Lead touched many areas of Roman life. It made up pipes and dishes, cosmetics and coins, and paints. Eventually, as a host of mysterious maladies became more common, some Romans began to suspect a connection between the metal and these illnesses.
Julius Caesar , for example, managed to father only one child, even though he enjoyed women as much as he enjoyed wine. His successor, Caesar Augustus , was reported to be completely sterile. Some scholars suggest that lead could have been the culprit for the condition of both men and a contributing factor to the fall of the Roman Empire. A form of lead intoxication known as saturnine gout takes its name from ancient Rome.
Saturn was a demonic god, a gloomy and sluggish figure who ate his own children. Better working practices could make tetraethyl lead safe to produce. But was it really sensible to add it to petrol, when the fumes would be belched out on to city streets? About a century ago, when General Motors had first proposed adding lead to petrol - in order to improve performance - scientists were alarmed.
They urged the government to investigate the public health implications. Midgley breezily assured the surgeon general that "the average street will probably be so free from lead that it will be impossible to detect it or its absorption", although he conceded that "no actual experimental data has been taken".
General Motors funded a government bureau to conduct some research, adding a clause saying it had to approve the findings. The bureau's report was published amid the media frenzy over Oelgert's poisoned workmates. It gave tetraethyl lead a clean bill of health and was met with some scepticism.
Under pressure, the government organised a conference in Washington DC in May The debate there exemplified the two extremes of approach to any new idea that looks risky, but useful. He called leaded petrol a "gift of God", arguing that "continued development of motor fuels is essential in our civilization".
In the other corner: Dr Alice Hamilton, the country's foremost authority on lead. She argued leaded petrol was a chance not worth taking. Hamilton knew that lead had been poisoning people for thousands of years. In , workers who made lead white - a pigment for paint - were described as suffering ailments including "dizziness in the head, with continuous great pain in the brows, blindness, stupidity". The Romans used lead in water pipes.
Lead miners often ended up mad or dead - and some correctly intuited that low-level, long-term exposure was also unwise. Many societies still grapple with the general question on which Howard and Hamilton disagreed: how much pollution is a price worth paying for progress? There's some evidence that as countries get richer, they tend initially to get dirtier and later clean up. Economists call this the "environmental Kuznets curve", and it makes intuitive sense.
If you're poor, you prioritise material gains. As your income grows, you may choose to spend some of it on a nicer, safer environment. But was lead-free petrol really such an expensive luxury? True, the lead additive solved a problem: it enabled engines to use higher compression ratios, which made cars more powerful.
Refrigerators in the s were often appallingly risky because they used dangerous gases that sometimes leaked. One leak from a refrigerator at a hospital in Cleveland, Ohio, in killed more than a hundred people.
Midley set out to create a gas that was stable, nonflammable, noncorrosive and safe to breathe. Unlike compounds such as ammonia, butane yes, really and sulphur dioxide, freon could be breathed by people and wasn't flammable. Lead-based paint was banned in However, house renovation disturbs old paint and this may expose new proprietors to lead poisoning. The U. Clean Air Act banned the sale of leaded gasoline effective January 1, beginning a phasedown that ended in a complete phase-out by But there was still more damage to be done.
In , Thomas Midgley found within three days that dichlorodifluoromethane could be used as a refrigerant gas in residential refrigerators and air conditioners. This was quickly commercially manufactured as Freon by Kinetic Chemicals, where he was the director. To demonstrate the CFC gas was safe he inhaled a large amount of the gas, and blew out a candle flame to show it was non-toxic and non-flammable, therefore, safe.
The freon gas is considered to be one of the major contributors to ozone depletion and was banned for production. The Chlorofluorocarbons CFCs released by aerosols and damaged fridges caused serious and irreparable damage to the ozone layer , the region of the upper atmosphere that protects life on the planet from UV radiation and other forms of radiation that can injure or kill most living things. To the present day, we are still suffering the consequences of Thomas Midgley's deadly inventions.
The purple and blue colors are where there is the least ozone, and the yellows and reds are where there is more ozone.
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