Posted by: Didapper PJ21 MAY 2014
Thomas Midgley Jr, born 125 years ago last Sunday, was a US chemist who was feted in his lifetime but now has a darker reputation because of the impact of his work on the environment and on human health.
While working for General Motors in 1921, Midgley discovered that adding tetraethyl lead (TEL) to petrol prevented knocking in car engines. GM heavily promoted the compound as superior to existing antiknock compounds, but over the next few years many workers at factories producing TEL suffered lead poisoning, and 10 died.
At a GM press conference in 1924, Midgley demonstrated TEL’s supposed safety by pouring it over his hands and inhaling its vapour, declaring that he could do this daily. However, it took him nearly a year to recover from the lead poisoning brought on by this stunt.
Then, at the end of the 1920s, GM’s Frigidaire division decided to seek a safe alternative to the compounds then used as refrigerants, since all these substances (eg, chloromethane, ammonia, propane and sulphur dioxide) could be hazardous in the event of a leak. Midgley was a member of the research team that eventually synthesised dichlorofluoromethane (Freon), the first chlorofluorocarbon (CFC). CFCs soon replaced the earlier refrigerants and were later also used as propellants in aerosol products and asthma inhalers.
Of course, we now know about the disastrous effects of both TEL and CFCs. One environmental historian has claimed that Thomas Midgley has had a greater adverse impact on the environment than any single organism in world history.
Midgley met his end in an unusual way, killed by another of his inventions. In 1940 he contracted poliomyelitis and was left disabled. To help his carers raise him from his bed he devised a system of ropes and pulleys. But one day in 1944 he became entangled in the ropes and strangled himself, at the age of 55.