About lead contamination
At the moment, it is believed that lead in any quantities that can be found in people’s blood has a negative effect on their health. Children unironically become dumb from the smallest amounts of lead – this is the most dangerous of pollutants from this point of view.
The most dangerous use of lead from the point of view of its entry into the human body was anti-knock metal-organic additives such as tetraethyl lead Pb(C2H5)4. They have been used, for example, in the UK since the 1930s. They increased the octane number of gasoline and increased the efficiency of gasoline engines.
When leaded gasoline is burned, lead is released into the atmosphere in the form of tiny particles of various inorganic lead salts. And the lead content in the blood of city residents correlates with its amount in city dust. The origin of atmospheric lead from leaded gasoline was shown by studying the ratio of various isotopes of lead in this same dust. Leaded gasoline differs from all other possible sources of lead by a specific isotope ratio that differs from natural radiogenic ones. Lead is the end product of the decay of a significant part of natural radioactive elements, this leads to a connection between the isotopic composition of natural lead and the content of various elements in the earth's crust.
Inductively coupled plasma mass spectrometry and various variations on the topic are used to determine small amounts of lead and its isotopes separately. The idea of the method is to ionize a sample to produce atomic ions. A stream of ions is placed in a magnetic field, where, under the influence of the Lorentz force, their trajectories are separated depending on the ratio of mass to charge. Such methods allow the determination of trillionths in tiny samples, and the accuracy of the determination allows the determination of different isotopes of different elements separately.
For roughly these reasons, the use of leaded gasoline in cars was banned at the end of the 20th century. The ban led to a change in the origin of lead in the atmosphere along with a decrease in its content: from car exhaust to industrial sources and the rise of road dust into the atmosphere.
To understand the scale of the tryndets: at the peak of leaded gasoline consumption in the early 80s, about 7 thousand tons of lead escaped into the UK atmosphere per year. In London, there were 500-600 nanograms of lead per cubic meter of air in the atmosphere. By the early 2010s, concentrations had dropped to about 10 nanograms per cubic meter and remain stable to this day.
With the ban on leaded lead, the ratio of its isotopes in urban dust began to shift towards the natural one. However, at the moment, the isotopic composition of lead in London has settled on an intermediate value between that characteristic of lead from leaded petrol and from near-natural sources. This can be considered a sign of retention of old lead from gasoline in city dust.
Thus, even after the ban on leaded gasoline for cars, lead continues to hang in the city air. It is not clear what to do with this, well, if only to bury all the old city soil (like what was done around Chernobyl).
Tetraethyl lead was discovered by the German chemist Karl Jacob Levich, one of the discoverers of bromine, back in 1853. Its ability to increase the octane number of gasoline was discovered by Thomas Midgley Jr. in 1921. He was a professional engineer and self-taught chemical engineer at General Motors, then owned by DuPont. He is also known as the discoverer of CFCs, “a walking environmental disaster” and “the most emitting organism in the history of life on Earth.”
General Motors was just developing and putting into operation gasoline engines with a high degree of compression of the air-fuel mixture. The problem was the loud knocking and clanging noise emitted by the engine, as well as its low service life. Chemists were tasked with finding some kind of fuel additive that would get rid of these negative factors. As it later turned out, detonation of the air-fuel mixture occurred during its compression.
The discovery was made, in general, by accident – Midgley in front of him went through some incredible number of all kinds of trash options, including inhumanly smelly selenium and organotellurium. Organic tellurium even reached the stage of testing on a car, nicknamed by testers “Goat” for its speed of climbing uphill and for the unearthly aromas of the exhaust, reminiscent of, ugh, the exhaust of a goat. And as a result of the tests, Midgley himself had to spend the night in the basement for seven months – his wife did not let him into the house.
In addition to tetraethyl lead and other heavy metal compounds, Midgley personally discovered the anti-knock properties of iodine and aniline, and in the same years the use of iron pentacarbonyl, benzene and ordinary ethanol as such additives reached the stage of industrial production.
Moreover, ethanol was considered such a promising internal combustion fuel in the early 1920s that even the management of GM and DuPont initially viewed their product based on gasoline and lead compounds primarily as a transitional product before launching large-scale production of ethanol fuel. They refused, in fact, due to the impossibility of patenting either the production or use of ethanol and the impossibility of obtaining exclusive rights and excess profits, as a consequence.
The developers were well aware of the toxicity of lead and its compounds. Midgley collected a bag of correspondence warnings about the toxicity of a particular compound from both American and European scientists. In particular, the German scientist Erich Kraus from the University of Potsdam directly warned that it was tetraethyl lead that killed one of the members of his dissertation council. Why, in 1923 Midgley himself spent a long time undergoing treatment for tetraethyl lead poisoning!
