Module 78. Pollution and Pollution Control

Pollution is one of the most pressing environmental challenges of the modern era. It refers to the introduction of harmful substances or energy into the environment that adversely affect living organisms, ecosystems, and natural resources. As industrialisation, urbanisation, and population growth accelerate, the intensity and diversity of pollutants have increased, posing serious threats to human health and ecological stability. Effective pollution control has therefore become a key component of environmental management and sustainable development in India and across the world.

Concept and Types of Pollution

Pollution may occur naturally or as a result of human activities, but anthropogenic pollution has become dominant since the Industrial Revolution. Pollutants can be solid, liquid, or gaseous substances that alter the physical, chemical, or biological properties of air, water, or soil. The main types of pollution include:
1. Air PollutionAir pollution arises from the emission of gases and particulates into the atmosphere beyond permissible limits. Major pollutants include sulphur dioxide (SO₂), nitrogen oxides (NOₓ), carbon monoxide (CO), particulate matter (PM₂.₅ and PM₁₀), lead, and volatile organic compounds (VOCs).
Sources:

• Industrial emissions from thermal power plants, refineries, and manufacturing units.
• Vehicular exhaust, especially from diesel engines.
• Burning of fossil fuels, crop residue, and biomass.
• Construction dust and open waste burning.

Effects: Air pollution causes respiratory illnesses (asthma, bronchitis), cardiovascular diseases, and eye irritation. It contributes to acid rain, smog formation, and global warming. Long-term exposure affects vegetation and damages historical monuments, as seen in the case of the Taj Mahal in Agra.
2. Water PollutionWater pollution refers to the contamination of surface or groundwater with biological, chemical, or physical pollutants. It disrupts aquatic ecosystems and renders water unsafe for human use.
Sources:

• Industrial effluents containing heavy metals, dyes, and chemicals.
• Domestic sewage discharge into rivers and lakes.
• Agricultural runoff carrying fertilisers and pesticides.
• Oil spills and marine litter.

Effects: It leads to diseases like cholera, dysentery, and typhoid, affects aquatic biodiversity, and causes eutrophication—excessive nutrient enrichment resulting in algal blooms. Rivers such as the Ganga and Yamuna have been severely affected by industrial and domestic waste.
3. Soil PollutionSoil pollution involves the accumulation of toxic chemicals, salts, and waste materials that degrade soil quality.
Sources:

• Excessive use of pesticides, herbicides, and chemical fertilisers.
• Industrial waste dumping and mining operations.
• Disposal of non-biodegradable waste such as plastics and electronic scrap.

Effects: It reduces soil fertility, affects crop productivity, and leads to bioaccumulation of harmful substances in the food chain.
4. Noise PollutionNoise pollution results from unwanted or harmful sounds exceeding acceptable levels, typically measured in decibels (dB).
Sources:

• Traffic, railways, and airports.
• Industrial operations and construction activities.
• Loudspeakers, urban congestion, and social events.

Effects: Continuous exposure to high noise levels causes hearing loss, stress, insomnia, hypertension, and reduced concentration.
5. Radioactive PollutionRadioactive pollution is caused by the release of nuclear substances and radiation from atomic energy plants, nuclear testing, or improper disposal of radioactive waste.
Effects: Radiation exposure can lead to genetic mutations, cancer, and ecosystem damage lasting for centuries. Incidents such as the Chernobyl Disaster (1986) and Fukushima (2011) highlight the catastrophic potential of nuclear contamination.
6. Thermal and Light PollutionThermal pollution occurs when industrial units discharge heated water into water bodies, altering temperature and oxygen balance. Light pollution, prevalent in urban areas, disturbs nocturnal wildlife and human circadian rhythms.

