Chapter 6: Pollution and Conservation Methods PDF

🍃 Chapter 6: Pollution and Conservation Methods Pollution The addition/release of undesirable physical, chemical, or biological agents (substances/pollutants) into the environment due to human (anthropogenic) activities....

🍃 Chapter 6: Pollution and Conservation Methods Pollution The addition/release of undesirable physical, chemical, or biological agents (substances/pollutants) into the environment due to human (anthropogenic) activities. Types of Pollution Based on Source 1. Point Source Pollution Definition: Pollution caused by the discharge of effluents at a specific point. Characteristics: Easy to treat. Effluent can be traced to a single source. Example: Sewage outlets. 2. Non-Point Source Pollution Chapter 6: Pollution and Conservation Methods 1  Definition: Pollution caused by the discharge of effluents over a wide area. Characteristics: Difficult to treat. Diffuse and cannot be traced to a single source. Example: Roads. Construction sites. Runoff water from fields. Air Pollution Presence of solid, liquid, or gaseous substances, including radiation, in the atmosphere at concentrations that may be injurious to organisms and environmental processes. Classification of Air Pollutants 1. Primary Pollutants Definition: Pollutants that remain in the same form when added to the environment. Example: DDT. 2. Secondary Pollutants Definition: Pollutants formed by the interaction of primary pollutants. Example: Peroxyacetyl nitrate (PAN) formed by the interaction of nitrogen oxides and hydrocarbons. 3. Quantitative Pollutants Definition: Natural substances that become pollutants when their concentration exceeds a threshold level. Example: Carbon dioxide, Nitrogen oxide. 4. Qualitative Pollutants Chapter 6: Pollution and Conservation Methods 2  Definition: Human-made substances that are pollutants. Example: Fungicides, Herbicides, DDT. Particulate Pollutants Definition Particulate Pollutants: Matter suspended in the air, such as dust and soot. Characteristics 1. Size Range: 0.001 to 500 μm in diameter. Particles larger than 10 μm settle down. Particles less than 0.02 μm form persistent aerosols. 2. Health Impact PM 2.5: Causes respiratory issues, inflammation, and pneumoconiosis. According to CPCB, PM 2.5 (particles ≤ 2.5 μm) causes the most significant harm to human health. Types of Particulate Pollutants 1. PM 2.5 (≤ 2.5 μm) Size: 30 times finer than human hair. Major Components: Arsenic, Nickel. Health Impact: Can cause respiratory symptoms, inflammation, and cancer. Nickel compounds are carcinogenic. Sources: Emissions from combustion processes in power plants and vehicles. 2. PM 1 (≤ 1 μm) Size: 70 times finer than human hair. Sources: Vehicular and industrial emissions. Chapter 6: Pollution and Conservation Methods 3  Health Impact: Contains more toxins (including metals), causes lung injury, gene damage, and cancer. 3. PM 10 (≤ 10 μm) Size: Small enough to pass through the throat and nose, entering the lungs. Health Impact: Can cause heart and lung problems, leading to serious health effects. Fly Ash Definition Fly Ash: By-product ejected mainly by thermal power plants during coal burning. Environmental Impact 1. Pollution Air and water pollution due to ejection into the environment. Causes heavy metal pollution in water bodies. Affects crops and vegetation due to direct deposition on leaves. 2. Toxicity Heavy Metals: Lead, mercury, cadmium, arsenic, cobalt, and copper. Oxides: Aluminium oxide, silicate, silicon dioxide (SiO2), calcium oxide (CaO). Composition Main Components: Silica, alumina, oxides of iron, calcium, magnesium. Toxic heavy metals such as lead, mercury, cadmium, arsenic, cobalt, and copper. Oxides present in large quantities: Aluminium, Silicate, SiO2, CaO. Chapter 6: Pollution and Conservation Methods 4  Uses of Fly Ash 1. Construction Can replace up to 35% cement, reducing construction costs. Used as fill material for road embankments, concrete roads, and abandoned mines. 2. Environmental Applications Reclamation of wastelands. Increases crop yield when added to soil, enhances soil water-holding capacity. Impact on crops: If deposited on leaves, reduces photosynthesis. Policy Measures by MoEF Mandatory Use of Fly Ash-based Products: In all construction projects, road embankment works, low-lying landfilling within 100 km radius of thermal power stations. Minefilling activities within 50 km radius of power stations. Nanoparticles (NPs) Definition Dimensions: ~1/10^9 meter (nanometer scale). Natural Sources: Forest fires, volcanic eruptions, weathering, dust storms, etc. Properties: Heterogeneous in size. Transported over long distances and remain suspended in the air for days. Characteristics 1. Large Surface Area to Volume Ratio Chapter 6: Pollution and Conservation Methods 5  React rapidly in the atmosphere. Consequences include visibility reduction and impacts on climate. Applications 1. Electronics: Used in nanodevices and circuits. 2. Targeted Drug Delivery: Applied in medical treatments. Environmental Effects 1. Dust Cloud Formation Contains soot and black carbon (NP), deposited on Himalayan glaciers. Reduces albedo: Decreased reflection of sunlight, leading to increased melting of glaciers. 2. Reduction in Troposphere’s Pollutant Scrubbing Capacity NPs bind with hydroxyl radicals (OH). Reduces the atmosphere's natural ability to clean pollutants. 3. Ozone Depletion Increased free radical production (e.g., Chlorine) depletes ozone. 4. Stratospheric Cooling NPs and molecular hydrogen rise to the stratosphere. Increased water vapour leads to formation of stratospheric clouds (mostly ice crystals), which destroy ozone. Black Carbon (Soot) Definition Type: Solid, short-lived air pollutant. Source: Released from incomplete combustion at high temperatures. Characteristics Chapter 6: Pollution and Conservation Methods 6  1. Absorption of Sunlight Most robust absorber of sunlight. Heats the air directly. 2. Albedo Reduction After deposition on snow, darkens the surface, causing direct heating. Reduces albedo, accelerating melting of snow and ice. Environmental Impact 1. Regional Effects: Disrupts cloudiness and monsoon rainfall patterns. 2. Global Impact: Contributes to climate change by absorbing heat and warming the atmosphere. Largest Emitters 1. India (especially the Indo-Gangetic plain). 2. China. Brown Carbon 1. Source: Emitted mainly from the combustion of organic matter (biomass combustion). Carbon Monoxide (CO) Definition Short life in the atmosphere (a few months). Burns with a blue flame, producing carbon dioxide. Sources 1. Natural Sources: Chapter 6: Pollution and Conservation Methods 7  Photochemical reactions in the troposphere. Volcanoes. Forest fires. 2. Anthropogenic Sources: IC engine exhaust. Partial combustion of fuels. Iron smelting. Health Effects Poisoning due to poor ventilation or heat management (e.g., electronics). Toxic when concentration > 35 ppm. Combines with hemoglobin to form carboxyhemoglobin, impairing oxygen transport. Environmental Effects 1. Tropospheric Ozone Formation: Contributes to the formation of tropospheric ozone (a pollutant). 2. Increased Methane Concentration: Elevates methane levels, a greenhouse gas (GHG). Carbon Dioxide (CO2) Definition Colourless & odourless gas. Heavier than air. Sources 1. Natural Sources: Volcanoes. Chapter 6: Pollution and Conservation Methods 8  Hot springs and geysers. Carbonate rocks (by dissolution in water and acids). Found in groundwater, rivers, lakes, ice caps, glaciers, and seawater (due to water solubility). Health Effects Asphyxiant gas when concentrations exceed 7%. May lead to suffocation in high concentrations. Environmental Effects 1. Global Warming: CO2 is a greenhouse gas contributing to global warming. 2. Ocean Acidification: Dissolves in water to form carbonic acid, leading to ocean acidification. Ozone (O3) Presence in the Atmosphere Volume: 0.00005% by volume of the atmosphere. Unevenly distributed across different layers. Types of Ozone 1. Good Ozone (Stratospheric Ozone): Formed in the stratosphere when O2 interacts with UV radiation. Absorbs harmful UV rays from the sun, protecting life on Earth. 