Heavy Metals and Health Risk Assessment of Topsoil in Primary School Playgrounds in Edo State, Nigeria

The accumulation and contamination of the environment by heavy metals is a serious problem around the world due to their toxicity and persistence. Thus, the concentrations of heavy metals in the top soils of selected public primary school playgrounds were determined using standard methods. Results showed that Cadmium (Cd) was below detection limits in all the Stations, while Lead (Pb) was only detected in Station 2 (0.01±0.01mg/kg). Among all the heavy metals analyzed, Iron (Fe) had the highest mean concentration across all the stations, with minimum and maximum values of 16.57±3.39mg/kg (Station 1) and 18.87±1.03mg/kg (Station 3), respectively. The values of heavy metal pollution index (Contamination Factors, Contamination Degree, Pollution Load Index, Geoaccumulation Index) were less than one across the three stations, which implies that all stations were practically uncontaminated. Assessment of health risks of heavy metals to children indicates that heavy metal concentrations in this study pose no health risk to children. Concentrations of all the heavy metals examined were below the critical limits for WHO, FEPA and EU. However, regular monitoring to avoid the accumulation of heavy metals, which can lead to health hazards, is strongly recommended.