Thomas Midgley Jr. was an American mechanical and chemical engineer. He played a major role in developing leaded gasoline and some of the first chlorofluorocarbons (CFCs), better known in the United States by the brand name Freon; both products were later banned from common use due to their harmful impact on human health and the environment. He was granted more than 100 patents over the course of his career.
Midgley c. 1930s–1940s
Sign on an antique gasoline pump advertising the TEL anti-knock compound Ethyl, a gasoline additive
Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) are fully or partly halogenated hydrocarbons that contain carbon (C), hydrogen (H), chlorine (Cl), and fluorine (F), produced as volatile derivatives of methane, ethane, and propane.
CFCs negatively affecting stratospheric ozone production
NASA projection of stratospheric ozone, in Dobson units, if chlorofluorocarbons had not been banned. Animated version.