“Plastics are hazardous to environment”. Explain this state giving
minimum three points.
Answers
Plastics are not intrinsically toxic or harmful. But plastic carry bags are manufactured using organic and inorganic additives like colourants and pigments, plasticizers, antioxidants, stabilizers and metals.
Colourants and pigments are industrial azodyes which are used to give bright colour to plastic carry bags. Some of these are carcinogenic and likely to contaminate food stuffs, if packed in these carry bags. Heavy metals such as Cadmium contained in pigments can also reach out and prove to be a health hazard.
Plasticizers are organic esters of low volatile nature. They can migrate to food stuffs as a result of leaching. Plasticizers are also carcinogenic.
Antioxidants and Stabilizers are inorganic and organic chemicals to protect against thermal decomposition during manufacturing process.
Toxic metals like cadmium and lead when used in manufacturing of plastic bags also leach out and contaminate the food stuffs. Cadmium when absorbed in the low doses can cause vomiting and heart enlargement. Lead exposure in long term may cause degeneration of brain tissues.
Plastic bags if not disposed properly may find their way into the drainage system resulting into choking of drains, creating unhygienic environment and causing water borne diseases. Recycled /coloured plastic bags may contain certain chemicals, which can leach to the ground and contaminate soil and sub-soil water. Units not equipped with environmentally sound techniques for recycling may create environmental problems due to toxic fumes generated during reprocessing. Some of the plastic bags which contain leftover food or which get mixed up with other garbage are eaten by animals resulting in harmful effects. Because of the non-biodegradable and impervious nature of plastics, if disposed in the soil, they could arrest the recharging of ground water aquifers. Further, to improve the properties of plastic products and to inhibit degradation reactions, additives and plasticisers, fillers, flame retardants and pigments are generally used, these may have health impacts.