One of the components of biodegradable materials used in the production of biodegradable bags:polylactic acid ( PLA ).Nowadays, many methods of dealing with white pollution are landfill or incineration. The main component of ordinary PLA stic bags is polyethylene (PE), PVC(pv), polypropylene (PP), polystyrene resin (P.S.),Combustion produces a carcinogen”Dioxins”this substance is difficult to excrete when inhaled by people. When the content in the body reaches a certain amount, it will cause a series of diseases and harm the human body. The burning of waste PLA stics will produce thick smoke and irritating toxic and harmful gases, which will pollute the atmosphere and seriously pollute the environment.When incinerating polylactic acid ( PLA ), its combustion calorific value is the same as that of incinerating paper, which is half that of incinerating traditional PLA stics (such as polyethylene), and the incineration of polylactic acid will never release toxic gases such as nitrides and sulfides. The human body also contains lactic acid in monomeric form, which indicates the safety of this decomposing product. Compared with ordinary PLA stic bags, biodegradable bags containing polylactic acid are healthy, environmentally friendly and safe. Biodegradable bags under natural or industrial composting conditions180It is decomposed into carbon dioxide and water in the sky, and does not pollute the environment.