Contamination Characteristics And Human Health Risk Assessment Of Potentially Toxic Elements In Dust From Seven Different Land Use Types.

Abstract

The contamination characteristics, risks, and sources of the potentially toxic elements in dust from seven different land use types were investigated. One hundred and seven (107) dust samples were collected from seven different land use areas and analyzed for lead, arsenic, zinc, copper, iron, manganese, chromium, vanadium, titanium, nickel, and cadmium using a field portable X-Ray fluorescence analyzer. The mean concentration (mg kg-1) ranges of toxic elements in the dust at different land uses were: Pb (3.5 – 42.1), As (3.0 – 4.6), Zn (43.2 – 272.9), Cu (12.1 –54.6), Fe (12792.1 – 28202.3), Mn (101.9 – 321.4), Cr (44.4 – 127.4), V (53.8 – 123.7), Ti (1918.8 – 3746.9), Ni (16.0 – 18.9), and Cd (5.2 – 5.9). Except for cadmium, the potentially harmful element levels in the dust were generally found to be below the background, World Health Organization (WHO), and Dutch target (VROM) guideline limits across all land use zones. According to the results of the geo-accumulation indicator, the dust in Sekyere South was unpolluted to moderately polluted with lead, arsenic, zinc, copper, manganese, iron, chromium, and titanium, moderately polluted with vanadium, and severely polluted with cadmium. The enrichment factor calculation revealed that zinc was moderately enriched, vanadium was significantly enriched, and cadmium was greatly enriched, while the others showed deficient to little enrichment. According to the modified degree of contamination findings, the site has a moderate degree of contamination with cadmium accounting for 57% of thecontamination. The contamination of the site is in the following order: auto mechanic shop > residential > school > lorry park > market > road > playground. Only cadmium posed a very high potential ecological risk in the dust, according to the potential ecological risk rating. The principal component analysis yielded three distinct components of elements. Component one (Ti, V, Cr, and Fe) could be the outcome of natural sources. Component two (Mn, Cu, Zn, As, and Pb) could have come from both human (traffic emissions) and natural sources, whilst component three (Cd and Ni) could have come from waste incineration, agrochemical application, and paints. Children were exposed to higher levels of risk than adults. The study found that all of the potentially harmful elements evaluated were at tolerable levels and are not likely to pose any health risk. The study found a significant cadmium pollution load in the areas, hence proper pollution management methods must be implemented. The findings will assist local governments in developing legislation to protect the environment and human health.