Sponges are poisonous. Sponge is made of polyurethane (PU) and belongs to chemical products. It is mainly made of chemical additives such as "TDI, benzil diamine and cyanide" (prohibited during the Olympic Games), "auxiliary" and "foaming agent". Among them, polyols are irritating volatile gases, which are mainly extracted from petroleum. TDI is a highly toxic chemical, and its production process is extremely environmentally friendly. In addition, toxic, irritating and allergenic chemicals will be released during use, and the structure is very airtight, which is easy to breed bacteria.

Sponges are made of wood fibers or foamed plastic polymers. Sponge is a porous material with good water absorption, which can be widely used to make sofas, mattresses, boss chairs and sports equipment, such as sponge gymnastics mats, sponge fitness mats, sponge wrestling mats, sponge car cushions and other products. In addition to lignocellulosic fibers, there are three kinds of synthetic sponges made of other materials, namely low-density polyether, polyvinyl alcohol and polyester.

Sponge is a kind of foamed polymer, which has the characteristics of fine structure, smooth surface, soft and elastic feel, good cushioning, earthquake resistance, heat insulation, moisture resistance, chemical corrosion resistance, non-toxic, tasteless, water absorption, etc., and can effectively prevent products from being impacted during transportation without polluting chemistry and denaturation plasticity.