Azodicarbonamide, also known as a foaming agent, is widely used in the plastics industry. When heated, it decomposes and releases gasses that cause the plastic to expand and foam. Azodicarbonamide is used in a variety of applications including: toys, shoe soles, yoga mats, and car interiors. It has come under scrutiny in recent years due to its potential health effects. When inhaled, azodicarbonamide can irritate the respiratory system and cause asthma. The International Agency for Research on Cancer has classified it as a “possible human carcinogen”. In light of these concerns, some companies have started to phase out the use of azodicarbonamide.