2. Bad Ozone (Tropospheric Ozone): Forms at ground level. Pollutant, short-lived GHG, and toxic. Chapter 6: Pollution and Conservation Methods 9  Some is transported from the stratosphere; rest is formed when CO, NO2, and VOC react in the presence of sunlight, converting O2 to O3. Harmful Effects of Ozone Smog formation. Irritates eyes (itchy and watery eyes). Affects sensitive vegetation and ecosystems, especially forests during the growing season. Transported over long distances by wind, leading to high O3 levels in rural areas too. Stratospheric Ozone Depleting Substances (ODS) Definition Human-made gases that release chlorine or bromine atoms when exposed to UV rays. These atoms destroy stratospheric ozone. Examples of ODS 1. Chlorofluorocarbons (CFCs): Used in refrigeration, air conditioning, and aerosols. 2. Hydrochlorofluorocarbons (HCFCs): Replaced CFCs in some applications but still harmful. 3. Hydrobromofluorocarbons (HBFCs): Used in fire extinguishers. 4. Halons: Primarily used in fire extinguishers. 5. Methyl Bromide: Chapter 6: Pollution and Conservation Methods 10  Used as a fumigant for pest control. 6. Carbon Tetrachloride: Previously used in fire extinguishers and cleaning solvents. 7. Methyl Chloroform: Used in aerosols, as a solvent for organic compounds, and for cleaning metals and circuit boards. Nitrogen Oxides (NOx) Sources 1. IC Engines: 2. Coal-burning Power Plants: 3. Lightning: 4. Agricultural Fertilisation: 5. Nitrogen-fixing Plants: Effects on Health and Environment 1. Health Impacts: Contributes to respiratory issues, including asthma and other lung diseases. 2. Environmental Impacts: Acid Rain: NOx reacts with water and oxygen to form nitric acid, leading to acid rain. Tropospheric Ozone: NOx, along with volatile organic compounds (VOCs), forms ozone at ground level, which is harmful to human health and the environment. Photochemical Smog: Formation of smog due to the reaction of NOx and VOCs in the presence of sunlight. Chapter 6: Pollution and Conservation Methods 11  Sulphur Dioxide (SO2) Characteristics Nature: Toxic gas with a pungent, irritating smell. Sources: 1. Natural: Released during volcanic activity. 2. Anthropogenic: Thermal Power Plants: Burning of coal and diesel fuels. Industrial Processes: Paper production. Metal smelting (e.g., copper). Ore Roasting: Sulphide ores like pyrite, sphalerite, and cinnabar. Health Effects Classified as a poisonous air pollutant. Leads to: Stroke risk. Heart disease. Lung cancer. Environmental Impact Major contributor to air pollution. Precursor to acid rain, which harms ecosystems and corrodes infrastructure. Global Context India's Role: Leading SO2 emitter worldwide (as of 2019). Chapter 6: Pollution and Conservation Methods 12  Electricity generation from coal contributes significantly. Polyaromatic Hydrocarbons (PAHs) Sources Incomplete Combustion: Organic materials. Cigarette smoke. High-temperature cooking. Industrial Production: Naphthalene: Used commercially in the US for making chemicals and mothballs. Properties Toxicity: Mutagenic (causes genetic mutations). Carcinogenic (cancer-causing). Lipid Solubility: Highly lipid soluble; absorbed readily in mammals through the gastrointestinal tract. Leads to bioaccumulation in living organisms. Environmental & Health Effects Associates with Particulate Matter: Binds with PM2.5 and PM10, increasing their toxicity. Health Hazards: Long-term exposure impacts respiratory and cellular health. Volatile Organic Compounds (VOCs) Chapter 6: Pollution and Conservation Methods 13  Definition Carbon-based chemicals that evaporate quickly at room temperature. Examples: Formaldehyde, benzene, ethylene glycol, methylene chloride, tetrachloroethylene, toluene, xylene, 1,3-butadiene. Sources 1. Primary Indoor Sources: Household Products: Perfumes, hair sprays, furniture polish, glues. Others: Air fresheners, moth repellents, wood preservatives. 2. Specific Chemicals: Ethylene: Used in agriculture for fruit ripening. Natural plant hormone. Formaldehyde: Natural decay product from plant material in soil. Combustion product (e.g., tobacco smoke). Health Effects 1. Short-Term: Irritation: Eyes, nose, and throat. Headaches, nausea, and loss of coordination. 2. Long-Term: Liver damage. Exposure to specific VOCs (e.g., ethylene - headaches and drowsiness; formaldehyde - carcinogenic risks). Chapter 6: Pollution and Conservation Methods 14  Applications Ethylene: Used as a ripening agent. Formaldehyde: Fungicide, germicide, and disinfectant. Preservative in mortuaries and labs. Benzene Definition Found in crude oil; an elementary petrochemical. Present in cigarette smoke and as a natural source from volcanoes and forest fires. Uses 1. Industrial Applications: Manufacturing: Plastics, resins, synthetic fibers, rubber, lubricants. 2. Fuel Component: High octane number makes it an essential part of gasoline. Health and Environmental Effects 1. Health: Carcinogenic: Increases the risk of cancer. Bone Marrow Failure: Affects the production of blood cells. 2. Environment: Reacts with air pollutants to form ground-level ozone: Damages crops and materials (via smog formation). Chapter 6: Pollution and Conservation Methods 15  Benzene-Related Pollutants (VOCs & PAHs) 1. Toluene (Methylbenzene): Uses: Paint thinners, octane booster in gasoline engines. 2. Xylene (Dimethylbenzene): Uses: Solvent in the printing, rubber, and leather industries. 3. Styrene: Uses: Raw material for polystyrene (used in refrigerators, automotive parts, etc.). Incident: Styrene gas leak in LG Polymers chemical factory (Visakhapatnam, 2020) caused fatalities. Lead Sources 1. Petrol and Diesel: Tetraethyl lead (TEL): Anti-knock agent for smoother vehicle performance. 2. Industrial and Consumer Products: Lead batteries. Paints and hair dyes. Health Effects 1. Severe Health Risks: Kidney and Liver Damage. Interference with RBC Development. Nervous System Damage. 2. Cumulative Poisoning: Chapter 6: Pollution and Conservation Methods 16  Persistent accumulation in the body. 3. Other Impacts: Digestive issues. Increased risk of cancer. Child Development: Lowers intelligence levels in children. Environmental Concerns Lead contamination persists in the environment due to its non- biodegradable nature. Ammonia Properties 1. Physical Characteristics: Corrosive and colourless. Pungent odour. 2. Natural Emissions: Decaying organic matter. Human and animal waste. Anthropogenic Sources 1. Livestock Management: Manure decomposition. 2. Agricultural Practices: Use of nitrogen-based fertilisers. Health Effects 1. Toxicity: Poisonous and irritates eyes, nose, and throat. Chapter 6: Pollution and Conservation Methods 17  2. Particulate Matter Formation: Combines with sulphates/nitrates to form ammonium salts (secondary PM2.5). Environmental Effects 1. Water Pollution: Highly soluble in water. Causes nitrification and eutrophication. 2. Aquatic System Impact: Promotes algal blooms and oxygen depletion, harming aquatic life. Asbestos Definition A group of 6 naturally occurring silicate fibrous minerals: 1. Chrysotile 2. Crocidolite 3. Amosite 4. Anthophyllite 5. Tremolite 6. Actinolite Health Effects 1. Prolonged Inhalation: Fibers lodge in the lungs, causing damage over time. 2. Diseases: Lung Cancer: Caused by chronic exposure. Mesothelioma: Cancer of the lining of the lungs or abdomen. Chapter 6: Pollution and Conservation Methods 18  Asbestosis: A type of pneumoconiosis; scarring of lung tissue leading to breathing difficulties. Key Characteristics Durable and heat-resistant. Commonly used in construction, insulation, and fireproofing materials. Metallic Oxides Definition Oxides of metals formed during mining operations and metallurgical processes. Released as dust or fine particulate matter. Adverse Effects 1. On Plants: Dust deposition on leaves obstructs photosynthesis. Causes physiological disorders: Stunted growth. Reduced nutrient uptake. Leads to biochemical changes: Altered enzyme activity. Results in developmental issues: Poor flowering and fruiting. Contributes to reproductive failure in plants. 