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Zinc exists naturally in air, water and soil.
It is present everywhere in the environment.
All life on earth has evolved in the presence
of zinc, which is used by nature for specific
biological processes. Zinc is essential for plants
too - zinc-deficient soils present in many parts
of the world are a cause of low crop yields.
The human body contains 2-3 grams of zinc. Zinc
is essential for good health. It is responsible
for the proper functioning of more than 300 enzymes
in the human body, and is vital for the immune
system, the expression of genes and the transfer
of nervous signals. The recommended daily intake
of zinc is 12 mg/day for women, 15 mg/day for
men and 7-11 mg/day for children, depending on
age.
Modern life is inconceivable without zinc. Zinc's
principal use is to protect steel from corrosion.
Zinc is also used to purify water and power electric
vehicles, to make brass, automotive equipment
and household appliances, fittings, tools and
toys, in building and construction, in pharmaceuticals
and cosmetics, to produce rubber, in fertilizers
and animal feed, etc.
Zinc protects steel from corroding. Thanks to
zinc, car manufacturers can now guarantee no rust
for up to 12 years. Corrosion is estimated to
cost a nation's economy about 4% of GDP. This
cost is dramatically reduced when steel is protected
with zinc, which lengthens the life of steel by
a factor of at least 5.
By prolonging the life and durability of steel,
zinc helps save vast amounts of energy that would
otherwise be required to frequently replace corroded
steel structures and manufactured goods. If the
steel sheet used in Sweden, for example, were
not protected with zinc, the country would waste
energy corresponding to one nuclear power plant
every year!
Zinc is completely recyclable without any loss
of its physical or chemical properties. 80% of
all the zinc used is recycled sooner or later.
Due to the long life-span of most zinc products,
which in some cases last maintenance-free for
over 100 years, much of the zinc produced in the
past is still in use, constituting a valuable
and sustainable resource for future generations.
By protecting steel from corrosion, zinc makes
possible new uses for steel. For example, a typical
American family home, traditionally built with
timber, can now be built at a competitive cost
from six scrap automobiles, instead of 1 acre
(0.4 hectares) of forest. In world areas where
deforestation is a problem and natural habitats
need to be protected, zinc-coated steel is helping
to provide practical solutions.
Zinc-coated steel is practically maintenance-free,
which means considerable savings over the lifetime
of a steel product. In the case of public infrastructure,
this advantage is significant when translated
into lifetime cost savings, since public funds
that would otherwise need to be spent on maintenance
and replacement are freed up for other purposes
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