Pollution and its Impact on Life
GS 3, Environment and Pollution.
Context:
- In 2016, India recorded the second-highest number of deaths attributed to ambient air pollution, with over 10.8 lakh deaths.
- According to the 1986 Environmental Protection Act (EPA), “Environmental Pollution” is the presence of a pollutant.
Pollutants:
- Pollutants are defined as any solid, liquid, or gaseous material existing in a concentration that is or may be harmful to the environment.
- Pollutants are the agents that produce environmental contamination. Pollutants are physical, chemical, or biological substances that are introduced into the environment deliberately or inadvertently that are directly or indirectly hazardous to people and other living species.
Air Pollution:
- Air pollution is defined as the presence of any solid, liquid, or gaseous substance, including noise and radioactive radiation, in such concentrations in the atmosphere that it is directly or indirectly harmful to humans or other living organisms, plants, or property, or interferes with normal environmental processes.
Air contaminants are divided into three categories:
- Natural Pollutants: These are pollutants that arise from natural causes such as forest fires caused by lightning, pollen distribution, soil erosion, volcanic eruptions, volatile organic compounds from leaves and trees, organic matter decomposition, and natural radioactivity, among others.
- Primary Pollutants: A primary pollutant is a hazardous material that enters the air directly as a result of human activity. When coal, oil, natural gas, or wood is burned, carbon dioxide and carbon monoxide are produced, with cars generating a significant amount of carbon monoxide. All of these gases are released into the environment. Another significant pollutant is sulphur dioxide (SO2), which is released into the environment when coal and oil with sulphur as a contaminant are burned in power plants. Nitrogen oxides, hydrocarbons, and suspended particulate matter are examples of main pollutants.
- Secondary pollutants are caused by a detrimental chemical interaction between two or more air components. Sulphur dioxide, for example, the principal pollutant, interacts with oxygen in the atmosphere to generate sulphur trioxide (SO3) (2SO2 + O2 = 2S03). Sulphur trioxide can then react with airborne water vapour to generate droplets of sulphuric acid (H2SO4), a secondary pollutant. Another secondary contaminant is tropospheric ozone (O3).
Air Pollution Sources-
- Point Sources: Industries, power plants, garbage burning, and so on are examples of.
- Areal Sources: Heating and cooling operations, crop residue burning, forest fires, and so on.
- Line Sources: Traffic, aircraft, etc.
Air contaminants are classified into two groups based on their state:
- Gaseous Pollutants such as Carbon Dioxide (CO2), Nitrogen Oxides such as NOx (N2O, NO2).
- Suspended Particulate Matter (SPM).
Particulate Pollutants:
- Suspended Particulate Matter (SPM) refers to dust, liquids, and soot suspended in the air. Based on size, it is classified as dust, fume, mist, smoke, and aerosols. Vehicles, power plants, building operations, oil refineries, railway yards, market places, factories, and so on are major sources of SPM (suspended particulate matter).
- Particles less than 10m (such as PM10 and PM2.5) are referred to as Respire-able Suspended Particulate Matter (RSPM). They float in the air stream and move freely.
Aerosols:
- Aerosols are tiny particles floating in the air. They are smaller than 1 micron in size. Persistent aerosols are formed by particles less than 0.02m in size. The aerosols are continually influenced by the earth’s gravitational attraction.
There are two types of aerosols in the atmosphere:
-Natural, and
-Man-made.
Natural aerosols include fog, bacteria, plant spores, pollen, and so on. These typically do not pollute the atmosphere.
The second category of aerosols, which include cement powder, flue dust from coal dust combustion, quartz and asbestos powder, oil smokes, tobacco smokes, and radioactive aerosols, are air pollutants caused mostly by human activity and pose a persistent threat to the environment.
Black Carbon (BC), or Carbon Black or Elemental Carbon (EC):
- It is one of the most important light-absorbing aerosols in the atmosphere and is commonly referred to as soot. It is formed of pure carbon clusters and skeletal balls. The contribution of Black Carbons from fossil fuels, as projected by the IPCC in its Fourth Assessment Report, is a worldwide mean radiative forcing.
Hydrocarbons:
- Hydrocarbons are carbon and hydrogen compounds. Some hydrocarbons are carcinogenic in nature and have a direct effect on humans. They are formed during the manufacturing of coke and the smouldering of garbage piles near coal mines, as well as during inappropriate coal burning.
Fly Ash:
- Fly ash is emitted primarily by thermal power plants as a by-product of coal combustion activities. Fly ash pollutes the air and water, and it may create heavy metal contamination in bodies of water. It is made up of silica, iron oxides, and other heavy metals. Fly ash impacts plants either directly through deposition on leaf surfaces or indirectly through deposition on soil. Fly ash is currently utilised to make bricks as well as a waste material.
Impact of Pollution:
Concerning Human Beings-
- Breathing polluted air increases the chances of developing asthma and other respiratory disorders.
- If healthy persons were exposed to ground ozone for 6 to 7 hours, their lung function may reduce and develop Respiratory Inflammation.
- The majority of air pollutants are carcinogens, and living in a polluted region puts individuals at risk of cancer.
- Coughing and wheeze are typical complaints among city dwellers.
- It affects the immunological, endocrine, and reproductive systems.
- High levels of particle pollution have been linked to an increase in the occurrence of cardiac diseases.
Concerning Plants-
- Plants are negatively affected by photochemical haze. When exposed to sunlight, different contaminants react to generate ground ozone and per-oxy-acetyl nitrate (PAN).