2. On Environment: Soil contamination. Toxicity to aquatic and terrestrial ecosystems. Chapter 6: Pollution and Conservation Methods 19  Examples of Metallic Oxides Iron Oxide (Fe2O3): Common in mining dust. Aluminium Oxide (Al2O3): Impacts soil fertility. Zinc Oxide (ZnO): Toxic at high concentrations. Copper Oxide (CuO): Can harm microorganisms in soil. Biological Pollutants 1. Definition: Particles of biological origin that cause pollution and health issues. 2. Examples: Pollen from plants. Mites. Pet hair. Fungal spores. Parasites. Certain bacteria. 3. Health Impacts: Trigger asthma and other allergic diseases. Long-term exposure worsens respiratory conditions. 4. Sources: Plants, pets, and decaying organic matter. Radon 1. Definition: A naturally occurring radioactive gas. 2. Source: Chapter 6: Pollution and Conservation Methods 20  Released from soil and rocks containing uranium. 3. Impact of Poor Ventilation: Modern, airtight houses trap radon indoors. 4. Health Effects: Prolonged exposure leads to lung cancer. 5. Prevention: Improve ventilation in homes. Use radon detectors for monitoring. Air Pollution - Causes and Key Sources 1. Vehicular and Industrial Emissions Major Pollutants (>80%): NOx, CO, SOx, Non-Methane Volatile Organic Compounds (NMVOCs). Trace Emissions: CH4, CO2, SOx, and Total Suspended Particles (TSPs). Industries Contributing to Pollution: Iron & steel, cement, paper, sugar, fertilizer, copper, aluminum (SPM, SOx, NOx, CO2). 2. Pyrolysis Definition: Decomposition of synthetic material at high temperatures (300-400°C) without oxygen. Applications: Methanol, activated carbon, synthetic gas for electricity, bio-crude fuel from COVID-19 PPE kits. Advantages: Reduces waste in landfills, GHG emissions, water pollution. Chapter 6: Pollution and Conservation Methods 21  Concerns: Incomplete combustion, toxic gas exposure, fire hazards. 3. Fuel Adulteration Mixing kerosene with gasoline/diesel. Increases emissions: CO, NOx, and SPM. 4. Agriculture, Waste Treatment, and Biomass Burning Critical Pollutants: Ammonia (NH3), Methane (CH4), Nitrous Oxide (N2O). Landfill and Wastewater Emissions: Methane. 5. Stubble Burning Effects: Air pollution, smog, loss of soil fertility, reduced moisture. 6. Indoor Air Pollution Sources: Burning of coal, charcoal, animal dung, wood, kerosene. Pollutants: PM2.5, black carbon, CO2, CO, methane, VOCs. 7. Volcanism Emissions: SO2 (acid rain), aerosols (ozone destruction), CO2, hydrogen fluoride, hydrogen sulfide. Chapter 6: Pollution and Conservation Methods 22  Smog (Smoke + Fog) - Causes and Effects 1. Causes of Smog Primary Pollutants: Burning of coal, vehicular emissions, industrial fumes. Soot particulates, Ozone (O3), Carbon Monoxide (CO), Sulphur Dioxide (SO2), Nitrogen Dioxide (NO2), and others. 2. Types of Smog Sulphurous Smog (London Smog): Caused by high concentrations of sulphur oxides in the air. Resulting from the use of sulphur-bearing fossil fuels (particularly coal). Aggravated by damp conditions and high suspended particulate matter. Photochemical Smog (Summer Smog / Los Angeles Smog): Occurs in urban areas with high vehicular emissions. Forms when Nitrogen Oxides (NOx) and Volatile Organic Compounds (VOCs) react in the presence of sunlight. Causes light brownish color in the atmosphere, reduced visibility, plant damage, eye irritation, and respiratory distress. 3. Chemical Reactions in Photochemical Smog Formation: NO + VOC = NO2 (Nitrogen Dioxide) NO2 + UV (sunlight) = NO + O (atomic oxygen) O + O2 = O3 (Ozone) NO2 + VOC = PAN (Peroxyacetyl Nitrate – C2H3NO5) Resulting Compounds: Ozone (O3), PAN, and other oxidants like Hydroxyl radicals (OH). 4. Effects of Photochemical Smog Chapter 6: Pollution and Conservation Methods 23  Health & Environment: Reduced visibility, eye irritation, respiratory distress. Damage to plants. Temperature inversion, which worsens smog conditions. Reduced precipitation. Acid Rain and Acidification - Causes and Effects 1. Definition of Acid Rain Acid Rain: Any precipitation with a pH < 5.6, making it more acidic than usual. 2. Formation of Acid Rain Key Reactions: Nitrogen Oxides (NOx): Nitrogen reacts with oxygen at high temperatures and pressures (in lightning bolts, power plants, or internal combustion engines). Forms Nitric Oxide (NO) and Nitrogen Dioxide (NO2). Nitrogen Dioxide reacts with water in the rain to form Nitric Acid (HNO3). Nitrates: Can be used by plants as a nutrient. 3. Gases that Cause Acid Rain Sulphur Oxides (SOx) Emitted primarily from burning coal and other sulfur-containing materials. Nitrogen Oxides (NOx) Includes NO, NO2, and N2O. Chapter 6: Pollution and Conservation Methods 24  Formed during high-temperature reactions like combustion. 4. Effects of Acid Rain Environmental Impact: Degrades water quality, leading to the acidification of aquatic ecosystems. Damages soil, plant life, and buildings. Health Hazards from Occupational Lung Diseases 1. Black Lung Disease (Pneumoconiosis / Anthracosis) Cause: Inhalation of coal dust over many years. Common in: Coal industry workers. Symptoms: Accumulation of coal dust in the lungs. Lungs appear black instead of healthy pink. Health Impact: Chronic lung disease leading to difficulty breathing and potential long-term disability. 2. Silicosis Cause: Inhalation of silica dust over extended periods. Common in: Quarrying, manufacturing, and construction workers. Symptoms: Shortness of breath. Persistent cough, fever, and bluish skin. Health Impact: Progressive, incurable lung disease. Can lead to permanent physical disability. Chapter 6: Pollution and Conservation Methods 25  3. Pneumoconiosis Cause: Inhalation of dust leading to interstitial lung fibrosis. Common in: Mining, construction, mica, and textile industry workers. Symptoms: Shortness of breath, persistent cough. Health Impact: A general term for lung diseases caused by dust inhalation. Affects tissue around the alveoli, leading to chronic lung issues. 4. Byssinosis Cause: Exposure to cotton dust in poorly ventilated environments. Common in: Yarn and fabric manufacturing industry workers. Symptoms: Cough, chest tightness, shortness of breath. Health Impact: Occupational lung disease, worsening with prolonged exposure. 5. Asbestosis Cause: Prolonged exposure to asbestos fibers. Common in: Asbestos industry workers. Symptoms: Chronic cough, shortness of breath. Chest pain, fatigue. Health Impact: Chronic lung inflammation. Leads to serious diseases like lung cancer, pleural mesothelioma, and peritoneal mesothelioma. Measures to Control Industrial Pollution 1. Filters Chapter 6: Pollution and Conservation Methods 26  Purpose: Removes particulate matter from the gas stream. Example: Baghouse filtration system. Application: Used in various industries to clean emissions and reduce airborne particles. 2. Electrostatic Precipitators Purpose: Removes particulate matter using an electrostatic charge. Applications: Furnaces. Thermal power plants. Cement factories. Steel plants. Function: Efficiently collects fine particulate matter by applying electrical charges. 3. Inertial Collectors Purpose: Collects heavier particles through centrifugation. Mechanism: Uses inertial forces to separate particles based on their size and weight. 4. Scrubbers Purpose: Wet collectors that remove aerosols and gaseous pollutants. Function: Collects wet particles on a surface. Particles are wetted by a scrubbing liquid. Application: Used to remove gases like sulfur dioxide (SO₂). Types: Wet scrubbers (often used in industrial exhaust systems). 5. Catalytic Converters Purpose: Reduces the emission of harmful gases in automobiles. Chapter 6: Pollution and Conservation Methods 27  Function: Converts toxic gases into less harmful emissions. Requirement: Unleaded petrol is needed to prevent inactivation of the catalyst by lead. Application: Installed in motor vehicles to control air pollution. Pollution Index to Control Industrial Pollution 1. Pollution Index (PI) Range: 0 to 100 Purpose: Categorizes industrial sectors based on pollution levels. Goal: Encourages adoption of cleaner technologies by providing a clear pollution scale. 