The pollutant cadmium in water may arise from
industrial discharges and mining wastes. Cadmium
is widely used in metal plating. Chemically, cadmium
is very similar to zinc, and these two metals frequently
undergo geochemical processes together. Both metals
are found in water in the +2 oxidation state. The effects
of acute cadmium poisoning in humans are very serious.
Among them are high blood pressure, kidney damage,
destruction of testicular tissue, and destruction of
red blood cells. Cadmium may replace zinc in some
enzymes, thereby altering the stereo-structure of the
enzyme and impairing its catalytic activity.
Cadmium and zinc are common water and sediment
pollutants in harbours surrounded by industrial
facilities. Concentrations of more than 100 ppm dry
weight sediment have been found in harbour
sediments.
Inorganic lead arising from a number of industrial
and mining sources occurs in water in the +2
oxidation state. Lead from leaded gasoline used to
be a major source of atmospheric and terrestrial lead,
much of which eventually enters natural water systems.
Despite greatly increased total use of lead by
industry, evidence from hair samples and other
sources indicates that body burdens of this toxic metal
have decreased during recent decades. This may be
the result of less lead used in plumbing and other
products that commonly come in contact with food
or drink. Acute lead poisoning in humans causes severe
dysfunction in the kidneys, reproductive system,
liver, and the brain and nervous system.
The pollutant cadmium in water may arise fromindustrial discharges and mining wastes. Cadmiumis widely used in metal plating. Chemically, cadmiumis very similar to zinc, and these two metals frequentlyundergo geochemical processes together. Both metalsare found in water in the +2 oxidation state. The effectsof acute cadmium poisoning in humans are very serious.Among them are high blood pressure, kidney damage,destruction of testicular tissue, and destruction ofred blood cells. Cadmium may replace zinc in someenzymes, thereby altering the stereo-structure of theenzyme and impairing its catalytic activity.Cadmium and zinc are common water and sedimentpollutants in harbours surrounded by industrialfacilities. Concentrations of more than 100 ppm dryweight sediment have been found in harboursediments.Inorganic lead arising from a number of industrialand mining sources occurs in water in the +2oxidation state. Lead from leaded gasoline used tobe a major source of atmospheric and terrestrial lead,much of which eventually enters natural water systems.Despite greatly increased total use of lead byindustry, evidence from hair samples and othersources indicates that body burdens of this toxic metalhave decreased during recent decades. This may bethe result of less lead used in plumbing and otherproducts that commonly come in contact with foodor drink. Acute lead poisoning in humans causes severedysfunction in the kidneys, reproductive system,
liver, and the brain and nervous system.
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