Pollution, also called environmental pollution, is the addition of any substance (solid, liquid, or gas) or any form of energy (such as heat, sound, or radioactivity) to the environment at a rate faster than it can be dispersed, diluted, decomposed, recycled, or stored in some harmless form.
Pollution is the process of making land, water, air or other parts of the environment unsafe and unsuitable to use. There is an undesirable change in the physical, chemical or biological characteristics of air, water and soil that may harmfully affect the life of human beings and other living organisms. Hazardous waste, toxic chemicals, suspended particles are affecting humans as well as animals. Many of the toxins, chemical and plastic have found their way in ecological food chain.
“Pollution“ means the direct or indirect discharge by man of substances or energy into the aquatic environment resulting in hazard to human health, harm to living resources and aquatic ecosystems, damage to amenities on interference with other legitimate use of water1).
Pollution is the presence in the environment of substances or contaminants that substantially alter or impair the usefulness of the environment2).
Pollution occurs, on the one hand, because the natural environment does not know how to decompose the unnaturally generated elements, i.e., anthropogenic pollutants, and, on the other, there is a lack of knowledge on the part of humans on how to artificially decompose these pollutants.
Pollution was not a serious problem as long as there was enough space available for each individual or group. However, with the establishment of permanent settlements by great numbers of people, pollution became a problem, and it has remained one ever since3).
The major kinds of pollution are air pollution, noise pollution, land pollution and water pollution. Pollutions of all kinds have negative effects on the environment and wildlife and often affect human health and well-being.
Air pollution refers to the release of harmful contaminants like chemicals, toxic gases, particulates, biological molecules, etc. into the earth’s atmosphere. A very common type of air pollution occurs when people release particles into the air by burning fuels. This pollution looks like soot, containing millions of tiny particles, floating in the air. Carbon monoxide, carbon dioxide, chlorofluorocarbons, aerosol sprays, etc., are some examples of air pollutants.
Polluted air results in smog increase, higher rain acidity, crop depletion from inadequate oxygen, and higher rates of asthma in the human beings. Researchers believe that climate change is also related to increased air pollution.
Noise pollution is the production of sounds that are irritating and have a high pitch as compared to the hearing capabilities of the people. The fundamental sources of noise pollution are heavy traffic on roads, airports, running of rails, manufacturing plants, construction or demolition of buildings and musical concerts etc.
There are direct links between noise and health, including stress-related illnesses, high blood pressure, speech interference and hearing loss.
According to the research conducted by the WHO, “noise pollution may contribute to hundreds of thousands of deaths per year by increasing the rates of coronary heart disease.”
Land or soil pollution is contamination of the soil. The addition of the contaminated particles to soil happens both due to the human and natural activities. Soil contamination occurs when chemicals are released by spill or underground leakage. Among the most significant soil contaminants are hydrocarbons, heavy metals, herbicides, pesticides and chlorinated hydrocarbons. The other factors leading to soil contamination include the landfill and illegal dumping, usually carried out in the outskirts of urban areas. In this process, the decomposed waste mixes with the nutrients present in the soil and leads to its depletion.
Water pollution happens when chemicals or dangerous foreign substances are introduced to water, including chemicals, sewage, pesticides and fertilizers from agricultural runoff, or metals like lead and mercury.
Increased use of non-degradable material, particularly the use of plastic is the main contributor in water pollution. Plastic materials such as bottles, carry bags, packaging material also find their way to water bodies, which adds to the water pollution and adversely affects its quality and aquatic life.
Toxic wastes released by industries, pathogens released in sewage, harmful chemicals present in agricultural runoffs, etc., are some of the top water pollutants. The contamination of water can lead to epidemics and even pandemics that can wipe out the population of an entire species.
According to the Environmental Protection Agency (EPA), 44 percent of assessed stream miles, 64 percent of lakes and 30 percent of bay and estuarine areas are not clean enough for fishing and swimming. According to United Nations, 783 million people do not have access to clean water and around 2.5 billion do not have access to adequate sanitation.
Coastal pollution, universally, is an emerging problem. As far as India is concerned, it has already become a serious environmental problem. Besides direct dumping of waste materials in the seas discharge through marine outfalls, large volumes of untreated or semi-treated wastes generated in various land-based sources/activities ultimately find way to the seas.
The coastal waters directly receive the inland waters, by way of surface runoff and land-drainage, laden with myriad of refuse materials. Apart from inputs from rivers and effluent-outfalls, the coastal areas are subject to intensive fishing, navigational activities, recreations, ports, industrial discharge and harbours, which are causative factors of water quality degradation to varying degrees. Contrary to the open sea, the changes in the quality of coastal waters are much greater due to river discharges under tidal conditions. Marine pollution is 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; impairing the quality for use of sea water and reduction of amenities4).
Uncontrolled disposal of land-based waste into the seas, through rivers and effluent outfalls, is a major cause of pollution of coastal waters. The coastal waters directly receive the inland waters, by way of surface runoff and land-drainage, laden with myriad of refuse materials, the rejects of wastes of the civilization. Apart from inputs from rivers and effluent-outfalls, the coastal areas are subject to intensive fishing, navigational activities, recreations, ports, industrial discharge and harbors, which are causative factors of water quality degradation to varying degrees. Contrary to the open sea, the changes in the quality of coastal waters are much greater due to river discharges under tidal conditions. Besides land drainage, there are large numbers of marine coastal outfalls discharging directly or indirectly industrial and municipal effluents into the seas5).
Radioactive pollution is the pollution caused by the release of radioactive substances in the atmosphere during activities such as nuclear explosions, mining of radioactive ores, etc. This type of pollution has risen in the 20th century with the countries engaged in the making of atomic and nuclear weapons.
Radioactive pollution can affect every aspect of the environment including air, water, and soil. It can also affect various objects such as buildings, machineries and equipments, which can retain radiation after massive exposure. This pollution results in birth defects, cancer, deteriorating health, even resulting in death. There are strict government regulations to control radioactive pollution.
The artificial warming of water is called thermal pollution. This pollution occurs when there is the use of water as a coolant in industries and disposal of heat generated in the process in the water. This results in an increase of temperature in that water. This makes the water hold less oxygen, which can kill fish and other creatures living in water. The worst impact of thermal pollution is witnessed in the aquatic systems where the level of dissolved oxygen is decreased by the abrupt increase in the water’s temperature.
Thermal pollution, according to Oishimaya Sen Nag, leads to the degradation of water quality, as the warm water does not provide ideal living conditions for aquatic flora and fauna. For example, when water used as a coolant in power plants or that used in industries is released into a natural water body, the warm or hot water mixes with the rest of the water to raise the overall temperature of the aquatic ecosystem. Higher temperatures also alter the composition of dissolved elements in water. The flora and fauna living in the area and adapted to a particular temperature range can be killed by this abrupt change in the water temperature.
Adv. Sunil Sharma is a writer for about 25 years and has authored more than 40 books on various subjects including Jurisprudence, Hindu Law and Environmental Laws.