Pollution Status in India

India faces severe pollution challenges, particularly in urban and industrial regions. According to the World Air Quality Report (2024), several Indian cities rank among the world’s most polluted due to high particulate concentrations. The Central Pollution Control Board (CPCB) identifies the Ganga, Yamuna, and Sabarmati as critically polluted river stretches. Industrial belts, mining zones, and urban sprawls contribute significantly to air, water, and soil degradation.
The main causes of rising pollution in India include rapid industrialisation, vehicular growth, energy demand, population expansion, and weak enforcement of environmental laws.

Pollution Control Measures

Pollution control involves a combination of technological, regulatory, and behavioural strategies to reduce emissions and prevent environmental degradation. India has established a comprehensive framework of laws, policies, and institutions to combat pollution.
1. Legal and Institutional Framework

• The Water (Prevention and Control of Pollution) Act, 1974: First major legislation for controlling water pollution and establishing State Pollution Control Boards (SPCBs).
• The Air (Prevention and Control of Pollution) Act, 1981: Regulates air pollution sources and sets emission standards.
• The Environment (Protection) Act, 1986: A comprehensive umbrella law enacted after the Bhopal Gas Tragedy, empowering the government to take measures for environmental protection.
• The Noise Pollution (Regulation and Control) Rules, 2000: Specify permissible noise levels for different zones.
• The Hazardous Wastes (Management and Handling) Rules, 1989 (amended): Regulate disposal and recycling of hazardous materials.

Institutions such as the Central Pollution Control Board (CPCB) and State Pollution Control Boards (SPCBs) monitor compliance, enforce standards, and promote cleaner technologies.
2. Policy and Programme Initiatives

• National Clean Air Programme (NCAP), 2019: Targets a 40% reduction in particulate pollution by 2026 in over 130 non-attainment cities.
• National River Conservation Plan (NRCP): Aims to reduce pollution and improve water quality in major rivers.
• Namami Gange Programme (2014): Integrates sewage treatment, riverfront development, and public participation to rejuvenate the Ganga.
• National Green Tribunal (NGT): A judicial body established in 2010 for speedy resolution of environmental disputes.
• Swachh Bharat Mission (2014): Promotes sanitation, waste management, and reduction in open defecation.

3. Technological and Industrial Measures

• Adoption of clean and renewable energy sources such as solar, wind, and hydroelectric power.
• Installation of effluent treatment plants (ETPs) and common sewage treatment plants (CSTPs) in industrial zones.
• Implementation of zero-liquid discharge (ZLD) systems to recycle wastewater.
• Use of electrostatic precipitators, scrubbers, and bag filters in factories to reduce air emissions.
• Promotion of green building technologies, electric vehicles (EVs), and biofuels.

4. Waste Management Strategies
Effective waste management forms an integral part of pollution control.

• Solid Waste Management Rules, 2016: Mandate segregation of waste at source and promote recycling.
• Plastic Waste Management Rules, 2016 (amended 2022): Ban on single-use plastics and promotion of extended producer responsibility (EPR).
• E-Waste Management Rules, 2016: Regulate collection, recycling, and safe disposal of electronic waste.

5. Community and Individual Actions
Public awareness and community involvement are critical for pollution prevention. Initiatives like tree plantation drives, clean-up campaigns, and environmental education promote sustainable lifestyles. Non-governmental organisations (NGOs) such as Centre for Science and Environment (CSE) and TERI play active roles in research, advocacy, and awareness.
Citizens can contribute by:

• Reducing vehicle use and conserving energy.
• Avoiding plastic products and promoting recycling.
• Adopting green consumer habits and waste segregation.

Emerging Challenges

Despite extensive measures, pollution control in India faces challenges such as inadequate infrastructure, weak enforcement, and limited public participation. Rapid urbanisation, electronic waste, and industrial expansion outpace regulatory capacity. Climate change and transboundary pollution further complicate management.
Additionally, new forms of pollution such as microplastic contamination, nanoparticle emissions, and digital pollution from data centres demand updated regulatory approaches.

Sustainable Strategies for Pollution Control

Future strategies must integrate technological innovation, policy coherence, and public participation