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Boron is a non metallic element and the only non-metal of the group
13 of the periodic table the elements. Boron is electron-deficient,
possessing a vacant p-orbital. It has several forms, the most common of
which is amorphous boron, a dark powder, unreactive to oxygen, water,
acids and alkalis. It reacts with metals to form borides.
At standard temperatures boron is a poor electrical conductor but is a
good conductor at high temperatures.
Applications
The most economically important compound of boron is sodium
tetraborate decahydrate Na2B4O7 · 10H2O,
or borax, used for insulating fiberglass
and sodium perborate bleach. Boric acid is an important compound used in
textile products.
Compounds of boron are used in organic synthesis, in the manufacture
of a particular type of glasses, and as wood preservatives. Boron
filaments are used for advanced aerospace structures, due to their
high-strength and light weight.
An early use of borax was to make perborate, the beaching agent once
widely used in household detergents. Boron compound also came into the
average home in the guise of food preservatives, expecialy for margarine
and fish.
Boron in the environment
Boron is not present in nature in elemental form. It is found
combined in borax, boric acid, kernite, ulexite, colemanite and
borates. Vulcanic spring waters sometime contains boric acids.
Borates are mined in US, Tibet, Chile and Turkey, with world production
being about 2 million tonnes per year.
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Humans can be exposed to boron through fruit and vegetables, water, air and consumer products.
we have a regular daily intake of about 2 mg and about 18 mg in
out body in total.
When humans consume large amounts of boron-containing food, the
boron concentrations in their bodies may rise to levels that can
cause health problems. Boron can infect the stomach, liver,
kidneys and brains and can eventually lead to death. When exposure
to small amounts of boron takes place irritation of the nose,
throat or eyes may occur. It takes 5 g of borc acid to make a
person ill and 20 grams or more to put its life in danger.
Eating fish or meat will not increase the boron concentrations in
our bodies, as boron does not accumulate within the tissues of
animals.
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Boron is an element that occurs in the
environment mainly through natural processes.
Boron occurs naturally in the environment due
to the release into air, soil and water through weathering. It may
also occur in groundwater in very small amounts. Humans add boron
by manufacturing glass, combusting coal, melting copper and
through the addition of agricultural fertilizers. The
concentrations of boron that are added by humans are smaller that
the naturally added concentrations through natural weathering.
Boron exposure through air and drinking water is not very likely
to occur, but the risk of exposure to borate dust in the workplace
does exist. Boron exposure may also occur from consumer products
such as cosmetics and laundry products.
Plants absorb boron from the ground and through plant-consuming
animals it can end up in food chains. Boron has been found in
animal tissue, but it is not likely to accumulate.
When animals absorb large amounts of boron over a relatively long
period of time through food or drinking water the male
reproductive organs will be affected. When animals are exposed to
boron during pregnancy their offspring may suffer from birth
defects or delayed development. Furthermore, animals are likely to
suffer from nose irritation when they breathe in boron.
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Now visit our
boron in water page
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periodic elements
Recommended daily intake of
boron
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