Bromine
At ambient temperature bromine is a brownish-red liquid. It has a similarly colored vapor with an offensive
and suffocating odor. It is
the only nonmetallic element that is liquid under ordinary conditions,
it evaporates easily at standard temperature and pressures
in a red vapor that has a strong disagreeable odor resembling that of
chlorine. Bromine is less active chemically than
chlorine and fluorine but is more active than
iodine; its compounds are similar to those of
the other halogens. Bromine is soluble in organic solvents and in water.
Applications
Bromine is used in industry to make organobromo compounds. A major
one was dibromoethane an agent for leaded gasoline, before they were
largely phased out due to environmental considerations. Other
organobromines are used as insecticides, in fire extinguishers and to
make pharmaceuticals. Bromine is used in making fumigants, dyes, flameproofing
agents, water purification compounds, sanitizes, medicinals,
agents for photography and in brominates vegetable oil, used as
emulsifier in many citrus-flavoured solft drinks.
Bromine in the environment
Bromine is a naturally occurring element that
can be found in many inorganic substances. Humans however, have
many years ago started the introduction of organic bromines in the
environment. These are all compounds that are not natural
and can cause serious harm to human health and the environment.
In diffuse crustal rock bromine naturally occurs as bromide salts.
Bromine salts have accumulated in sea
water (85 ppm), from which bromine is extracted.
World production of bromine is more than 300.000 tonnes per year; the
three main producing countries are US, Istrael and the UK. In this last
case it is extracted from sea water at a plant on the coast of Anglesey,
Wales.
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Bromine is corrosive to human tissue in a
liquid state and its vapors irritate eyes and throat. Bromine
vapors are very toxic with inhalation.
Humans can absorb organic bromines through the skin, with food and
during breathing. Organic bromines are widely used as sprays to
kill insects and other unwanted pests. But they are not only
poisonous to the animals that they are used against, but also to
larger animals. In many cases they are poisonous to humans, too.
The most important health effects that can be caused by
bromine-containing organic contaminants are malfunctioning of the
nervous system and disturbances in genetic materials.
But organic bromines can also cause damage to organs such as
liver, kidneys, lungs and milt and they can cause stomach and
gastrointestinal malfunctioning. Some forms of organic bromines,
such as ethylene bromine, can even cause cancer.
Inorganic bromines are found in nature, but whereas they occur
naturally humans have added too much through the years. Through
food and drinking water humans absorb high doses of inorganic
bromines. These bromines can damage the nervous system and the
thyroid gland.
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Organic bromines are often applied as
disinfecting and protecting agents, due to their damaging effects
on microorganisms. When they are applied in greenhouses and on
farmland they can easily rinse off to surface water, which has
very negative health effects on daphnia, fishes, lobsters and
algae.
Organic bromines are also damaging to mammals, especially when
they accumulate in the bodies of their preys. The most important
effects on animals are nerve damage and next to that DNA damage,
which can also enhance the chances of development of cancer.
The uptake of organic bromine takes place through food, through
breathing and through the skin.
Organic bromines are not very biodegradable; when they are
decomposed inorganic bromines will consist. These can damage the
nerve system when high doses are absorbed.
It has occurred in the past that organic bromines ended up in the
food of cattle. Thousands of cows and pigs had to be killed in
order to prevent contagion of humans. The cattle suffered from
symptoms such as liver damage, loss of sight and depletion of
growth, decrease of immunity, decreasing milk production and
sterility and malformed children.
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