Human health risk of exposure to potentially toxic metals (PTMS) in indoor settled dusts from selected worship centres (WCS)

Abstract

The study aimed to determine the concentration of potentially toxic metals (PTMs) and the health risk of exposure to indoor dust from worship centres in Abeokuta, Nigeria. Twenty-four (24) dust samples were collected from various corners of selected worship centres. One (1) gram of the sieved dust was digested using aqua regia. PTM analyses were done using an Atomic Absorption Spectrometer (AAS). The result revealed the presence of Iron (Fe)> Zinc (Zn)>Manganese (Mn)> Lead (Pb) > Copper (Cu) >Nickel (Ni) > Cadmium (Cd) (1050; 81.6; 72.5; 3.304; 2.43; 0.516; 0.076 mg/kg) respectively. The PTMs were within the permissible limit for PTMs in dust stated by UK and Dutch Intervention. Pollution indices revealed Zn as the primary pollutant in the dust. A significant association between Zn, Cu, Ni and Cd while that of Mn and Fe suggest a common origin of anthropogenic and lithogenic sources respectively (p<0.01). Health risk assessment revealed inhalation as the major pathway of PTM exposure with the children population being the most susceptible. Hazard index (HI) values were <1, showing a non-significant non-cancer effect on exposure while the cancer risk estimate shows no carcinogenic risk. Conclusively, the selected worship centres have no PTM concentration of health concern at the time of the investigation. However, regular wet cleaning and close monitoring of the worship centres should be considered.