inductively coupled plasma-optical emission spectrometric studies. The results showed that the levels of metals in the soil were within the permissible limits set by international standards. However, soil contamination with mercury and cadmium posed an ecological risk. Children were found to have the highest exposure to metals through soil, and the cancer risk for chromium was observed to be at the lower edge.