Thomas Midgley Jr. invented two things that were used all over the world. Firstly, he invented leaded gasoline. This helped car engines operate more efficiently, but at the cost of spewing poisonous gas everywhere. The second invention is Chlorofluorocarbons or "CFCs." These substances, which were sold under the brand name Freon, had widespread applications in refrigerators and aerosols. But it eventually discovered that these CFCs were eating away at the ozone layer in Earth’s atmosphere. Ozone depletion allows more UV radiation to reach the Earth's surface, which can lead to skin cancer, cataracts, and weakened immune systems.

The fact that a single individual invented both of these things which were slowly killing humanity before they were phased out, led Environmental historian J. R. McNeill to say that Midgley "had more adverse impact on the atmosphere than any other single organism in Earth's history."

Before Thomas Midgley died in 1944, he didn’t see himself as destructive. Because the scientific community showered him with praise and prizes and accolades during his lifetime. And he didn’t even have a reason to think he was doing anything bad because the government regulators who were tasked with protecting the American public gave his inventions a pass.
This story represents a complete failure of tech entrepreneurs to consider the adverse impacts that their inventions might have, a failure of the scientific community to check one of their own, and a failure of supposed protectors of the public interest to do their jobs. And all of these failures basically meant that the generation after Midgley was forced to clean up his mess.

REFERENCES

McGrayne, Sharon Bertsch. “Prometheans in the Lab: Chemistry and the Making of the Modern World.” Sharon Bertsch McGrayne, 2001.

Markowitz, Gerald, and David Rosner. “Deceit and denial: The deadly politics of industrial pollution.” Vol. 6. Univ of California Press, 2013.

Cagin, Seth, and Philip Dray. "Between earth and sky: how CFCs changed our world and endangered the ozone layer." 1993.

Tylecote, Ronald F. "Roman lead working in Britain." The British Journal for the History of Science 2, no. 1 (1964): 25-43.

Kovarik, William. "Ethyl-leaded gasoline: how a classic occupational disease became an international public health disaster." International journal of occupational and environmental health 11, no. 4 (2005): 384-397.

Kovarik, Bill. "Charles F. Kettering and the 1921 Discovery of Tetraethyl Lead In the Context of Technological Alternatives", presented to the Society of Automotive Engineers Fuels &

Lubricants Conference, Baltimore, Maryland., 1994
Kitman, Jamie Lincoln. "The secret history of lead." NATION-NEW YORK- 270, no. 11 (2000): 11-11.
https://www.thenation.com/article/archive/secret-history-lead/