2. White Category Pollution Index: Up to 20 Number of industries in India: 36 Criteria: Practically non-polluting industries. Requirements: No Environmental Clearance (EC) needed. No Consent to Operate required. Must inform State Pollution Control Board (SPCB) & Central Pollution Control Board (CPCB). Examples: Air cooler or air conditioning units. Chalk factories. Biscuit tray units. 3. Green Category Chapter 6: Pollution and Conservation Methods 28  Pollution Index: 21 to 40 Number of industries in India: 63 Description: Moderately polluted industries. Examples: Aluminum utensils manufacturing. Steel furniture manufacturing. Soap manufacturing. Tea processing. 4. Orange Category Pollution Index: 41 to 59 Number of industries in India: 83 Description: Severely polluted industries. Examples: Coal washeries. Glass manufacturing. Paint manufacturing. Stone crushers. Aluminum and copper extraction from scrap. 5. Red Category Pollution Index: 60+ Number of industries in India: 60 Description: Critically polluted industries. Examples: Cement manufacturing. Petrochemicals. Pharmaceuticals. Chapter 6: Pollution and Conservation Methods 29  Sugar production. Paper and pulp manufacturing. Nuclear power plants. Organic chemicals production. Fertilizers. Firecracker production. Restriction: No Red category industries allowed in ecologically fragile/protected areas. Coal Gasification 1. Definition Process: Coal is partially oxidized with air, oxygen, steam, or carbon dioxide. Outcome: Production of a fuel gas known as syngas or producer gas. Uses: Used as a substitute for natural gas, methane, etc., for energy production. 2. Benefits Cleaner Energy: One of the cleanest methods to convert coal into electricity, hydrogen, and other energy products. Reduces emissions of harmful gases: Carbon monoxide (CO) Carbon dioxide (CO2) Sulphur dioxide (SO2) Waste Reduction: Gasification of waste reduces landfill space. Chapter 6: Pollution and Conservation Methods 30  Decreases methane emissions. Reduces fossil fuel dependence. 3. Applications Syngas: After cleaning, syngas can be used for: Producing Synthetic Natural Gas (SNG) like methane (CH4). Creating liquid biofuels, such as synthetic diesel. 4. India’s Target Goal: 100 million tonnes (MT) of coal gasification by 2030. Vehicle Scrappage Policy 2021 1. Key Provisions Government Vehicles: All central and state government vehicles over 15 years old to be scrapped starting April 1, 2023. Private Vehicles: Private cars over 20 years old to be de-registered and scrapped. Commercial Vehicles: Commercial vehicles over 15 years old to be de-registered and scrapped. 2. Objectives Reduce Pollution: Aim to decrease emissions from older vehicles, improving air quality. Promote Clean Mobility: Encourage the adoption of cleaner, newer vehicles. Boost Recycling: Chapter 6: Pollution and Conservation Methods 31  Promote vehicle recycling and the reuse of components. 3. Implementation Scrapping Incentives: Financial incentives for vehicle owners to scrap old vehicles and purchase new ones. Testing Centers: Establishment of automated fitness centers to test vehicles' condition. Policy Enforcement: Strong enforcement to ensure compliance, with penalties for non- compliance. 4. Expected Outcomes Environmental Benefits: Reduction in vehicular pollution and carbon emissions. Economic Benefits: Boost to the automobile sector with increased sales of new vehicles. Creation of new jobs in the vehicle recycling industry. Bharat Stage (BS) Norms 1. Introduction Purpose: Introduced by the Government of India (GoI) to regulate air pollution from motor vehicles. Limits emissions of pollutants like nitrogen oxides (NOx), carbon monoxide (CO), hydrocarbons, particulate matter (PM), and sulphur oxides (SOx). Launched in 2000. Chapter 6: Pollution and Conservation Methods 32  2. BS VI Norms (2020) Transition: BS IV to BS VI: Skipped BS V norms to leapfrog directly to BS VI (inspired by Euro 6 standards in Europe) to meet carbon footprint goals. Objective: To reduce pollution levels and improve vehicle emissions. 3. Advantages of BS VI Pollution Reduction: Particulate Matter (PM) from diesel cars: Reduced by 80%. Nitrogen Oxides (NOx): Reduced by 70% in diesel cars and 25% in petrol cars. Fuel Improvements: Reduction in sulphur content enables use of better catalytic converters. Technology and Diagnostics: Onboard diagnostics become mandatory for all vehicles. New measurement standards for particulate matter based on number rather than mass. 4. Concerns Cost Implications: Higher technological investment required, making BS VI vehicles more expensive for consumers. Electric Mobility 1. Government Push for Electric Vehicles Target: Chapter 6: Pollution and Conservation Methods 33  India aims to go fully electric by 2030. NITI Aayog proposes banning internal combustion (IC) engine powered two-wheelers by 2025 and three-wheelers by 2023. 2. FAME India Scheme (Phase II) Full Form: Faster Adoption and Manufacturing of Electric & Hybrid Vehicles. Objective: Promote localization of electric vehicle (EV) parts. Create market demand: 10 lakh e-2Ws (electric two-wheelers). 5 lakh e-3Ws (electric three-wheelers) in the next 3 years. 3. Benefits of FAME India Scheme Incentivizes the adoption and manufacturing of electric and hybrid vehicles. Supports the transition from fossil fuels to electric mobility in India. EV Charging Guidelines to Encourage EV Adoption: 1. Phases of EV Charging Infrastructure Expansion Phase 1 (1-3 years): Coverage: Mega cities with a population of 4 million+. Existing highways connecting these cities. Phase 2 (3-5 years): Coverage Expansion: Big cities such as state capitals and Union Territory (UT) headquarters. Chapter 6: Pollution and Conservation Methods 34  2. Nodal Agency Bureau of Energy Efficiency (BEE): Statutory body under the Ministry of Power. Responsible for overseeing the implementation of the guidelines. Electric Vehicle Charging Guidelines and Specifications 1. Urban Charging Infrastructure Grid Requirement: At least one charging station in a grid of 3x3 km in cities. 2. Highway Charging Infrastructure Standard Charging Stations: Charging stations every 25 km along highways. Fast Charging Stations: Fast charging stations every 100 km on both sides of highways. 3. Private Charging Management: Private charging stations at residences/offices managed by DISCOMs (Distribution Companies). 4. Public Charging Stations (PCS) De-licensed Activity: Anyone can set up a Public Charging Station (PCS). Flexibility: PCS can install chargers based on market demand. Chapter 6: Pollution and Conservation Methods 35  Tax-Related Norms for Electric Vehicles 1. Tax Incentives Income Tax Exemption: ₹1.5 lakh exemption for purchasers of electric vehicles (EVs) in Budget 2019-2020. Reduced GST: EVs GST reduced from 12% to 5%. Chargers and Charging Stations: GST reduced from 18% to 5%. 2. Green Tax on Old Vehicles Principle: Based on the principle of “polluters must pay”. Levy Conditions: Imposed when commercial vehicles obtain fresh fitness certificates or private vehicles seek renewal of registration. 3. Additional Tax by State Governments State Tax: States can levy an additional tax on top of regular road taxes. 4. Revenue Use Revenue Allocation: Revenue collected through these taxes is used for: Tackling pollution. Setting up state-of-the-art facilities for emission monitoring. Polluters Pay Principle Chapter 6: Pollution and Conservation Methods 36  1. Definition Polluters Bear the Cost: The principle proposes that those who produce pollution must bear the costs of managing it to prevent harm to human health and the environment. 2. Global Context Part of Sustainable Development Principles: It is a part of the 1992 Rio Declaration, which outlines principles to guide sustainable development worldwide. National Clean Air Program (NCAP, 2019) 1. Overview First National-Level Strategy: Aimed at reducing air pollution (PM2.5 and PM10) across India. Target: 40% reduction by 2026 (from 2017 levels). 