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https://theconversation.com/leaded-petrol-probably-affected-the-mental-health-of-millions-of-americans-new-study-245418>
"In its various forms, lead has been used in many everyday products for
millennia. The Romans even added it to wine as a sweetener. Its most widespread
use, however, was its addition to petrol. And it is this use that has been
associated with increased mental health disorders, according to a new study
published in the
Journal of Child Psychology and Psychiatry.
Americans, especially those born between 1966 and 1986 (largely so-called
generation X), have probably suffered from an additional 151 million mental
health disorders that would not have occurred without the use of leaded petrol.
The study finds increases in anxiety and depression, attention deficit
hyperactivity disorder (ADHD), and neuroticism, as well as decreases in
conscientiousness.
Although the toxicity of lead for humans has been known for almost as long as
it has been used, the full extent of its effects and the exposure levels at
which they manifest is still being uncovered.
Tetraethyl lead started to be added to petrol in 1921 when three engineers at
General Motors discovered that it greatly improved engine performance and
reduced “knocking” – uneven burning of the fuel that can damage engine parts.
Concerns about the safety of leaded petrol arose immediately when one of the
engineers who made the discovery, as well as several workers producing the
additive, fell sick, and some died of mysterious illnesses. Still, the US
surgeon general dismissed these concerns, citing a lack of evidence of the
effects at the low exposure levels linked with driving.
The discussion on the effects of lead exposure at the time was dominated by
industry-sponsored studies, as recounted in a 2009 book,
Lead Wars:
The Politics of Science and the Fate of America’s Children. Simultaneously,
leaded paint was also marketed as the best paint for its washability and
brightness.
In the 1970s, the invention of the catalytic converter, which does not work
with leaded petrol, and an accumulating body of evidence on the negative
consequences of lead exposure for human health, saw the beginning of the phase
out of leaded petrol. (Regulation was also introduced in the US to ban leaded
paint for residential purposes in 1978).
Even though its use had already decreased, the UK banned leaded petrol in 1999,
and Algeria was the last country to officially ban it in 2021.
The resulting gradual reduction of lead in the environment has offered a useful
setting for researchers to widen our understanding of the widespread
consequences of lead exposure among children and adults. For example, a study
in Sweden compared children born in areas closer to motorways, who would have
been more exposed to lead emissions from cars, to those born farther away.
By studying how the differences in these two groups changed over time as leaded
petrol was phased out, they found that lead exposure lowers educational
outcomes, increases the risk of criminal activity, and can lower lifetime
earnings.
These effects on crime, educational attainment and engagement in “risky
behaviour” have been found in the US, too."
Cheers,
*** Xanni ***
--
mailto:xanni@xanadu.net Andrew Pam
http://xanadu.com.au/ Chief Scientist, Xanadu
https://glasswings.com.au/ Partner, Glass Wings
https://sericyb.com.au/ Manager, Serious Cybernetics
