Environmental Pollution - UPSC

Environmental Pollution

•  A substance that causes an undesirable change in the physical, chemical or biological characteristics of the natural environment is known as pollution. 

• Although there are some natural pollutants such as volcanoes, pollution generally occurs because of human activity. 

• Biodegradable pollutants, like sewage, cause no permanent damage if they are adequately dispersed.

• Non-biodegradable pollutants, such as lead (Pb), maybe concentrated as they move up the food chain.

• At present, Air Pollution- associated with basic industries such as oil refining, chemicals, iron and steel, and coal, as well as with internal combustion engine- is probably the principal offender, followed by water, and land pollution.

• Other forms of environmental pollution include noise and the emission of heat into waterways, which may damage aquatic life.

• Present-day problems of pollution include acid rain and the burning of fossil fuels to produce excessive carbon dioxide.

There are four types of environmental pollution which have been described briefly in the following:

• Air Pollution
• Water Pollution
• Soil and Land Pollution
• Noise Pollution

Air Pollution: 

Fig: Air Pollution

• The presence in the Earth's atmosphere of man-caused or man-made contaminants may adversely affect the property, or lives of plants, animals, or humans.

• Commonly air pollution includes CO₂, CO, Pb, NOx, O3 (Ozone), SOx, and smoke.

• The tremendous increase in vehicles during the last three decades in the country has increased air pollution, especially in large cities.

• Consequently, the urban population is suffering more by cough, nausea, irritation of the eyes, and various bronchial and visibility problems.

• Because of the emission of CO₂, CO, NOx, and suspended particles of lead (Pb) and heavy metals, the urban environment is more polluted than the rural environment.

• The air pollution is the main cause of many of the disease and ailments.

Air pollution has to lead the increase in the incidence of some of the disease like;

• Cough, shortness of breath, bronchitis, cold and fatigue, bronchopneumonia, lung infection, infection & anemia, high blood pressure, nervous system, emphysema, angina pectoris, fatal arrhythmia or myocardial damage, coronary damage, coronary disease, cancer in the kidney, testis, brain, stomach, lung, respiratory tract bladder & uterus, leukemia & problems associated with gastro-intestinal & liver damage.

Fig: Coronary Artery Disease (CAD)

Some of the important steps which can be helpful in reducing air pollution are:

• Reduction in vehicular emission
• Improvement in the quality of diesel and petroleum
• Use of alternate sources of fuel e.g., CNG (Compressed Natural Gas) & LPG (Liquid Petroleum Gas)
• More use of public transport
• Improved vehicular technology
• Mass awareness

Fig: Air Pollution Scrubber

Water Pollution:

Water is one of the most important requirements for human survival. Clean water is necessary for health & human development. Water pollution has been defined as the alteration of the physical, chemical, & biological properties of water, which may cause harmful effects on human & aquatic life. Unfortunately, over 70% of the available water in India is polluted. 

Fig: Water Pollution

The main causes of water pollution are:

Urbanization: 

• The unplanned growth of urban centers, especially inevitably lead to huge quantities of domestic and industrial waste. 

• The high energy consumption in urban places gives rise to large quantities of waste-water, sewage, and domestic trash. 

• The inadequate development of sewerage disposal has polluted most of the rivers, lakes, ponds, and wells.

• Municipal water treatment facilities in India are not up to the international standard.

• The quality of water is poor in the urban areas, especially in the unauthorized colonies & slums.

Industrialization:

• The industrial waste consists of chemicals, detergents, metal & synthetic compounds, besides the solid waste & garbage.

• These pollutants are generally discharged in rivers.

• Consequently, most of the rivers, lakes, ponds, and wells in India are polluted by industrial wastes.

Withdrawal of Water:

• The water of most of the rivers is utilized for irrigation, industries, & domestic purposes.

• In the plain areas, generally, the rivers contain little water during the winter & summer seasons.

• What flows into the rivers is the water merging from small streams & drains carrying untreated sewage & effluent.

• Rivers like the Yamuna River, for example, contain very little water near Delhi.

• Each river must contain a minimum discharge throughout the year to maintain its ecology.

Application of Plants Protection Chemicals:

• After the introduction of High Yielding Varieties in the agricultural landscape, the use of chemical fertilizers, insecticides & pesticides has increased substantially.

• These inputs can be used with success only in the areas where controlled irrigation is available. In fact, these chemicals have changed the soil chemistry. 

• The use of insecticides has killed the useful bacteria in the soil as well as the fertility-enhancing earthworms.

Ground-Water Quality:

• The underground water is largely consumed for irrigation, drinking, and industrial purposes.

• The underground water is being polluted by the heavy application of chemical fertilizers, plant protection chemicals, infiltration of contaminated water, & waste disposal.

• Once polluted, underground water may remain in hazardous conditions for decades or even for centuries.

Fig: Ground-water quality

Consequences of Water Pollution:

• Consumption of polluted water is a major cause of poor health in India. 

• The polluted water causes diseases like cholera, dysentery, diarrhea, jaundice & tuberculosis.

• About 80% of stomach diseases in India are water-borne.

• Children, especially in the urban slums & rural areas are the worst affected.

Soil & Land Pollution:

Fig: Soil & Land Pollution

• Soil is the life support system of mankind. Soil becomes polluter either due to the misdeed of man or at times by the environmental hazards.

• The main factors of soil & land pollution are soil erosion, excessive use of chemical fertilizers & plant protection chemicals.

• Soil is also polluted by liquid & solid wastes from urban & industrial areas, forest fires, water-logging, related capillary processes, & mining wastes.

• The soil pollution can be reduced by a judicious application of chemical fertilizers, insecticides, & pesticides.

• The urban & industrial effluents can be used for irrigation after proper treatment.

Noise Pollution:

Fig: Noise Pollution

• Noise is one of the important forms of atmospheric pollution.

• It may be defined as the state of discomfort & restlessness caused to humans by unwanted high-intensity sound.

• Noise pollution has increased in India considerably with the increase in urbanization & industrialization.

• The automobiles, factory machines, & loudspeakers at the religious places are the main noise pollutants.

• Noise pollution leads to impairment of hearing.

• It also results in mental tension, blood pressure, heart disease, irritation, fatigue, & stomach trouble.

Noise pollution can be reduced by:

• Locating the noise-producing industries away from the residential areas
• Replacement of old machinery
• Minimum use of horn
• Improvement in rail tracks, &
• To educate the younger generation about the adverse consequences of noise pollution.