Arsenic speciation in soil from urban recreational parks and human health risk assessment

It has become increasingly apparent that the pollution of urban recreational parks with arsenic (As) and its species can pose a serious threat to the environment as well as to human health, but risk assessments are limited, especially in developing countries. As concentration, species, and associated human health risks were assessed in soils collected from various urban recreational parks in Pakistan. Human health risks via ingestion, inhalation, and dermal contact were estimated numerically in terms of average daily dose (ADD), hazard quotient (HQ), hazard index (HI) and total carcinogenic risk (TCR) for the exposed children and adults.Total arsenic (TAs) concentrations were within permissible limits in all cities, with Faisalabad having the highest mean and Islamabad having the lowest. Across all sites, arsenobetaine (AsB) and As(III) concentrations were below detection limits (BDLs), while monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA) were detected in only two and three parks, respectively. All the samples indicated that As(V) was the highest among the As species, ranging from 1.55 -15.06 mg/kg. According to the risk assessment study, children were exposed to high levels of As. The highest ADD values, as 2.69E-05, 7.51E-10, and 7.53E-08 for children and 3.79E-06, 2.39E-10 and 1.21E-08 were reported in Faisalabad. The mean HQ, HI, and cancer risk values were < 1, indicating that the As-related health risks are unlikely for the exposed population. The results of this study are crucial to developing suitable management strategies in urban recreational parks to minimize soil contamination and human exposure.