- Plants are severely harmed by ozone. It enters the leaves through the stomata, which are employed for regular gas exchange, and changes the permeability of the stomatal membranes. This creates nutritional and electrolyte imbalances, which leads to cell death.
- In consequence, ozone accelerates leaf respiration, killing the plant by depleting its food supply. Chronic ozone exposure may weaken plants and make them more prone to disease, or it may prematurely age plants, lowering food output without causing visible damage.
- PAN is the other component of photochemical smog which is Phyto-toxic. It inhibits photosynthesis, harming the plant by preventing food production.
- Sulphur dioxide has the potential to cause catastrophic plant damage by contributing to acid rain. As previously stated, these rains deplete nutrients from the soil and plants and have an impact on soil organisms responsible for nitrogen fixation.
- Acids increase the absorption of harmful heavy metals from soil by plants.
Control of Air Pollution:
Industrial Pollution Control-
- Filters, electrostatic precipitators, inertial collectors, scrubbers, gravel bed filters, and dry scrubbers are used to manage industrial pollution, particularly particulate matter.
- Filters are used to remove particulate debris from a gas stream.
- Electrostatic precipitators (ESP) charge the issuing dust with ions, and the ionised particulate matter collects on an oppositely charged surface. The particles are cleared from the collection surface by shaking or tapping it on occasion. ESPs are utilised in boilers, furnaces, and a variety of other units in thermal power plants, cement plants, steel plants, and so on.
- Inertial Collectors: It operates on the idea that the inertia of SPM in a gas is greater than that of its solvent, and because inertia is proportional to particle mass, this device collects heavier particles more effectively. A ‘Cyclone’ is a type of inertial collector that is commonly employed in gas cleaning operations.
- Scrubbers: Scrubbers are wet gatherers. They remove aerosols from a gas stream by either collecting wet particles on a surface and then removing them, or by wetting the particles with a cleaning liquid. Particles become caught as they pass across the interface from the supporting gaseous medium to the liquid cleaning media.
- Removal of Gaseous Pollutants: Gaseous pollutants can be removed by absorption in a liquid using a wet scrubber. Depending on the kind of gas to be removed, an alkaline solution is required since it dissolves sulphur dioxide.
- Gaseous contaminants can be absorbed by activated solid surfaces such as silica gel, alumina, carbon, and so on. Water vapour can be removed using silica gel.
- Condensation enables the recovery of various by-products from liquid effluents in the coal and petroleum processing sectors.
Pollution Control in Vehicles:
- Use of Quality Fuel: BS-IV was accepted across the country in 2017, and the government has decided to implement BS-VI criteria by 2020, bypassing BS-V.
- Alternative Fuels: Increased promotion and usage of alternative fuels such as CNG/LPG, electric cars, hybrid and battery-powered E-rickshaws, and buses.
- Vehicles with Zero Emissions: Alternative modes of transportation such as cycle rickshaws, bicycles, and walking should be encouraged.
- Mass Transit System (MTS): The Mass Transit System (MTS) should be encouraged. Metro, bus, rapid transit, and urban rail should be implemented in major cities. It lessens reliance on private automobiles.
- Projects for Urban Roads and Flyovers: Dedicated bus lanes minimise congestion and hence emissions.
- Tree cover or green cover like installing Plants, can absorb carbon dioxide and other pollutants.
Govt Initiatives and Schemes to curb Air Pollution:
Initiative for National Biomass Cook Stoves (NBCI):
The National Biomass Cook Stoves Initiative (NBCI) was established on December 2, 2009, in New Delhi, with the primary goal of increasing the usage of better biomass cook stoves. As a follow-up to the National Biomass Cookstove Initiative (NBCI), the Ministry launched a new proposal during the 12th Plan Period to promote the development and deployment of Unnat Chulhas (Biomass Cookstoves) across the country.
Lightening a Billion Lives:
Lighting a Billion Lives is a global programme led by TERI (The Energy and Resources Institute, Delhi) to improve clean energy availability and provide last-mile energy services for both basic and productive usage. The effort helps energy-insecure communities move from inefficient traditional energy sources to contemporary, more efficient, and sustainable energy options.
The interventions concentrated their efforts on achieving three primary goals:
- To replace inefficient and dangerous lighting and cooking practises with clean energy alternatives that are efficient, economical, and dependable.
- To enable the productive use of clean energy for improved education, health, and livelihood possibilities, so empowering the poor to break free from poverty.
- Access and adoption of demand responsive solutions at the last mile will be facilitated through capacity building and enterprise growth.
Pradhan Mantri Ujjwala Yojana (PMUY):
The Ministry of Petroleum and Natural Gas introduced the Pradhan Mantri Ujjwala Yojana. This initiative would give BPL families with LPG connections at a cost of ‘1600 per connection.
- It seeks to protect women’s and children’s health by supplying them with a clean cooking fuel – LPG – so they don’t have to risk their health in smoky kitchens or walk into dangerous places gathering firewood.
- The connections would be granted in the name of the women of the families, ensuring women’s empowerment, particularly in rural India. The BPL families would be identified using Socio Economic Caste Census Data.
National Air Quality Monitoring Program (NAMP):
- The Central Pollution Control Board is implementing the National Air Quality Monitoring Programme, a countrywide initiative for monitoring ambient air quality (NAMP). The network includes of 683 operational stations spanning 300 cities/towns across the states and Union Territories.
