Water pollution is defined as any adverse change in composition and condition of water which tend to lower its quality and cause health hazards or makes it unfit for domestic use. Water Pollution refers to the presence of impurities and harmful elements in the water. Polluted water can be a source of many deadly diseases that cause harm, diseases, and even kill humans. The polluted water is not fit for drinking and is harmful for living beings such as animals, birds etc.
Water Pollution contains chemicals, toxic substances, and germs that cause illness, such as cholera, dysentery, tuberculosis, and other abdominal related diseases in humans. It also carries worms such as roundworms and tapeworms that causes various diseases inside the human body.
Earth is the only planet to have water on its surface. About 71 per cent of earth’s surface is water covered and the oceans hold about 96 per cent of all earth’s water, only 2.5 per cent water we use for our essential things. The human body require nearly 3-liters water every day. Water is one of the very important elements of our life and the environment.
There are many reasons for water pollution. Some of the reasons directly cause water pollution and some indirectly. Many factories, industries etc dump contaminated water, chemicals and heavy metals into major waterways causing direct water pollution. One more reason for water pollution is the use of modern techniques in farms. Farmers apply nutrients such as phosphorus, nitrogen, potassium, in the form of chemical fertilizers, manure and sludge. It causes farms to discharge large quantities of agrochemicals, organic matter, saline drainage into water bodies, which indirectly causes water pollution.
There are many Sources of water pollution such as Sewage and domestic waste, Industrial wastes and effluents, insecticides and pesticides, Detergents and fertilisers, Siltation, Thermal pollution, Radioactive materials.
Industries produce a tremendous amount of waste, which contains toxic chemicals and pollutants, causing air pollution and subsequent damage to our environment and us. They contain harmful chemicals, including lead, mercury, sulphur, nitrates, asbestos, and many others.
Many industries, don’t have a proper waste management system and drain the waste in the freshwater, which goes into canals, rivers, and later into the sea. The toxic chemicals may change the colour of water, increase the number of minerals, called eutrophication, change the temperature of the water, and pose a severe hazard to aquatic creatures.
Chemical fertilizers and pesticides are used by farmers to protect crops from insects and bacterias. They are useful for the plant’s growth. However, when these chemicals are mixed up with water, they produce harmful pollutants for plants and animals. Also, when it rains, the chemicals mix up with rainwater and flow down into rivers and canals, which pose serious damages for aquatic animals.
All categories of sewage are likely to carry pathogenic organisms that can transmit disease to humans and animals. Sewage also contains organic matter that can cause odour and attract flies. Sewage contains nutrients that may cause eutrophication of receiving water bodies; and can lead to Ecotoxicity. Domestic water pollution is produced by discharge of domestic sludge containing organic substances and soaps.
Radioactive waste can endure in the environment for thousands of years, making safe disposal difficult. If improperly disposed of, it can enter the water, making it hazardous for humans, marine life, and the environment.
Mining is the process of crushing the rock and extracting coal and other minerals from the underground. These elements, when extracted in the raw form, contain harmful chemicals and can increase number of toxic elements when mixed-up with water, which may result in health problems. Mining activities emit a large amount of metal waste and sulphides from the rocks, which is harmful.
The transportation and storage of oil and its derivatives is subject to leakage, that pollutes our water resources. Oil pollution can occur when oil tankers spill their cargo. However, oil can also enter the sea via factories, farms, and cities, as well as via shipping industry.
Fossil fuels like coal and oil, when burnt, produce a substantial amount of ash in the atmosphere. The particles which contain toxic chemicals when mixed with water vapour result in acid rain. Also, carbon dioxide is released from the burning of fossil fuels, which results in global warming.
Water is an important element of human health and polluted water directly affects the human body. Water pollution causes various diseases like typhoid, cholera, hepatitis, cancer, etc. Water pollution damages the plants and aquatic animals present in the river by reducing the oxygen content from the water.
Drinking or consuming polluted water in any way has many disastrous effects on our health. It causes typhoid, cholera, hepatitis and various other diseases.
Chemicals in water bodies encourage the growth of algae. Bacteria feed this algae and this decreases amount of oxygen in the water body that effects the aquatic life.
It happens when toxins are pollutants enter in the water are consumed by aquatic animals (fish, shellfish etc.) which are then consumed by humans.
Chemicals accumulation and infusion in a water body, encourages growth of algae. The algae form a layer on top of the pond or lake. Bacteria feed on this algae and this event decreases the amount of oxygen in the water body, severely affecting the aquatic life.
(1) A person who ingests chemical toxins in their water can be at risk of Cancer, Hormone disruption, Altered brain function, damage to immune and reproductive systems, cardiovascular and kidney problems.
(2) Swimming in contaminated water can also trigger Rashes, Pink eye, Respiratory infections, Hepatitis etc.
(3) Nitrogenous chemicals are responsible for cancer and blue-baby syndrome.
(4) Several types of pathogens in water causes disease like jaundice, typhoid, amoebiasis etc.
(5) Hg poisoning (by consuming fish from Hg contaminated water) causes minamata disease.
(6) Excess of nitrate causes methemoglobinemia i:e., impairs O2, transport.
(7) Excess of fluorine cause a skeletal fluorosis i:e., deformity of teeth, painful and stiff joints. Maze is an indicator of fluorine pollution.
(8) Excess of arsenic causes black foot diseases. Its symptoms are peripheral neuritis, hyperkeratosis, lungs and skin cancer.
(9) Mortality rate due to cancer is higher in rural areas than urban areas because urban inhabitants use treated water for drinking while rural people don’t have facility of treated water and use unprocessed water. Poor people are at greater risk of disease due to improper sanitation, hygiene and water supply.
(10) Contaminated water has large negative effects in those women who are exposed to chemicals during pregnancy; it leads to the increased rate of low birth weight as a result fatal health is affected.
(11) Poor quality water destroys the crop production and infects our food which is hazardous for aquatic life and human life.
Following steps can be taken to control water pollution they are:
Various kinds of wastes should be treated before throwing them into water bodies so as to make them less harmful. Wastes which can be recycled should not be thrown and hence should be recycled to make useful things.
Sewage is the liquid waste or waste arising mainly from domestic and industrial sources. Sewage should be properly treated before discharged to water bodies.
Pesticides and fertilizers should be very judiciously used to avoid chemical pollution of water through agricultural farm run-offs. Bio-fertilizers and Bio-pesticides should be promoted.
Water pollution control board is concerned with matters relating to the prevention and control of water pollution. Central and state pollution control boards monitor the implementation of these legislation.
Environmental impact assessment of the new industries should be prepared with utmost care by environmentalists, scientists, to ensure minimum population of water bodies.
Various pollutants present in water body can be removed by appropriate methods such as absorption, Ion exchange, electro-dialysis, reverse osmosis etc.
State and union Government has enforced various acts to control water pollution.
This can be achieved by reducing waste input in water bodies.
Water pollution is a global issue and world community is facing worst situation due to polluted water. Major sources of water pollution are discharge of domestic and agriculture wastes, population growth, excessive use of pesticides and fertilisers and urbanisation. Bacterial, viral and parasitic diseases spread through polluted water and affect human health. It is recommended that there should be proper waste disposal system and waste should be treated before entering river or any water body. Educational and awareness programmes should be organised to control the pollution.