Environmental health risk assessment is a stepwise process to identify a health hazard in the environment and assess the risk associated with it. Hazard refers to a potential harm, while risk refers to the health effect that results when that harm is realised. Hence the first step in environmental health risk assessment is to identify an environmental hazard. Stern (2008) has defined Environmental health risk assessment (EHRA) as a predictive risk profiling of human health risks. According to him, in EHRA exercises, we identify a potential harmful agent and identify what health effects or diseases it can cause and then use various means to predict the health effects that can result from either an actual exposure profile or we model the exposure and predict the level of harm or health effect that will result from it.