Chemistry: Water Pollution
Phosphates in Water Pollution
Phosphates may be created by substituting some or all of the
hydrogen of a phosphoric acid by metals. Depending on the number of
hydrogen atoms that are replaced, the resulting compound is described as
a primary, secondary or tertiary phosphate. Primary and secondary
phosphates contain hydrogen and are acid salts. Secondary and tertiary
phosphates, with the exception of those of sodium, potassium and
ammonium are insoluble in water. Tertiary sodium phosphate is valuable
as a detergent and water softener. The primary phosphates tend to be
more soluble.
Phosphates, which are an important component to metabolism in
both plants and animals, help in the first step in oxidation of glucose
in the body. Primary calcium phosphate is an ingredient of plant
fertilizer.
Phosphates have caused increasing attention recently. The focus
is on the environmentally harmful effects in household detergents.
Wastewater, from laundering agents, contains phosphates, which are said
to be a water pollutant.
Most laundry detergents contain approximately 35% to 75% sodium
triphosphate (Na5P3O10), which serves two purposes. Providing an
alkaline solution (pH 9.0 to 10.5) is necessary for effective cleansing
and also to tie up calcium and magnesium ions found in natural waters
and prevent them from interfering with the cleansing role of the
detergent.
Eutrophication is the progressive over-fertilization of water,
in which festering masses of algae's blooms, choking rivers and lakes.
Phosphorus compounds act as a fertilizer for all plant life, whether
free-floating algae or more substantial rooted weeds, and are implicated
in eutrophication. Many countries control phosphate levels, whereas
Switzerland has banned the use of phosphates.
The marine environment is both fragile and more resistant than
the terrestrial ecosystem. It is fragile for the reasons that nutrients
are generally present in very low concentrations, permanently consumed
by living organisms and...