KY Vijay Kumar | ENS Chennai, PLASTIC is an environmental hazard chiefly because it is nonbiodegradable. It cannot be decomposed by micro-organisms or by any biological process. It is a synthetic polymer that can be moulded into complex shapes. Elasticity makes it extremely popular as a packaging material. In its packaging form, plastic has a molecular weight ranging from several thousands to about 1,50,000. This excessive weight makes plastic resistant to change and consequently leads to its persistence in the soil. According to Ligy Philip, Associate Professor, Environmental and Water Resources Department, IIT Madras, heavy metals present in plastic get accumulated over many years in landfills. When the metals come into contact with water, they leack out and seep into groundwater. This contaminates and makes water unsafe for human consumption.