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Electric
cars and lead pollutionby Ann Gethin
Electric cars have been thought of as one answer to our dependence on
fossil fuel burning vehicles. Their main appeal is that they produce no air pollution at
the point of use so provide a way of shifting emissions to less polluted areas.
Unfortunately also "out of sight" are the environmental consequences of
manufacturing and recycling the lead- acid batteries electric vehicles require to run on.
A recent report in Science (Lave et al, vol. 268, p 993. May 1995) drew
attention to the problem of lead batteries in electric cars: "Smelting and recycling
the lead for these batteries will result in substantial releases of lead to the
environment". The researchers compared the power, efficiency and environmental
effects of electric cars with petrol powered vehicles. Not only are electric cars
comparatively slower and far more restricted in the distance they can travel but release
more lead into the environment as well.
The study showed that an electric car with batteries made from newly mined lead
releases 60 times more lead than that of a car using leaded petrol. (Their example uses
the relatively high 2.1 g/gallon leaded petrol used in the US in 1972 and in some
Australian states up to the 1990).
Although the lead discharged in lead smelting and reprocessing is
generally less available to humans in the U.S. than that dispersed by leaded petrol cars
driving where people are living (only one percent of U.S. petrol sold is leaded) - there
are still significant hazards. Lead processing facilities release lead into the air and
waterways, and lead in solid waste leaches slowly into the environment.

Electric car by Alexander Claud aged 10. |
Clearly electric cars, despite their "good for the
environment" image create far more of a problem than leaded petrol cars. In addition
"If a large number of electric cars are produced, the demand for lead for batteries
will surge, requiring more lead to be mined." (ibid, p.995)
Manufacture needs to be halted until an alternative safer power source is found. This
rules out current alternatives such as nickel-cadmium and nickel metal hydride batteries
which are also highly toxic and far more expensive. Researchers speculate that
sodium-sulphur and lithium-polymer technologies may eventually be used.
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