Petrol additives: bad decisions again and again


By Peter Montague

The corporate decision in 1923 to add toxic lead to gasoline changed the chemistry of Earth, particularly the northern hemisphere. According to the US National Research Council (NRC), in 1983 industrial emissions of lead into the atmosphere exceeded natural lead emissions by a factor of 700.

In 1983, humans put 330,000 tonnes of lead into the atmosphere, 75% of it from car exhausts. About 90% of lead emissions occur in the northern hemisphere.

In addition, humans in 1983 put another 1 million tonnes of lead directly onto the land in the form of commercial waste, mine tailings, municipal waste, sewage sludge, fly ash from burning coal and so forth.

As a result, says the NRC, "The pandemic scale of lead contamination ... has increased lead concentrations throughout the Northern Hemisphere by a factor of at least 10".

Naturally this translates into contamination of all parts of the ecosystem. According to the NRC:

  • Lead concentrations in terrestrial organisms of all kinds are 100 times as high as natural concentrations. In sum, everything has been poisoned.

  • Humans have pulled about 300 million tonnes of lead out of the earth, and "Most of the ... lead ever produced remains in the environment, largely in soil and dust ... despite reductions in the use of lead for gasoline, overall production continues to grow and federal agencies have not addressed the impact of future increases of lead in the environment."

All of the lead mined out of the deep earth eventually becomes environmental contamination; it is very long-lived, resulting in the progressive, cumulative poisoning of the environment with a potent neurotoxin. All creatures — especially humans, who eat at the top of the food chain — have been severely contaminated and are no doubt suffering subtle and not so subtle impairments.

Lead "consumption" in the US diminished only 8% between 1970 and 1990 even though major uses of lead were banned by the US government. The lead industry is very creative in finding new uses for lead, and, because it is organised in the form of corporations, the industry is incapable of feeling remorse for the irreversible damage it is doing to life on Earth.

Corporations cannot voluntarily curb their misbehaviour because they have only one duty: to return a profit to investors, no matter what the costs may be to others. So long as poisoning is legal, corporations will poison.

The amount of lead in a person's blood that is officially considered "safe" today is 10 micrograms of lead in each decilitre of blood, or 10 mg/dL.

According to the most recent estimates, in the period 1991-1994, somewhere between 613,000 and 1.4 million US children younger than six years (mostly African Americans and Hispanics living in large cities) had average blood lead levels of 10 mg/dL or more; a third of these children had blood lead levels of 15 mg/dL or more.

The NRC said in 1993, "There is growing evidence that even very small exposures to lead can produce subtle effects in humans. Therefore, there is the possibility that future [safety] guidelines may drop below 10 mg/dL as the mechanisms of lead toxicity become better understood."

The NRC offers evidence that lead at 5 mg/dL can cause attention deficit, reduced birth weight and hearing loss in children.

The NRC summarises a series of recent studies, then says, "Those studies support the general conclusion that there is growing evidence that there is no effective threshold for some of the adverse effects of lead". If this is true, it means the only safe level of lead is zero.

One way to get today's "safe" level of lead (10 mg/dL) into perspective is to compare it to the natural background levels found in the blood of prehistoric people — who lived in an environment that had not been poisoned by the members of the Lead Industries Association.

According to careful measurements of human bones, pre-Columbian inhabitants of North America had average blood lead levels of 0.016 mg/dL — some 625 times lower than the level now established as "safe" for children. On the face of it, it seems unlikely that levels of a potent nerve poison 625 times as high as natural background can be "safe".

The decision to add toxic lead to gasoline could have gone differently back in 1925.

The basic problem was engine "knock". In a high-compression engine, the fuel tended to explode instead of burning evenly. As a result, the engine made a "knocking" sound, power fell dramatically and the engine could eventually be damaged.

As Charles F. Kettering, president of the Ethyl Corporation, said in 1925, the British (and later the Japanese) solved this problem by burning a higher grade of gasoline in a smaller, more efficient engine.

The US chose another path: larger, less efficient engines fuelled by lower-quality gasoline, which was improved with an anti-knock additive. As a result of this basic strategy, the US consumed 80% of all the world's leaded gasoline until 1970.

Even the decision to select lead as the anti-knock additive could have gone another way. In 1925, Dr Harriet Hardy of Harvard told a lead-in-gasoline conference, "I would like to make a plea to the chemists to find something else, and I am utterly unwilling to believe that the only substance which can be used to take the knock out of a gasoline engine is tetraethyl lead ..."

Yandell Henderson of Yale told the same conference that such alternatives existed: "I have asked some of the chemists, my colleagues in Yale University, and I have found that lead is not by any means the only substance which, on theoretical grounds, or even on the basis of experiments, can be used as an antiknock medium".

If the corporations had been required by law to study all available alternatives (a process described in the federal National Environmental Policy Act of 1969) and then to adopt the least damaging alternative, the poisoning of the northern hemisphere could have been averted.

Instead, the corporations poisoned every creature on half the planet without serious, open discussion of how they might have behaved differently.

The Ethyl Corporation went on to compound its errors. When the corporation was forced in 1972 to start phasing out leaded gasoline, Ethyl began selling one of leaded gasoline's components — ethylene dibromide, or EDB — as a pesticide.

In 1983, the US Environmental Protection Agency took EDB off the market because it readily caused cancer in several species of animals, damaged sperm cells and sperm production in humans and harmed reproduction in other ways. At the time EDB was banned, the US was putting 9 million kilograms of it into soils each year, and it was showing up in cake mixes and cereal.

In 1995 the Ethyl Corporation did it again. The corporation began marketing a new anti-knock gasoline additive, methylcyclopentadienyl manganese tricarbonyl, or MMT, a compound of the toxic metal manganese.

According to a group of scientists who have studied the dangers of manganese, MMT gives us reason for "major concerns".

"Inhalation is an abnormal route of intake for manganese and may be associated with increased risk of toxicity, particularly to the central nervous system and the lungs. Certain susceptible subpopulations, such as the young, the old, and the malnourished, may be at greatly increased risk of adverse effects from exposure to manganese in the environment."

Ethyl Corporation insists that manganese is safe. However, to this day Ethyl Corporation also insists that leaded gasoline is safe.
[From Rachel's Environment & Health Weekly. Like Green Left Weekly, Rachel's is a non-profit publication which distributes information without charge on the internet and depends on the generosity of readers to survive. If you are able to help keep this valuable resource in existence, send your contribution to Environmental Research Foundation, PO Box 5036, Annapolis, Maryland 21403-7036, USA. In the United States, donations to ERF are tax deductible.]

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