Pollution
- Pollution occurs when an amount of any substance or any form of energy is put into the environment faster than it can be dispersed or safely stored. The term pollution can refer to both artificial and natural materials that are created, consumed, and discarded in an unsustainable way.
- Pollution can be caused by human activities such as manufacturing, agriculture, transportation, and poor waste management. It can also be caused by natural events such as forest fires and volcanoes.
The major types of pollution, usually classified by environment, are:
- Air pollution
- Water pollution
- Soil pollution
- Noise pollution
- Light pollution
- Plastic pollution
- Thermal pollution
- Radioactive pollution
All types of pollution can have negative effects on the environment and wildlife and often affect human health and well-being.
Many large cities have harmful levels of air pollution, where particles and gases from transportation, heating, and manufacturing accumulate. The problem of plastic pollution on land and in the oceans has only grown as the use of single-use plastics has increased worldwide. In addition, greenhouse gas emissions, such as methane and carbon dioxide, continue to drive global warming and pose a major threat to biodiversity and public health.
Air Pollution
Air pollution is the release into the atmosphere of various gases, finely divided solids, or finely dispersed liquid aerosols at a rate greater than the environment’s natural capacity to dissipate and dilute or absorb them. These substances can reach concentrations in the air that cause undesirable health, economic, or aesthetic effects.
Gaseous criteria air pollutants of primary concern in urban settings include sulfur dioxide, nitrogen dioxide, and carbon monoxide; these are emitted directly into the air from fossil fuels such as fuel oil, gasoline, and natural gas that are burned in power plants, automobiles, and other combustion sources. Ozone (a major component of smog) is also a gaseous pollutant; it is formed in the atmosphere through complex chemical reactions that occur between nitrogen dioxide and various volatile organic compounds.
Airborne suspensions of extremely small solid or liquid particles called “particulates” (soot, dust, smoke, smog, haze), typically less than 10 micrometers (one-millionth of a meter) in size, are important air pollutants because of their very harmful effects on human health. They are emitted by a variety of industrial processes, coal or oil-burning power plants, residential heating systems, and automobiles. Lead smoke (particles less than 0.5 microns in size in air) is particularly toxic and is a significant pollutant of many diesel fuels.
The criteria pollutants are emitted in industrialized countries at very high rates, usually measured in millions of tons per year. All except ozone are released directly into the atmosphere from a variety of sources. They are regulated primarily by establishing ambient air quality standards, which are maximum allowable concentrations of each criteria pollutant in the atmosphere.
Very small pieces of solids or liquid droplets suspended in the air are called particles. Except for airborne lead, which is treated as a separate category, they are characterized by size and phase (solid or liquid) rather than chemical composition. For example, solid particles between about 1 and 100 microns in diameter are called dust particles, while airborne solid particles less than 1 micron in diameter are called smoke.
The particles of most concern with regard to their effects on human health are solids less than 10 microns in diameter, because they can be inhaled deep into the lungs and become trapped in the lower respiratory system. Some particles, such as asbestos fibers, are known carcinogens (cancer-causing agents) and many carbonaceous particles are. Major sources of particle emissions include fossil-fuel power plants, manufacturing processes, fossil-fuel residential heating systems, and gasoline-powered vehicles.
Water Pollution
Water pollution occurs when harmful substances—often chemicals or microorganisms—contaminate a river, lake, ocean, aquifer or other body of water. Toxins from farms, towns and factories easily dissolve in it, degrading the quality of water and making it toxic to humans or the environment. This causes water pollution.
Domestic sewage is the primary source of pathogens (disease-causing microorganisms) and resistant organic matter. Since pathogens are excreted in feces, all sewage discharged from cities and towns is likely to contain some type of pathogen, potentially posing a direct threat to public health. Degradable organic matter presents a different type of threat to water quality. As organics in sewage are naturally decomposed by bacteria and other microorganisms, the dissolved oxygen content of the water is depleted.
Domestic sewage is also a major source of plant nutrients, mainly nitrates and phosphates. Excess nitrates and phosphates in the water promote the growth of algae, which sometimes causes abnormally dense and rapid growths known as algae blooms. When the algae die, dissolved oxygen in the water is reduced as microorganisms use oxygen to digest the algae during the process of decomposition.
Oil spills occur when oil from roads and parking lots is carried into water bodies. The cost of oil spills is substantial, both economically and ecologically. Oil on ocean surfaces is harmful to many forms of aquatic life because it prevents enough sunlight from penetrating the surface, and it also reduces dissolved oxygen levels.
BOD stands for Biochemical Oxygen Demand, which is a chemical test that measures the amount of oxygen needed to break down organic matter in the water. BOD is a key indicator of water quality and pollution. Higher BOD means there is more organic matter present in the water, which depletes oxygen more rapidly. This can cause aquatic organisms to suffocate and die. Wastewater treatment plants use BOD to measure the efficiency of their BOD removal and to control plant processes. The goal is to reduce the BOD of wastewater before it is released into a water body.
