Pollution

Pollution is the introduction of harmful materials into the environment. These harmful materials are called pollutants. Pollutants can be natural, such as volcanic ash, or can be created by human activity, such as trash or runoff produced by factories. Pollutants damage the quality of air, water, and land.

(i) Types and Sources of Pollution; Major Pollutants

Air Pollution

Air pollution is the contamination of air due to the presence of substances in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or to materials.

• Sources and Pollutants:
  • Vehicular: Release of pollutants like carbon monoxide (CO), nitrogen oxides (NOx), hydrocarbons, and particulate matter from cars, trucks, and buses.
  • Industrial: Emissions from factories and power plants, including sulfur dioxide (SO2), nitrogen oxides, and particulate matter.
  • Burning Garbage: Releases smoke, ash, and harmful gases like dioxins and furans.
  • Brick Kilns: Emit black carbon, sulfur dioxide, and particulate matter.

Water Pollution

Water pollution is the contamination of water bodies, usually as a result of human activities.

• Sources and Pollutants:
  • Household Detergents: Phosphates from detergents can cause eutrophication (excessive growth of algae) in water bodies.
  • Sewage: Untreated or inadequately treated sewage contains organic matter, bacteria, and viruses that can contaminate water.
  • Industrial Waste: Factories release a variety of pollutants, including heavy metals (like lead and mercury), chemicals, and solvents.
  • Oil Spills: Accidental release of oil from tankers and offshore rigs can have devastating effects on marine life.

Thermal Pollution

Thermal pollution is the degradation of water quality by any process that changes ambient water temperature. A common cause is the use of water as a coolant by power plants and industrial manufacturers.

Soil Pollution

Soil pollution is the contamination of soil with harmful substances.

• Sources and Pollutants:
  • Industrial Waste: Solid and liquid waste from industries can contaminate the soil with toxic chemicals.
  • Urban Commercial and Domestic Waste: Garbage and other solid waste from homes and businesses.
  • Chemical Fertilizers and Pesticides: Excessive use of these chemicals in agriculture can degrade soil quality and contaminate groundwater.

Biomedical Waste

Biomedical waste is any kind of waste containing infectious (or potentially infectious) materials. It may also include waste associated with the generation of biomedical waste that visually appears to be of medical or laboratory origin.

• Examples: Used and discarded needles, syringes, soiled dressings, body parts, diagnostic samples, blood, chemicals, pharmaceuticals, medical devices, and radioactive materials.

Radiation Pollution

Radiation pollution is the increase in the natural radiation levels caused by human activities.

• Sources:
  • X-rays: Medical and dental X-rays are a source of radiation exposure.
  • Radioactive Fallout from Nuclear Plants: Accidents at nuclear power plants can release radioactive materials into the environment.

Noise Pollution

Noise pollution is the disturbing or excessive noise that may harm the activity or balance of human or animal life.

• Sources:
  • Motor Vehicles: Traffic noise from cars, motorcycles, and trucks.
  • Industrial Establishments: Noise from machinery and equipment in factories.
  • Construction Sites: Noise from construction activities like drilling and excavation.
  • Loudspeakers: Use of loudspeakers at public events and religious gatherings.

(ii) Biodegradable and Non-biodegradable Wastes

Biodegradable Wastes

• Meaning: Wastes that can be broken down into simpler, harmless substances by the action of microorganisms like bacteria and fungi.
• Examples: Paper, vegetable peels, food scraps, wood, and cotton.

Non-biodegradable Wastes

• Meaning: Wastes that cannot be broken down by microorganisms and persist in the environment for a long time.
• Examples: Plastics, glass, Styrofoam, synthetic fibers, and pesticides like DDT (Dichlorodiphenyltrichloroethane).

(iii) Effects of Pollution and Control Measures

Effects of Pollution

• Greenhouse Effect and Global Warming: The trapping of heat by greenhouse gases (like CO2) in the atmosphere, leading to a gradual increase in the Earth's average temperature (global warming). This causes climate change, rising sea levels, and extreme weather events.
• Acid Rain: When pollutants like sulfur dioxide and nitrogen oxides react with water in the atmosphere, they form acids that fall to the Earth as acid rain. Acid rain damages forests, soils, and aquatic ecosystems.
• Ozone Layer Depletion: The thinning of the ozone layer in the stratosphere due to the release of chemicals like chlorofluorocarbons (CFCs). The ozone layer protects us from the sun's harmful ultraviolet (UV) radiation.

Measures to Control Pollution

• Use of Unleaded Petrol / CNG: Using unleaded petrol and Compressed Natural Gas (CNG) in vehicles reduces the emission of harmful pollutants.
• Switching off Engines at Traffic Signals: This simple practice helps to reduce fuel consumption and air pollution.
• Social Forestry: Planting trees on a large scale helps to absorb carbon dioxide and reduce air pollution.
• Setting up Sewage Treatment Plants: Treating sewage before it is discharged into water bodies helps to reduce water pollution.
• Ban on Polythene and Plastics: Reducing the use of plastic bags and other single-use plastics helps to reduce plastic pollution.
• Organic Farming: Using natural fertilizers and pesticides instead of chemical ones helps to reduce soil and water pollution.
• Euro/Bharat Vehicular Standards: Implementing stricter emission standards for vehicles helps to reduce air pollution.

Swachh Bharat Abhiyan

"Swachh Bharat Abhiyan" (Clean India Mission) is a national campaign launched by the Government of India in 2014 to clean up the streets, roads, and infrastructure of India's cities, towns, and rural areas. The campaign aims to achieve the vision of a 'Clean India' by 2nd October 2019, the 150th birth anniversary of Mahatma Gandhi.