2. Execution and Legal Status Executed by: Central Pollution Control Board (CPCB). Legal Backing: Operates under the Air (Prevention and Control of Pollution) Act, 1981. Not notified under any specific Act, thus lacks strong legal mandate. 3. Air Quality Standards Acceptable Limits: PM 2.5: 40 μg/m³ (annual standard). PM 10: 60 μg/m³ (annual standard). 4. Key Objectives Chapter 6: Pollution and Conservation Methods 37  Expand Air Quality Monitoring Network: Increase the number of monitoring stations across the country. Build Capacity: Strengthen air pollution management at national, state, and local levels. Public Awareness: Educate citizens about the dangers of air pollution. 5. Focus Cities Non-Attainment Cities: Covers 132 cities that have not met National Ambient Air Quality Standards for over 5 years. 6. Monitoring Platform PRANA Portal: A portal for monitoring and regulating air pollution in non-attainment cities. CPCB (Central Pollution Control Board) 1. Constitution Statutory Body: Established under the Water (Prevention and Control of Pollution) Act, 1974. 2. Functions and Responsibilities Pollution Control: Monitor and control water and air pollution across India. Regulations: Enforce regulations for preventing and controlling pollution. Chapter 6: Pollution and Conservation Methods 38  Data Collection: Collect and maintain data on water and air quality. Implementation: Assist in the implementation of environmental laws and policies. National Air Quality Monitoring Programme (NAQMP) 1. Objective Purpose: Assess ambient air quality across India. Determine trends and status of air pollution. Ensure compliance with National Ambient Air Quality Standards (NAAQS). Identify non-attainment cities (cities failing to meet air quality standards). Understand natural cleaning processes in the atmosphere. Undertake corrective measures to reduce air pollution. 2. Monitoring Parameters Air Pollutants: Sulphur Dioxide (SO2) Oxides of Nitrogen (NO2) Respirable Suspended Particulate Matter (RSPM / PM10) Fine Particulate Matter (PM2.5) Additional Monitoring: Wind speed and wind direction Relative humidity (RH) and temperature Chapter 6: Pollution and Conservation Methods 39  National Ambient Air Quality Standards (NAAQS) 1. Development and Authority Developed by: Central Pollution Control Board (CPCB) Legal Framework: Conferred power under the Air (Prevention and Control of Pollution) Act, 1981 2. Applicability Nationwide: The NAAQS is applicable across the entire country, ensuring uniform standards for air quality monitoring and control. 2021 WHO Air Quality Guidelines (AQGs) 1. Overview Reflects updated research on how air pollution impacts human health, revealing that damage occurs at lower concentrations than previously understood. 2. Key Pollutants PM 2.5 / PM 10: Fine particulate matter Oxygen Nitrogen Dioxide (NO2) Sulphur Dioxide (SO2) Carbon Dioxide (CO2) 3. Applicability to India Non-binding: These guidelines are not legally enforceable. Current Impact: They do not immediately impact India as the National Ambient Air Quality Standards (NAAQS) in the country do not meet WHO’s existing guidelines. Chapter 6: Pollution and Conservation Methods 40  SAFAR System for Monitoring Air Pollutants 1. Overview SAFAR (System of Air Quality and Weather Forecasting and Research) is a national initiative by the Ministry of Earth Sciences (MoES). Developed by the Indian Institute of Tropical Meteorology (IITM), Pune, and operationalized by the India Meteorological Department (IMD). 2. Pollutants Monitored PM1, PM2.5, PM10: Particulate matter Ozone Carbon Monoxide (CO) Nitrogen Oxides (NOx): NO, NO2 Sulphur Dioxide (SO2) Black Carbon (BC) Methane (CH4) Non-methane Hydrocarbons (NMHC) Volatile Organic Compounds (VOC’s) Benzene Mercury 3. Features Provides real-time air quality index (AQI) on a 24x7 basis with colour- coding. 72-hour advance forecast of air quality. Measures weather parameters: temperature, rainfall, humidity, wind speed, wind direction, UV radiation, and solar radiation. 4. AQI Classification Good: 0-50 Chapter 6: Pollution and Conservation Methods 41  Satisfactory: 51-100 Moderate: 101-200 Poor: 201-300 Very Poor: 301-400 Severe: 401-500 National Air Quality Index (AQI) 1. Overview Launched by the Ministry of Environment, Forest and Climate Change (MoEF) in April 2015 under the Swachh Bharat initiative. Purpose: To help citizens assess the air quality within their vicinity. 2. AQI Categories Good: 0-50 Satisfactory: 51-100 Moderately Polluted: 101-200 Poor: 201-300 Very Poor: 301-400 Severe: 401-500 3. Pollutants Considered PM10 (Particulate Matter) PM2.5 (Fine Particulate Matter) NO2 (Nitrogen Dioxide) SO2 (Sulphur Dioxide) CO (Carbon Monoxide) O3 (Ozone) NH3 (Ammonia) Chapter 6: Pollution and Conservation Methods 42  Pb (Lead) Measures to Control Air Pollution in NCR 1. Environment Pollution (Prevention and Control) Authority Established: 1998 by MoEF under the Environment Protection Act, 1986, as a Supreme Court-appointed body. Mandate: Prevent and control environmental pollution in the National Capital Region (NCR) and enforce the Graded Response Action Plan (GRAP). 2. Graded Response Action Plan (GRAP) Severe+ or Emergency (PM2.5 > 300 μg/m³ or PM10 > 500 μg/m³ for 48+ hours) Stop entry of trucks (except for essential commodities). Stop construction work. Odd/even scheme for private vehicles. Severe (PM2.5 > 250 μg/m³ or PM10 > 430 μg/m³) Close brick kilns, hot mix plants, and stone crushers. Maximise power generation from natural gas instead of coal. Mechanised cleaning of roads and sprinkling of water. Very Poor (PM2.5 > 120 μg/m³ or PM10 > 350 μg/m³) Stop the use of diesel generator sets. Apartment owners discouraged from burning fires in winter. Poor (PM2.5 > 60 μg/m³ or PM10 > 100 μg/m³) Heavy fines for garbage burning; enforce pollution control regulations in brick kilns & industries. Mechanised sweeping and water sprinkling on roads. Strict enforcement of the ban on firecrackers. 3. Other Measures Chapter 6: Pollution and Conservation Methods 43  Ban on old vehicles within the city by the National Green Tribunal (NGT). Open burning has been largely curtailed. Completion of Eastern and Western Peripheral Expressways to reduce traffic congestion for vehicles not destined for Delhi. Measures to Reduce Stubble Burning 1. PUSA Decomposer Composition: A mix of fungal solution, jaggery, and gram flour. Function: To be sprinkled on the stubble, facilitating its bio-degradation within 20 days, thus reducing the need for burning. 2. Super SMS and Happy Seeders Super SMS (Super Stubble Management Systems) Purpose: Helps chop the stubble and spread it evenly across the field, making it easier to manage without burning. Happy Seeder Purpose: Facilitates direct sowing of wheat without the need to clear the stubble, thus preventing stubble burning. Smog Towers Purpose: Large-scale air purifiers designed to clean the air of pollutants. Technology: Fitted with multiple layers of carbon nanofiber air filters to remove pollutants as the air passes through. Green Crackers 2019 SC Mandate: The Supreme Court mandated the use of green crackers for Diwali to reduce air pollution. Traditional Firecrackers: Made with pollutants like barium nitrate and antimony (90% of crackers are made in Sivakasi, TN). Chapter 6: Pollution and Conservation Methods 44  SC Ban on Barium Nitrate: The use of barium nitrate, a major pollutant in crackers, was banned. NEERI's Innovation: The National Environmental Engineering Research Institute (NEERI), part of CSIR, developed an alternative formula by substituting barium nitrate with potassium nitrate and zeolite. This change helps reduce PM10 and PM2.5 emissions by 30%. Emissions Trading Scheme (ETS) by Gujarat Gujarat’s Emissions Trading Scheme (ETS) Launch: Gujarat government introduced the Emissions Trading Scheme (ETS) for trading in particulate matter emissions. Uniqueness: Unlike other pollution control