The reason why non-stick cookware, all in the bottom of that layer called "Teflon" coating. This substance is a general term for a fluorine-containing resins, including PTFE, FEP and various fluorinated copolymer of propylene, because these compounds have a high temperature, low temperature, self-lubricating, chemical stability, etc., it is widely for non-stick cookware, waterproof breathable material (such as waterproof clothing), leather, automotive parts, and microwave popcorn bags. PFOA is the production of Teflon additives necessary for the process, although in the final product has no trace, but still may be decomposed at high temperatures. Study found that Teflon at high temperatures, and will release a dozen harmful gases, causing some respiratory sensitive animals died. But these gases toxic effects on the human body has not been determined. From a health point of view: non-stick wok is not healthy, as the U.S. Environmental Protection Agency decision, ordered eight companies such as DuPont chemical company gradually reduced until deactivated manufacture Teflon coating the core components required for PFOA. So far lasted for three years, "Teflon dispute" has finally set the official tone. World Health Organization experts suggest that people should choose safe, healthy and beneficial Chinese wok. According to the EPA requirements, in 2010 to cut 95 percent of PFOA use by 2015 to fully disabled.