Water pollution refers to contamination of water bodies. A 1969
United Nations report defined ocean pollution as:
"The introduction by man, directly or indirectly, of
substances or energy into the marine environment (including
estuaries) resulting in such deleterious effects as harm to living
resources, hazards to human health, hindrance to marine activities,
including fishing, impairment of quality for use of sea water and
reduction of amenities."
Two examples of different sources of water pollution are as
follows :
- Industrial Waste : They contain pollutants
such as lead, mercury, sulphur, asbestos, nitrates and many other
harmful chemicals. Many industries do not have proper waste
management system and drain the waste in the fresh water which goes
into rivers, canals and later in to sea. The toxic chemicals have
the capability to change the color of water, increase the amount of
minerals, also known as Eutrophication, change the temperature of
water and pose serious hazard to water organisms.
- Sewage and waste Water : The sewage water
carries harmful bacteria and chemicals that can cause serious
health problems. Pathogens are known as a common water pollutant;
The sewers of cities house several pathogens and thereby diseases.
Microorganisms in water are known to be causes of some very deadly
diseases and become the breeding grounds for other creatures that
act like carriers. These carriers inflict these diseases via
various forms of contact onto an individual. A very common example
of this process would be Malaria.