Health Risk Assessment of A Heavy Metal Contaminated Site in Taiwan

Potential risk effect from elevated levels of soil heavy metals on human health in the Niger delta

An analysis of the soil quality in the Niger Delta Area (NDA) was carried out to determine the severity of soil contamination. The United States Environmental Protection Agency (US EPA) risk assessment model was used in determining the potential health risk due to lifetime exposure (by means of ingestion, dermal contact and inhalation) of the population to heavy metal contents in the soil. Substantial levels of contamination were found indicating elevated levels of heavy metals above background concentrations from controlled samples in the areas. Median topsoil metal concentrations (0-15cm) in the NDA measured in mg/kg were: Zn 58.3±37.0, Cd 1.3±1.0, Cr(VI) 13.2±5.5, Cu 28.3±31.5, Pb 895.1±423.9, Ni 42.7±20.3, Mn 201.8±77.5 and Fe 1303.5±2028.6. Pb, Ni, Zn, Cd, Cr(VI), Fe and Mn exceeded some guideline and standard values; while the comprehensive levels of total metals contamination exceeded the environmental action level for soils, which could potentially affect human health. The collective total risk (carcinogenic and non-carcinogenic) for minors and adults were established from the model using the slope factors and reference dose of the compounds respectively. The study has shown that soil contamination in the industrial and residential regions are similarly significant; while the risk assessment proved that based on the pollutants concentration in the soil, metals with the highest cancer risk values (Pb=2.62E-02 and Cr(VI)=1.52E-02) have the potential of affecting the health status of the residents, especially for children in the region. The chronic daily intake of the metals are of major concern as their cumulative effect could result to several health complications of children and adults in the region.

Potential health risk assessment for soil heavy metal contamination in the central zone of Belgrade (Serbia)

An investigation of the soil quality in the centre of Belgrade was per- formed to define how seriously the soil is polluted. On the basis of the heavy metal content (Zn, Cd, Pb, Co, Ni, Cu, Cr and Mn), the potential health risk assessment calculated for a lifetime of exposure (ingestion and inhalation), based on the USEPA model, was determined as the cumulative carcinogenic and non-carcinogenic risk for children and adults. The study proved that soil contamination in Belgrade is not insignificant; risk assessment indicated that the carcinogenic risk is completely insignificant but the cumulative non-carcinogenic risk tends to became significant, mainly for children, since it approaches unacceptable values. There is no particularly dangerous single heavy metal, but their cumulative effect, expressed as Child Soil Ingestion Hazardous Index, is for concern.