Corporate bosses were also aware – the very name of the joint legal entity of GM and Standard Oil, which produced the additive, Ethyl Gasoline Corporation, was chosen purposefully in order to get rid of the negative image of lead in the product and confuse it with ethanol (hence “leaded gasoline”).
It must be said that not all ancestors were idiots obsessed with money, and the issue of the toxicity of lead in the atmosphere was raised, and how, even outside the scientific community a century ago, in the 20s of the 20th century.
In 1924, the Bayway Refinery in New Jersey, literally across the strait from New York City, then owned by Standard Oil, began producing tetraethyl lead. Workers quickly nicknamed him “loony gas.” Those working in the workshop of his production quickly went crazy – people lost their memory, coordination of movements was impaired, and unexpected attacks of rage appeared. By October 1924, in just two months, it had reached the point of loss of consciousness, convulsions and delirium. By this time, out of 49 workshop workers, 32 were in the hospital. Five of them died painfully in straitjackets, screaming loudly while trying to hide from ghosts or fight some kind of winged insects and suffering from uncontrollable muscle spasms. The owner did not give any official comments. One production manager said that “the workers were simply overworked.” He also turned out to be poisoned.
An investigation has begun. SUDDENLY it turned out that neither the personally poisoned developer of tetraethyl lead Midgley, nor the corporate bosses even bothered to study the toxicity of their compound. Officials were sent letters along the lines of “safety issues were taken seriously, but no experimental data were obtained.” Moreover, it was a well-known toxin: in an interview with the then head of the US Army’s chemical warfare service, Brigadier General Fries, he said that tetraethyl lead was seriously planned to be used as a combat gas. The technological process implemented at the factory was extremely unsafe. The process was not continuous, but required regular manual replacement of reagents. Semi-molten lead was removed from the reactor, naturally, with shovels and poured into a grate on the floor. The purity of the product was checked by eye by inserting gloved fingers into it. Damn, moonshine is usually brewed with great respect for safety precautions! Production was temporarily halted as an investigation began.
New York medical examiner, one of the best toxicologists in the United States at this time, Alexander Gettler, wasted three weeks of incessant work examining the bodies of the dead. He had to develop a significant part of the research methodology from scratch. A significant amount of lead was found in the bodies of the victims. Most of it was in the lungs. This indicated the extreme vulnerability of humans to inhalation of lead compounds. In the future, the ineffectiveness of standard gas masks against poisoning was also shown. To make things even more fun, a rapid rate of absorption of tetraethyl lead through unprotected, intact skin was discovered.
After the report of the New York forensic examination, a lot of newspaper articles were published about the toxicity of the new additive. Leaded gasoline was banned in New York, New Jersey, Philadelphia, Pittsburgh… And then the federal authorities intervened. US President Calvin Coolidge, a Republican, a conservative, a fan of the “small state” theory and not the healthiest person in his head, stood on the side of business interests against the damned statists and took the investigation to the level of the federal government.
The feds convened a conference on the safety of tetraethyl lead. Neither doctors, nor toxicologists, nor representatives of cities where leaded gasoline had already been banned took part in it – only chemical technologists from industry on the payroll of big business. The conference lasted only a few hours. They refused to consider alternatives to tetraethyl lead on principle and decided to create a research group on the safety of tetraethyl lead. While this is the case, for PR purposes its production was temporarily suspended.
The research group, the brains of which was the young Dr. Robert Kehoe, already on the payroll of the tetraethyl lead manufacturers, suffered from the same shortcomings. People did find traces of lead in the dust of garages and in the blood of all the drivers examined. In calculations of the level of lead emissions during the combustion of leaded gasoline, the law of conservation of matter was successfully lost – 80% of the lead contained in gasoline disappeared in an unknown direction.
The conclusion turned out to be predictable: “tetraethyl lead poses a small risk to human health, there is no basis for its ban.” It was also stated that there are no alternatives to it as an anti-knock additive. This was an outright lie. As I wrote last time, Midgley himself found many alternatives. How much he found is unknown; GM cleaned up its archives and lab logs. Butanol and benzene, not to mention ethanol, were already presented on the market as anti-knock agents. The launch of thermal cracking units began, increasing the octane number of gasoline without additives. Work was already underway on catalytic cracking.
It must be said that a reservation was left in the conclusion. With the increasing use of automobiles, emissions were expected to increase, “leaded gasoline may pose a hazard to the public after prolonged use or for reasons currently unforeseen.” It was suggested that the study be repeated in the future. The problem, in fact, was openly transferred to the next generation.
All bans on the production, use and sale of leaded gasoline have been lifted by the federal government. The very attempt to ban leaded gasoline was erased from public memory so thoroughly that during the discussion about the ban on tetraethyl lead in the 70s, neither lawyers, nor judges, nor newspapers even remembered the events of the 1920s.