mechanisms, ETS focuses on particulate matter emissions rather than greenhouse gases (GHGs). Comparison with Other Systems: Clean Development Mechanism (CDM): Allows trading in carbon credits (under the Kyoto Protocol). European Union Emission Trading System (EU ETS): Targets GHG emissions. India's Energy Trading Scheme: Run by the Bureau of Energy Efficiency for trading energy units (e.g., launched in Surat). Objective: The ETS aims to reduce pollution and minimize the cost of compliance for industries. Flue-Gas Desulfurization (FGD) Systems Purpose: Removes acidic gases, particularly sulfur dioxide (SO2) and HCl, from flue gases (gases expelled from exhaust pipes). Technologies Used: Wet Scrubbing: Involves the use of water to remove contaminants. Chapter 6: Pollution and Conservation Methods 45  Dry Scrubbing: Uses dry reagents (such as lime) to absorb pollutants. Main Chemical: Lime is typically used in both wet and dry scrubbing processes to neutralize the acidic gases. The Ozone Depleting Substances (ODS) Rules 1. Overview Jurisdiction: Framed under the Environment (Protection) Act, the ODS Rules regulate the production, trade, import, and export of Ozone Depleting Substances (ODS). ODS Covered: Includes substances such as CFCs, halons, carbon tetrachloride, methyl chloroform, and methyl bromide. Objective: Set deadlines for the phasing out of various ODS to protect the ozone layer. 2. HCFCs as Interim Substitutes Interim Use: HCFCs (Hydrochlorofluorocarbons) serve as substitutes for CFCs, allowed until 1st January 2040. Phase-out of HCFC-141b: HCFC-141b is primarily used in foam manufacturing to produce rigid polyurethane (PU) foams. Sectors Affected: This substance is critical in industries related to buildings, cold storage, cold chain infrastructure, and commercial refrigeration. Prohibition: The production and import of HCFC-141b is prohibited under the Ozone Depleting Substances (Regulation and Control) Amendment Rules, 2019. 3. Ozone Depleting and Global Warming Potentials (GWP) Ozone Depleting Global Warming Substance Potential (ODP) Potential (GWP) Chapter 6: Pollution and Conservation Methods 46  Chlorofluorocarbons (CFCs) High High (both ODS & GHG) Hydrochlorofluorocarbons Low High (GHG) (HCFCs) Hydrofluorocarbons (HFCs) Zero High (GHG) HydrofluoroOlefin (HFO) Zero Very Low WATER POLLUTION 1. Definition The presence of undesirable substances or pollutants in water that degrade its quality, making it unfit for use. 2. Types of Pollutants 1. Organic Pollutants: Includes waste from plants, animals, and human activities (e.g., sewage, pesticides). 2. Inorganic Pollutants: Includes heavy metals (e.g., lead, mercury) and chemicals (e.g., nitrates, phosphates). 3. Biological Pollutants: Pathogens like bacteria, viruses, and parasites that can cause diseases. 4. Radiological Pollutants: Radioactive substances from nuclear waste, mining, or testing activities. 5. Thermal Pollution: Increase in water temperature due to industrial discharge, reducing oxygen levels and affecting aquatic life. 3. Impacts Health Risks: Waterborne diseases such as cholera, dysentery, and typhoid. Ecosystem Damage: Loss of aquatic biodiversity. Economic Loss: Affects industries like fishing and tourism. Reduced Usability: Decreases availability of safe drinking water. Chapter 6: Pollution and Conservation Methods 47  4. Sources Point Sources: Discharge from factories, sewage treatment plants, and oil spills. Non-point Sources: Runoff from agricultural lands, urban areas, and forests. 5. Prevention & Control Wastewater Treatment: Effective treatment of sewage and industrial effluents. Legislation: Enforcement of water pollution control laws. Awareness: Promoting responsible water use and waste disposal. MEASURING POLLUTION LOAD IN WATER 1. Dissolved Oxygen (DO) Definition: Level of free oxygen in water essential for aquatic organisms. Optimal Levels: DO < 8.0 mg/L: Indicates contamination. DO < 4.0 mg/L: Indicates high pollution. Factors Affecting DO: Surface Turbulence: Enhances oxygen absorption. Photosynthetic Activity: Produces oxygen. Consumption: By aquatic organisms and organic matter decomposition. Waste Presence: Organic/inorganic pollutants reduce DO. 2. Biological Oxygen Demand (BOD) Definition: Oxygen consumed by microorganisms to decompose organic matter in water. Measurement: Milligrams of oxygen per litre (mg/L). Indicators: Chapter 6: Pollution and Conservation Methods 48  High BOD = High pollution (biodegradable waste). Low DO = Often accompanies high BOD. Limitations: Limited to biodegradable materials; not fully reliable for overall water pollution measurement. 3. Chemical Oxygen Demand (COD) Definition: Measures total oxygen required to oxidize organic and oxidizable inorganic compounds. Key Points: Includes biodegradable and non-biodegradable substances. Expressed in parts per million (ppm). Importance: Provides a more comprehensive understanding of water pollution compared to BOD. Summary DO: Indicates contamination or pollution. BOD: Highlights pollution from biodegradable wastes. COD: Assesses total pollution (organic + inorganic). Industrial Waste and Water Contamination 1. Key Pollutants in Industrial Waste Heavy Metals: Commonly discharged metals include: Mercury Cadmium Copper Lead Chromium Arsenic Chapter 6: Pollution and Conservation Methods 49  Toxic to human health and ecosystems even in small quantities. Organic Compounds: Include chemicals from industrial solvents, pesticides, and plastics, contributing to long-term contamination. 2. Key Findings from the Central Water Commission (CWC) Report Most Common Contaminant: Iron was identified as the most prevalent contaminant in water bodies affected by industrial discharge. 3. Environmental and Health Impacts Heavy Metals: Bioaccumulation in aquatic life, affecting the food chain. Toxicity leading to neurological, cardiovascular, and developmental disorders in humans. Organic Compounds: Persistent in the environment, some act as endocrine disruptors or carcinogens. Thermal and Radiation Pollution 1. Thermal Pollution Cause: Primarily caused by the release of heated water from industries such as power plants (thermal power stations) into natural water bodies. Effects: Decrease in Dissolved Oxygen: Higher water temperatures reduce the capacity of water to hold oxygen, which is essential for aquatic life. Fish and Aquatic Animal Mortality: Sudden temperature rises can cause thermal shock, killing fish and other aquatic organisms. Chapter 6: Pollution and Conservation Methods 50  Disruption of Ecosystem: Warmer waters alter the habitat of various species, potentially leading to the loss of biodiversity. 2. Radiation Pollution Cause: Occurs when nuclear accidents or natural disasters (e.g., tsunamis, earthquakes) lead to radiation leakage into nearby water bodies. Effects: Radiation Exposure: Contaminated water may cause long-term health effects on humans, including cancer, genetic mutations, and organ damage. Impact on Aquatic Life: Radiation harms aquatic organisms by disrupting biological processes and causing mutations, which can lead to population declines and biodiversity loss. Mining and Water Pollution 1. Water Usage and Chemical Contamination Cause: Mining operations require large amounts of water, and chemicals like cyanide, sulphuric acid, and mercury are used for processes like extraction and processing. Effects: These chemicals can easily contaminate surrounding ground and surface water, leading to severe environmental and health risks for nearby communities and ecosystems. 2. Acid Rock Drainage (ARD) Cause: ARD is a natural process that occurs when sulphides in rocks are exposed to water. Effects: Chapter 6: Pollution and Conservation Methods 51  Sulphuric Acid Production: Sulphuric acid is generated, which accelerates the weathering of rocks and leads to the leaching of harmful minerals and metals into nearby water sources. Environmental Damage: The increase in acidity lowers the pH of water, which can be harmful to aquatic life and degrade water quality. 