Assessing spatial distribution, potential ecological and human health risks of soil heavy metals contamination around a Trailer Park in Nigeria

Abstract

This paper examined the ecological and health risks of potentially toxic metals (Cd, Cu, Pb and Zn) in soils around the Gateway Trailer Park, Ogere, Nigeria. Seventy-two (72) composite soil samples at depth of 0–15 cm from six different locations around the Trailer Park and Forest (control) were collected. Metals concentrations were determined using Atomic Absorption Spectroscopy. Contamination factor (CF), degree of contamination (CD), index of geo-accumulation (Igeo) and the potential ecological risk (PER) were also assessed and health risk assessment were calculated using hazard index (HI), total hazard index (THInc) and cancer risk (CR) following standard methods. Mean concentration of heavy metals in soils around the Trailer Park ranged from (0.17–2.35 mg/kg) Cd; (17.90–57.60 mg/kg) Cu; (14.39–23.36 mg/kg) Pb; and (50.41–113.0 mg/kg) Zn. Heavy metal concentrations followed the order of Zn>Cu>Pb>Cd. Mean Cd and Pb were higher than recommended limits for soil by the regulatory agency in Nigeria. Contamination factor and degree of contamination showed moderate to high contamination while geo-accumulation index (Igeo) in respect of Cu, Pb and Zn showed extreme contamination. Soils in the Trailer Park had very high PER while total hazard index (THInc) and carcinogenic risk (CR) indicated that children had highest health risk.