preapre a talk to be delivered on the hazards plastic waste as part of environmental awareness programme
Answers
Answer:
The problem created by the use of plastics bags is primarily due to shortcomings in the waste management system. Indiscriminate chemical additives pose environmental problems including choking open drains, ground water contamination, etc.
What are Plastics?
Plastics are polymers i.e. large molecules consisting of repeating units called monomers. In the case of plastic bags, the repeating units are ethylene. When ethylene molecules are polymerized to form polyethylene, they form long chains of carbon atoms in which each carbon is also bonded to two hydrogen atoms.
What are plastic bags made of?
Plastic bags are made from one of the three basic types of polymers -polyethylene- High Density polyethylene (HDPE), Low Density Polyethylene (LDPE), or Linear Low-Density Polyethylene (LLDPE). Grocery bags are generally of HDPE, and bags from the dry cleaner are LDPE. The major difference between these materials is the degree of branching of the polymer chain. HDPE and LLDPE are composed of linear, un-branched chains, while LDPE chains are branched.
Are plastics harmful to health?
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.