In total, in the 1920s, at least 20 people died and more than 300 people were hospitalized at three plants where they tried to produce tetraethyl lead in the United States. The victims were closed from production due to stupidity. Almost all their relatives were informed of their death. The key production center of this stuff, the town of Deepwater in New Jersey, was absent from the maps in the 20s – chemical weapons were produced there. There was virtually no municipal government, and the police belonged to the owners of industries. All this simplified the process of people disappearing. The archives, as I already said, have been cleaned out. And New York forensic experts have begun determining background levels of lead in city dust for future generations.
After the attempt to ban leaded gasoline described above, almost all research on the topic of lead toxicity in the West was funded by tetraethyl lead producers. Dr. Robert Kehoe from the University of Cincinnati, on the payroll of leaded gasoline manufacturers, has virtually monopolized research on the topic. Official research was carried out through one place and with experiments on people – everything we like. Every year, in factories around the world, someone was buried or locked in an asylum. The US government has banned any criticism of the safety of leaded gasoline by market participants under the pretext of unfair competition. Any attempts to conduct independent research into the safety of lead ended in a lawsuit. For example, Randolph Byers discovered signs of lead poisoning in 20 children in 1943. He was silenced precisely by the threat of legal action.
The issue of lead in the air was again raised by a person completely left in relation to medicine. His name was Claire Patterson, he was a geophysicist and mass spectrometry specialist, one of the participants in the Manhattan Project. As part of his dissertation in the early post-war years, he tried to determine the age of the Solar System through meteorite samples. To do this, it was necessary to determine the ratio of lead isotopes in its samples. However, accurately determining the lead content and isotopic composition of the samples proved unexpectedly difficult.
At some point, Patterson realized that everything around him, the walls of the laboratory, instruments, dust, even he, even the sky, even Allah, were polluted with lead. He created a “clean room” from scratch and protocols for working with samples in such a “clean room”. To finance all this fun, he fed the grantors with lies, telling them about the supposed possibility of using his work in obtaining fuel from uranium. Only after all these measures it was possible to obtain sane results.
In the course of his purely geophysical research, Patterson showed that the background level of pre-industrial lead levels accepted in the scientific community and literature is an artifact of widespread lead pollution. To do this, he studied sediments at the bottom for the money of the same oil refining industry and the ancient ice of the Greenland glaciers, where the American army was just trying to build missile silos. Patterson eventually analyzed a 4,500-year-old Peruvian mummy and demonstrated that the body of a contemporary American contained lead levels about 600 times higher than pre-industrial norms.
By publishing these data, he quite deliberately got to the bottom of industrial research into the safety of lead. This made it possible to criticize the fundamental assumptions of big business theories about the existence of a safe level of lead with which humanity has lived throughout its history. Then Patterson, as an expert, spoke at a meeting of a subcommittee of the US Senate and achieved public criticism and ridicule from business representatives (the same Dr. Kehoe) right in the Senate. For this, Patterson was cut off from funding and almost fired from his job – his university, Caltech, depended on investments from the oil industry.
The effects of lead on children were rediscovered by Herbert Needleman in 1974. He showed that lead levels in teeth are a more reliable marker of poisoning than levels in the blood. He also demonstrated a decline in the cognitive abilities of children poisoned by lead. Big business tried several times to refute Needleman's work through the courts and regulatory authorities. In 1982, they attacked through the EPA (Environmental Protection Agency), in 1991 through the NIH (National Institute of Health), accusing the psychiatrist of violations of scientific ethics without evidence. Even in 2005, after the ban and withdrawal of leaded gasoline from circulation, the hogs tried to cough up the issue through the courts.
In fact, the ban on leaded gasoline turned out to have little to do with its toxicity and negative public attitudes. In 1962, GM suddenly sold half of its incredibly profitable tetraethyl lead business to a small paper manufacturer. It’s almost as if X5 Retail Group would now sell Pyaterochka to a family store on the corner.
In 1969, American authorities brought to light an illegal agreement between all major vehicle manufacturers. His goal was, no less than, joint sabotage of the fight against air pollution. A lawsuit to hold big businesses liable for conspiracy failed. However, it was thanks to this scandal that already in 1970 the United States adopted the Clean Air Act – a law that required a reduction in emissions of unburned fuel, nitrogen oxides and carbon monoxide by 90%. This requirement turned out to be fundamentally impossible to fulfill with leaded gasoline – it shook the platinum in catalytic converters. For several more decades, the chemical industry fought for the right to produce and trade organic lead, and the oil industry fought for the right to use the device to modernize its refineries. But all efforts were unsuccessful, despite the support of the Reagan administration and then Vice President George H. W. Bush.
And any work with organometallic compounds of heavy metals should now theoretically be carried out in disposable chemical protective suits with insulating gas masks.
Author: Ivan Prikhno