3. Acid Mine Drainage (AMD) Cause: AMD is a more intense version of ARD, caused by the excavation of large quantities of rock containing sulphide minerals, typically in open- pit or underground mining. Effects: Accelerated Leaching: The process of leaching is intensified in low pH conditions, releasing toxic substances like heavy metals (e.g., arsenic, lead) into water sources. Ecological Impact: The acid and toxins severely harm aquatic ecosystems and can lead to the destruction of biodiversity in affected areas. Groundwater and Drinking Water Contamination 1. Salinity Contamination in Rajasthan Cause: Rajasthan has the highest number of rural areas affected by salinity in groundwater, primarily caused by natural processes and human activities like irrigation and industrial use. Effects: High salinity in water negatively affects both drinking water quality and agricultural productivity, leading to health risks for the population. 2. Nitrates Chapter 6: Pollution and Conservation Methods 52  Cause: Excessive nitrate contamination often comes from agricultural runoff, especially from the use of fertilizers. Effects: Methemoglobinemia (Blue Baby Syndrome): Nitrate in drinking water impairs oxygen transport in infants, leading to suffocation-like symptoms and potentially fatal outcomes. 3. Arsenic Cause: Arsenic contamination can be both natural (from geological formations) and anthropogenic (from agricultural, industrial, and mining activities). Effects: Health Risks: Chronic exposure leads to severe health issues like Black Foot Disease, diarrhoea, lung cancer, and skin cancer. Geographic Prevalence: High levels of arsenic are found in groundwater, especially in the Ganges Delta (India and Bangladesh). 4. Cadmium Cause: Cadmium enters drinking water through industrial discharge and agricultural runoff. Effects: Itai Itai Disease: A painful condition affecting bones and joints. Cancer: Long-term exposure to cadmium can cause lung and liver cancer. 5. Fluorides Cause: Fluoride contamination often comes from natural sources, but over- extraction of groundwater accelerates its presence in drinking water. Chapter 6: Pollution and Conservation Methods 53  Effects: Health Risks: Fluorides cause neuromuscular disorders, gastrointestinal issues, teeth deformities, skeletal fluorosis, and Knock-Knee Syndrome (bone deformity). 6. Uranium Cause: Uranium naturally occurs in soil and rocks, especially in regions with alluvial aquifers (e.g., Rajasthan) or crystalline rocks like granite (e.g., Telangana). Effects: Health Risks: Prolonged exposure to uranium in drinking water can lead to kidney toxicity and other renal issues. 7. Radioactive Radon Cause: Radon is a radioactive gas emanating from granite and uranium deposits as part of natural radioactive decay. Effects: Lung Cancer: Radon exposure through air and water damages lung tissues and increases the risk of lung cancer. Kidney Cancer: Uranium contamination, especially in groundwater, may lead to kidney cancer. 8. Freshwater Salinization Syndrome (FSS) Cause: FSS occurs when salty runoff from agricultural and industrial activities contaminates freshwater ecosystems. Effects: FSS causes the salinization of freshwater bodies, which disrupts aquatic life and reduces water quality for drinking and irrigation. Chapter 6: Pollution and Conservation Methods 54  Sewage Water Contamination 1. Composition of Sewage Water Sources: Domestic Sewage: Includes wastewater from households, containing human and animal excreta, food residues, cleaning agents, and detergents. Hospital Sewage: Often contains pathogens, pharmaceuticals, and hazardous chemicals. Contents: Pathogenic microbes, organic matter, chemicals, and pharmaceuticals are commonly found in sewage water, making it a serious public health risk if not treated properly. 2. Ammonia Pollution in Sewage Cause: Ammonia in sewage water primarily comes from the breakdown of nitrogen-containing compounds in human waste, food residues, and animal excreta. Effects: Health Risk: Ammonia in drinking water poses a danger to human health, especially at concentrations higher than the acceptable limit. BIS Standards: The acceptable limit of ammonia in drinking water, as per the Bureau of Indian Standards (BIS), is 0.5 ppm. Ammonia concentrations above this limit can cause toxic effects, including respiratory problems and damage to the liver and kidneys. Agricultural Water Contamination 1. Agricultural Runoff Chapter 6: Pollution and Conservation Methods 55  Sources: Water runoff from agricultural fields carries dissolved salts, toxic metal ions, organic compounds, and chemicals. Common Contaminants: Potassium, ammonia, toxic metals, and organic chemicals from agricultural activities. 2. Fertilizers Key Components: Nitrogen, Phosphorus, and Potassium are the primary elements in fertilizers. Impact: Excessive use of fertilizers leads to nutrient pollution. Groundwater Contamination: Fertilizers can leach into groundwater, causing eutrophication (overgrowth of algae) in water bodies, which depletes oxygen levels and harms aquatic life. 3. Pesticides Types of Pesticides: Chlorinated Hydrocarbons (CHCs): e.g., DDT, Endosulfan. Organophosphates, Metallic Salts, and Carbonates. Problems: Many pesticides are non-degradable, remaining in the environment for extended periods (persistent pollutants). Long-term Effects: Pesticide residues can contaminate water, harming both aquatic ecosystems and human health. 4. Waste from Livestock Sources: Poultry, Piggeries, and Slaughterhouses generate large amounts of waste. Impact: Chapter 6: Pollution and Conservation Methods 56  These wastes often reach water bodies through runoff, adding to the pollution burden by introducing organic matter, pathogens, and potentially harmful chemicals. Invasive Aquatic Species: Water Hyacinth 1. Water Hyacinth Overview Native Region: Amazon Basin Common Name: "Terror of Bengal" Type: Aquatic Weed 2. Ecological Impact Abundant Growth: Thrives in eutrophic (nutrient-rich) water bodies, where nutrient levels are excessively high due to pollution or fertilizer runoff. Imbalance in Ecosystem: Stagnation: Water Hyacinth creates dense mats on the surface of water, preventing the free flow of water and causing stagnation. Oxygen Depletion: These dense mats block sunlight, which reduces oxygen production by aquatic plants and algae. Oxygen Drain: As the plants decompose, they consume oxygen from the water, leading to hypoxia (low oxygen levels), which harms aquatic life, particularly fish. 3. Consequences Fish Stock Devastation: The depletion of oxygen and altered water conditions can lead to the destruction of fish populations and disrupt the aquatic food chain. Impact on Water Quality: Chapter 6: Pollution and Conservation Methods 57  The presence of Water Hyacinth can degrade the overall water quality, making it unsuitable for other forms of life, including humans. Pollution in River Ganga 1. Sources of Pollution Urban and Industrial Effluents: Major cities and industrial centers such as Haridwar, Kannauj, Kanpur, Allahabad, Varanasi, Patna, and Kolkata dispose of almost their entire wastewater and industrial effluents directly into the river. Key industries contributing to pollution include: Tanneries Sugar & Distillery Plants Pulp and Paper Mills 2. Types of Pollution Faecal Coliforms: The river is contaminated with faecal coliform bacteria along its entire length, posing serious health risks to those dependent on the river for drinking and other purposes. High Biochemical Oxygen Demand (BOD): The river water has high BOD, indicating the presence of excessive organic pollutants that consume oxygen, thereby depleting the oxygen needed by aquatic life. 3. Presence of Microplastics Types of Microplastics Found: The Ganga contains various types of microplastics, which are small plastic particles that pollute the water and harm aquatic ecosystems: Ethylene Vinyl Polyacetylene Chapter 6: Pollution and Conservation Methods 58  Polypropylene Polyamide (Nylon) Persistent Inorganic Pollutants (PIP) Environmental Impact: Microplastics, due to their non-biodegradable nature, persist in the river ecosystem, affecting water quality and posing a threat to both aquatic life and human health. Marine Pollution 1. Oil Spills Causes: The most common causes of oil spills include: Leakage during marine transport Leakage from underground storage tanks Offshore oil production accidents Impact: Oil Film: Oil is lighter than water and forms a thin film on the ocean surface. This film blocks oxygen from reaching floating plants and other producers, which affects the entire marine food web. Marine Life: Fish, shellfish, and plankton suffocate due to the lack of oxygen. The disruption leads to metabolic disorders and death within hours. Predators: Birds and sea mammals that feed on dead fish and plankton can also die due to poisoning from toxic oil residues. Cleaning Methods: Bregoli: A by-product of the paper industry resembling sawdust, used to absorb oil. Oil Zapper: A chemical or biological agent that helps in the removal of oil. Chapter 6: Pollution and Conservation Methods 59  Microorganisms: Some microbes can degrade oil, helping in natural cleanup. 