In the early 20th century, Thomas Midgley Jr. personally demonstrated the safety of leaded gasoline and CFC refrigerants, making them commercially successful.
In 1924, in front of journalists, American inventor Thomas Midgley Jr. Pour a lead additive onto your hands and then inhale the vapors for about a minute. “I can do this every day without any health problems,” he said. But Midgley later required medical treatment. Not only his own health, this action also led to much more dire consequences.
Midgley continued to make his mark with another devastating invention, a solution to the need to replace toxic and flammable gases used for refrigeration and air conditioning. He discovered that CFCs, or chlorofluorocarbons, were an ideal substitute and were harmless to humans, but did not know it would destroy the ozone layer.
Midgley’s two inventions have been praised for decades. However, 100 years after the 1924 press conference, the Earth is still recovering from their negative impacts.
Leaded gasoline mixture
One of the biggest problems facing the auto industry in the early 20th century was engine knocking – small explosions in car engines caused by poor gasoline quality, creating unpleasant sounds and possibly causing damage. The task of solving the problem of engine knocking was assigned to Midgley when he was a chemical engineer at American automobile manufacturer General Motors in 1916.
Under the direction of Charles Kettering, another famous American inventor and head of research at General Motors, Midgley studied thousands of substances, including arsenic, sulfur, and silicon, to find substances that could Can be added to gasoline to reduce knocking sound. Finally, he discovered tetraethyl lead, a lead derivative marketed simply as Ethyl. Leaded gasoline was first sold in Dayton, Ohio, in 1923, then spread throughout the world.
The lead-containing Ethyl mixture was commercially successful. Image: Colin Creitz/The Enthusiast Network
Lead is highly toxic, there is no safe level of exposure and can adversely affect development in children, causing impaired intelligence and behavioral disorders, according to the United Nations Children’s Fund (UNICEF). . An estimated 1 million people each year still die from lead poisoning, according to the World Health Organization (WHO).
Lead’s toxicity became widely known when Midgley added it to gasoline, but that didn’t stop Ethyl from being a commercial success. “There were warnings because lead was considered a poison. But the auto industry’s argument at that time was that there was no evidence that lead released from car exhaust pipes hurt people,” Gerald Markowitz , professor of history at the City University of New York, said.
However, Ethyl production workers quickly suffered negative effects. After the 1924 press conference, Midgley himself was poisoned.
“Midgley wrote in a letter in January 1923 that he had a little bit of lead poisoning and that he did indeed have lead poisoning for the rest of his life. This condition doesn’t really go away when you take in a lot of it.” lead into the body. It’s a serious and long-term problem,” said Bill Kovarik, professor at Radford University.
CFC refrigerant
A few years after the discovery of Ethyl, Midgley, again motivated by Kettering, began developing non-toxic, non-flammable substitutes for refrigerant gases, such as ammonia for use in appliances and air conditioners. air conditioning, leading to many fatal incidents in the 1920s.
Midgley discovered Freon – a methane derivative composed of carbon, chlorine and fluorine atoms – and the first CFC compound. In a public demonstration in 1930, he inhaled the gas and blew out a candle, demonstrating its safety.
After World War II, manufacturers regularly used CFCs in all kinds of products, such as aerosol cans. Image: Joe Sohm/Visions of America/Universal Images Group
Freon, as well as subsequent CFCs, achieved commercial success and led to a sharp increase in air conditioning use in the United States. After World War II, manufacturers began regularly using CFCs in all sorts of products, including pesticides and hairspray.
Decades after CFCs were born, scientists discovered that this group of substances had punched a hole in the ozone layer above Antarctica. If left unchecked, the hole will expand to the point of threatening all life on Earth.
Long-term impact
By 1996, leaded gasoline was phased out in the US, then phased out worldwide. The last country to do so was Algeria, which will still sell leaded gasoline until 2021. A 2022 study estimated that half of the current US population was exposed to dangerous levels of lead as children, but the damage was done. The loss to world health is more difficult to estimate.
In 1987, the Montreal Protocol was signed to gradually phase out CFCs from 1989 to 2010, after which this group of substances was banned. The hole in the ozone layer is improving and will probably heal, but it will take about half a century.