Since its inception in the 16th century, toxicology has been perceived as The Science of Poison. The term, however, is defined as a multidisciplinary subject dealing with the study of effects stemming from the interaction of physical and chemical agents with living organisms. Metals ions being readily absorbed through food, air, and water interact with biomolecules causing conformational changes and ultimately causing geno- as well as cytotoxicity. In a similar manner regular use and discharge of pesticides causes bioaccumulation in the food chain and thus pose a serious threat to living beings. Environmental toxicology as mentioned in the preceding section is a branch of toxicology that deals with the impact of diverse toxicants on the environment. Environmental contaminants are now widely considered as a critical reason for the concern due to the multiple examples of their harmful effects on human health and the environment.