2. Marine Plastic Pollution Economic Impact: The annual cost of marine plastic pollution is estimated at $13 billion in economic damage. By 2050, plastics are predicted to outweigh fish in the ocean by weight. Consequences: Impact on Photosynthetic Organisms: Marine plastic pollution interferes with the growth, photosynthesis, and oxygen production of Prochlorococcus, a significant photosynthetic cyanobacteria. This disturbance affects the entire marine ecosystem as it disrupts oxygen production and the base of the food chain. Eutrophication and Ageing of Lakes 1. Natural vs Cultural Eutrophication Natural Eutrophication: Gradual enrichment of water bodies with minerals and organic matter due to natural events over time. Cultural Eutrophication: Accelerated nutrient enrichment due to human activities (e.g., agricultural runoff, waste discharge). Leads to the ageing of lakes, causing a loss of biodiversity and ecosystem balance. 2. Lake Nutrient Classification Oligotrophic: Lakes with very low nutrients. Mesotrophic: Lakes with moderate nutrient levels. Eutrophic: Lakes with high nutrient levels, often leading to excessive plant growth and oxygen depletion. Chapter 6: Pollution and Conservation Methods 60  Most Lakes in India: Most lakes are either eutrophic or mesotrophic due to external nutrient influx and organic waste. 3. Effects of Eutrophication Collapsing Food Chains: Nutrient imbalances disrupt aquatic food webs. Invasive Species: New species invade ecosystems, causing ecological imbalance. Loss of Freshwater Lakes: Excess nutrients lead to the decline and destruction of lakes. Loss of Coral Reefs: Increased turbidity from nutrient overload harms coral reefs. Other Impacts: Poor navigation due to increased water turbidity. Colour changes (yellow, green, red) and foul smell. Increased biomass of inedible or toxic phytoplankton and algae. 4. Phytoplankton Role: Microscopic autotrophs at the base of aquatic food webs, critical for oxygen production and climate regulation. Types: Diatoms, dinoflagellates, cryptomonads, green algae, blue-green algae. Phytoplankton photosynthesize and some consume other organisms for additional energy. Contribution: Phytoplankton contribute to over 50% of the oxygen we breathe. Play a crucial role in absorbing CO2 and influencing climate. 5. Types of Chlorophyll Chlorophyll a, b: Found in higher plants, algae, cyanobacteria. Chapter 6: Pollution and Conservation Methods 61  Chlorophyll c: Found in diatoms, dinoflagellates, brown algae. Chlorophyll d: Found in red algae. 6. Eutrophication and Dead Zones Dead Zones: Areas with low dissolved oxygen (DO), harmful to most marine life. Size: Typically occur 200-800 meters below the surface in saltwater. Cause: Both natural processes (e.g., upwelling) and human activities (e.g., nutrient runoff) can create hypoxic zones. Indicator Species: Tubifex worms and insect larvae are tolerant of low oxygen and can survive in polluted waters. 7. Algal Blooms Description: Rapid growth of phytoplankton, which restricts sunlight penetration, leading to oxygen depletion. Types: Red/Brown Tides: Algal blooms with distinct colours due to specific types of phytoplankton. Blue Tide: Bioluminescent blooms caused by dinoflagellates. Impact: Algal blooms can lead to the death of aquatic plants, reduce oxygen levels, and disrupt marine life. Warm Water: High temperatures favor the occurrence of algal blooms. 8. Bioluminescence Definition: The ability of certain organisms to produce and emit light. Purpose: Acts as an antipredator mechanism. Organisms: Bioluminescence is common in deep-living and planktonic species. 9. Eutrophication Mitigation Chapter 6: Pollution and Conservation Methods 62  Phytoremediation: The use of plants (e.g., mangroves, wetland vegetation) to remove contaminants from soil and water. Phytoextraction: The process by which plants accumulate contaminants (heavy metals, toxins) in their roots and leaves. Example: Water Hyacinth can cleanse water by absorbing toxic materials and heavy metals. Water Pollution Control Measures: Bioremediation 1. Bioremediation Definition: The use of living organisms (microorganisms, plants) to remove or neutralize contaminants from soil or water. It can be enhanced through genetic engineering to design microorganisms specifically for bioremediation. 2. In-situ Bioremediation (Treatment at the site) Bioventing: Process: Nutrients are supplied through wells to contaminated soil, stimulating bacterial growth to degrade pollutants. Biosparging: Process: Air is injected under pressure below the water table to increase oxygen levels, enhancing biological degradation of contaminants by bacteria. Bioaugmentation: Process: Microorganisms are introduced to a contaminated site to boost the degradation of pollutants. Example: Oilzapper and Oilivorous-S: Developed by TERI ( The Energy And Resources Institute ) , this mixture of bacteria degrades oil pollutants in contaminated sites, leaving no harmful residues. Chapter 6: Pollution and Conservation Methods 63  3. Ex-situ Bioremediation (Treatment at a different location) Landfarming: Process: Contaminated soil is spread on a prepared bed and regularly tilled to aerate it, promoting microbial activity that breaks down organic pollutants. Bioreactors: Process: Contaminated solid materials or water are processed through engineered containment systems to treat the pollutants. Composting: Definition: The natural decomposition of organic materials into rich, fertile soil (compost). Example: Bacteria such as Bacillus flexus and Acinetobacter junii aid in arsenic detoxification during composting. Anaerobic vs. Aerobic Biodegradation 1. Anaerobic Biodegradation Pathogen Inactivation: More than 99% of pathogens are inactivated. Aeration: No aeration is required, as the process occurs in complete anaerobic conditions. Sludge Generation: Sludge generation is significantly less. Bacterial Inoculation: One-time bacterial inoculation is enough. Cost: Minimal maintenance and no recurring costs. Detergent Degradation: Anaerobes can degrade detergents. Energy Consumption: Forced aeration is not required, making it energy- efficient. 2. Aerobic Biodegradation Pathogen Inactivation: May result in incomplete pathogen inactivation if aeration is not sufficient. Aeration: Requires forced aeration, which is energy-intensive. Chapter 6: Pollution and Conservation Methods 64  Sludge Generation: Generates a large amount of sludge. Bacterial Inoculation: Requires repeated addition of bacteria/enzymes for continued efficiency. Cost: Maintenance and recurring costs are high due to energy requirements and ongoing bacterial addition. Detergent Degradation: Cannot tolerate detergents. Sewage Water Treatment for Domestic Use 1. Coagulation/Flocculation Purpose: To remove suspended solids. Process: Coagulants like ferric sulfate, sodium aluminate, or aluminium sulfate are added to untreated water, forming flocs that capture impurities. 2. Filtration