Environment Pollution

Learning Outcomes:

1. Understand key types of pollutants and their environmental impact.
2. Analyze causes and effects of air, water, soil, noise, thermal, and plastic pollution.
3. Evaluate control measures and government policies for pollution mitigation.
4. Explore concepts of pollutant classification based on origin, nature, and disposal.

Pollutants

Pollutants are materials or factors causing harmful effects on environmental quality. Common pollutants include smoke, chemicals, radioactive substances, household sewage, and discarded items.

Classification of Pollutants:

1. Based on Persistence in Environment:

• Primary Pollutants: Persist in their released form, e.g., DDT, plastic.
• Secondary Pollutants: Formed by interaction of primary pollutants, e.g., peroxyacetyl nitrate (PAN) from nitrogen oxides and hydrocarbons.

1. Based on Existence in Nature:

• Quantitative Pollutants: Occur naturally and become pollutants when exceeding threshold levels, e.g., carbon dioxide, nitrogen oxide.
• Qualitative Pollutants: Man-made pollutants not naturally occurring, e.g., fungicides, herbicides.

1. Based on Disposal Nature:

• Biodegradable Pollutants: Degraded by microbial action, e.g., sewage.
• Non-biodegradable Pollutants: Resistant to decomposition, e.g., plastics, heavy metal salts.

1. Based on Origin:

• Natural: From natural sources.
• Anthropogenic: Resulting from human activities.

Causes of Pollution:

1. Population Growth: Increased resource consumption.
2. Industrialization: Discharge of pollutants into the environment.
3. Urbanization: Overuse of land and water resources.
4. Nature Exploitation: Deforestation and overfishing.
5. Natural Events: Forest fires, volcanic eruptions, strong winds.

Air Pollution

Air pollution results from traffic, city expansion, economic development, and industrialization, releasing harmful substances into the atmosphere.

Major Air Pollutants:

1. Carbon Monoxide (CO): Colorless, odorless gas from incomplete burning of fuels, reducing oxygen in blood, leading to reflex impairment.
2. Carbon Dioxide (CO2): Main greenhouse gas from burning fossil fuels.
3. Chlorofluorocarbons (CFCs): Released from refrigeration, depleting the ozone layer.
4. Lead: Found in fuels, batteries, paints; causes nervous system damage and digestive issues.
5. Ozone: Ground-level pollutant from vehicle and industrial emissions; causes respiratory problems.
6. Nitrogen Oxides (NOx): Cause smog, acid rain, respiratory diseases.
7. Suspended Particulate Matter (SPM): Solids like smoke, dust; cause lung damage.
8. Sulfur Dioxide (SO2): From burning coal; causes lung diseases, contributes to smog and acid rain.

Smog

Smog combines fog and smoke, forming through the interaction of pollutants with sunlight, notably ground-level ozone. It hampers visibility, causes respiratory problems, and may lead to a rise in rickets due to reduced UV exposure.

Indoor Air Pollution

Indoor pollution involves physical, chemical, and biological pollutants within homes or institutions:

1. Rural Areas: Smoke from burning traditional fuels like wood, dung.
2. Urban Areas: From construction materials, household products, and poor ventilation.

Fly Ash

A byproduct of coal combustion in power plants, fly ash contains aluminum silicate, silicon dioxide, and heavy metals. It pollutes air, water, reduces plant yield, but can be utilized in construction, road-making, and reclamation of wastelands.

Effects of Air Pollution

1. Health Effects: Respiratory diseases, neurological damage, cancer.
2. Vegetation: Inhibits photosynthesis, causes chlorosis, metabolic inhibition.
3. Materials: Corrosion and decay of structures.
4. Aesthetic Loss: Decreased visibility and quality of life.

Control Measures for Air Pollution

1. Policy Enforcement: Zoning regulations, emission standards.
2. Preventive Measures: Efficient fuel use, industrial modifications.
3. Control of Particulate Matter: Use of arresters and scrubbers.
4. Automobile Emission Control: Efficient engines, catalytic converters, lead-free fuel.

Government Initiatives

1. National Air Quality Monitoring Programme: Monitors air quality nationwide.
2. National Ambient Air Quality Standards (NAAQS): Sets permissible pollutant levels.
3. National Air Quality Index (NAQI): Classifies air quality into categories with health implications.

Water Pollution

Defined as the addition of substances (organic, inorganic, radiological) to water bodies degrading their quality.

Sources:

1. Point Sources: Direct, identifiable sources, e.g., industrial discharge.
2. Diffuse Sources: Various, non-point sources, e.g., agricultural runoff.

Effects:

1. Aquatic Ecosystems: Reduces dissolved oxygen, eliminates sensitive species.
2. Human Health: Waterborne diseases, mercury poisoning, blue baby syndrome.
3. Groundwater Hazards: Nitrate, fluoride contamination causing health issues.

Control Measures:

1. Riparian Buffers: Vegetative barriers along water bodies.
2. Effluent Treatment: Sewage and industrial effluents before discharge.
3. Prevent Over-exploitation: Regulate groundwater usage.

Soil Pollution

The addition of substances adversely affecting soil quality, texture, or biological balance.

Causes:

1. Chemical Fertilizers: Overuse leads to salinity, reduced fertility.
2. Pesticides: Non-biodegradable chemicals accumulate in soil.
3. Solid Waste: Dumping of plastic, concrete, radioactive materials.

Effects:

1. Agriculture: Reduced fertility, crop yield.
2. Health: Groundwater contamination, bioaccumulation in food chain.
3. Urban Areas: Clogging drains, foul odors, waste management issues.

Control Measures:

1. Reduce Chemical Use: Organic farming, biofertilizers.
2. Solid Waste Treatment: Segregation, composting.
3. Afforestation: Reforestation to stabilize soil.

Noise Pollution

Defined as unpleasant noise disturbing human or animal life. Sources include traffic, construction, and machinery.

Impacts:

1. Annoyance: Causes irritation, restlessness.
2. Physiological Effects: Increases blood pressure, heart rate.
3. Hearing Loss: Prolonged exposure damages hearing.

Control:

1. Source Control: Maintenance of vehicles, prohibition of loudspeakers.
2. Transmission Path Control: Installation of barriers, green belts.
3. Protective Equipment: Ear protection, job rotation.

Important Note: The Indian Resource Panel is the first of its kind, preparing a roadmap for secondary resource utilization.

Thermal Pollution

Temperature change in natural water bodies due to human influence, mainly from industrial discharge.

Ecological Effects:

1. Warm Water: Reduces dissolved oxygen, disrupts aquatic life.
2. Cold Water: Affects fish eggs, river productivity.

Control Measures:

1. Cooling Towers: Before discharge, use cooling systems.
2. Cogeneration: Use excess heat energy in other processes.

Plastic Pollution

Marine resources face threats from plastic waste disrupting the food web. Plastic’s interference with phytoplankton affects marine ecosystems.

Important Note: “Science Express” is an innovative mobile science exhibition, raising environmental awareness.

MCQ:
Which of the following pollutants is mainly responsible for the depletion of the ozone layer?

1. Carbon Dioxide
2. Sulfur Dioxide
3. Chlorofluorocarbons
4. Nitrogen Oxides
   Answer: 3. Chlorofluorocarbons