Health risk assessment of heavy metals in water, air, soil and fish

The study and application of health risk assessment techniques are crucial in order to understand the risk of exposure to heavy metals and other harmful pollutants. It entails evaluating the risks of exposure at various concentrations and with reference to certain standard values approved by World Health Organization (WHO) and United States Environmental Protection Agency (USEPA). Investigation of water contamination with heavy metals has become the prime focus of environmental scientists in recent years. Effluent discharges into aquatic system affect living organisms within the receiving environment. The concentrations of these metals were mostly assessed at 50th, 75th and 95th percentile and various exposure evaluated. This review covers studies in water, air, soil and fish samples. Air risks assessment was not given the needed attention and children were more susceptible to the hazard than adult, especially lead toxicity, resulting in health complications. Heavy metals bio accumulates over time, and lethal upon exposure at low concentrations. This review will assist risk managers to minimize the exposure at optimum level as well as for the government to formulate policies in safe guarding the health of population. Key words: Health risk assessment, pollution, heavy metals, water, air, soil.