EVA full name is ethylene vinyl acetate copolymer, belongs to a kind of polymer, the material itself is non-toxic and environmentally friendly, but with its production of floor mats, slippers added to the foaming agent, resulting in formamide toxic. Ethylene-vinyl acetate copolymer is a general-purpose polymer, which itself is non-toxic and environmentally friendly, and its chemical properties can be used as plastics, cosmetics, industrial materials and other products. The use of ethylene vinyl acetate copolymer to make floor mats and slippers requires the use of a foaming agent when foaming, and the combination of substances contained in the ethylene vinyl acetate copolymer and those in the foaming agent, which produces formamide, a low-toxicity class of compounds, is toxic.