Soil Pollution
Soil can get polluted in various ways. For example, frequent use of pesticides is a significant issue as it reduces soil biodiversity and resilience, and can lead to contamination of food and fodder. Excess nutrients are another source of soil pollution. They lead to ecosystem eutrophication and reduce biodiversity, and result from the use of fertilizers and manures or the deposition of certain air pollutants.
Soil pollution has an adverse effect on food security in two ways-Soil pollution can reduce crop yields; this is because toxic pollutants spoil the soil for a long time, and crops grown in polluted soil are unsafe for consumption by animals and humans.
Wastes such as paper, plastic, metals, glass, organic matter, petroleum products and industrial wastes, etc. should be recycled and reused to reduce soil pollution. Example: Industrial wastes should be properly treated at the source itself. Integrated wastewater treatment methods should be adopted.
Noise Pollution
Noise pollution, unwanted or excessive sound that can have harmful effects on human health, wildlife and environmental quality. Noise pollution is usually generated inside many industrial facilities and some other workplaces, but it also comes from highway, railway and air traffic and outdoor construction activities.
According to the Central Pollution Control Board (CPCB), the permissible noise levels in India are as follows:
Industrial areas: 75 decibels (dB) during the day and 70 dB at night
Commercial areas: 65 decibels during the day and 55 decibels at night
Residential areas: 55 decibels during the day and 45 decibels at night
Silent zones: 50 decibels during the day and 40 decibels at night
Light Pollution
Light pollution, unwanted or excessive artificial light. Like noise pollution, light pollution is a form of waste energy that can cause adverse effects and reduce environmental quality. Also, because light (transmitted as electromagnetic waves) is usually produced by electricity, which is usually produced by the combustion of fossil fuels, light pollution is the use of too much, inappropriate or poorly designed artificial light, which can negatively affect the environment, wildlife and human health.
Light pollution can have many negative consequences, including –
Health: Disrupted circadian rhythms and sleep deprivation can lead to health concerns such as obesity, type II diabetes and heart disease.
Wildlife: Light pollution can harm wildlife, such as migratory birds and coastal birds that are killed by artificial light at night. It can also disrupt the development of coral larvae.
Aquatic Ecosystems: Light pollution can increase the risk of harmful algae blooms.
Night Sky: Light pollution obscures the view of the natural night sky.
To reduce light pollution, use light only when needed. Use warm-white, yellow or amber lighting to aid night vision.
Use shielding to prevent light from spreading more than necessary.
Turn off lights after use, or use timers and motion detectors.
Encourage neighbors to reduce their light pollution.
Light pollution is the presence of any unwanted, inappropriate or excessive artificial light.
The term light pollution refers to the effects of any poorly implemented light sources during the day or night. Light pollution can be understood not only as a phenomenon resulting from a specific source or type of pollution, but also as a contributor to the broader, collective effect of various sources of pollution.
Light pollution is caused by the inefficient or unnecessary use of artificial light. Specific categories of light pollution include light trespass, over-illumination, glare, light clutter and sky glow.
Plastic Pollution
Plastic pollution is a global problem. Every year 19-23 million tons of plastic waste leak into aquatic ecosystems, polluting lakes, rivers, and seas.
Plastic pollution can alter habitats and natural processes, reducing the ability of ecosystems to adapt to climate change, directly affecting the livelihoods, food production capabilities, and social well-being of millions of people.
Plastic pollution, the accumulation in the environment of synthetic plastic products to such an extent that they cause problems for wildlife and their habitat as well as human populations.
Plastic was found as a persistent pollutant of many environmental locations from Mount Everest to the bottom of the ocean. Whether being mistaken for food by animals, flooding low-lying areas by blocking drainage systems, or simply causing significant aesthetic ailments, plastic has gained attention as a massive pollutant.
The ocean is downstream from almost every terrestrial location, it is the receiving body for most of the plastic waste generated on land. Several million tons of debris end up in the world’s oceans every year, and the vast majority of it is improperly discarded plastic waste.
Plastic is a synthetic, organic polymer made from fossil fuels such as gas and petroleum. According to the United Nations Environment Programme, more than 460 million metric tons of plastic are produced each year. Plastic is used in nearly all consumer and industrial activities, from construction and vehicles to electronics and agriculture.
Improperly discarded plastic waste pollutes and damages the environment, becoming a widespread driver of biodiversity loss and ecosystem degradation. It threatens human health, impacts food and water security, burdens economic activity, and contributes to climate change.
In 2024, 220 million tonnes of plastic waste will be generated, of which 70 million tonnes will go into nature. This is due to the imbalance between the amount of plastic consumed and the ability to manage it.
The sources of pollution are mainly land-based, coming from urban and stormwater runoff, litter, industrial activities, tyre abrasion, construction and agriculture. In the marine environment, plastic pollution originates mainly from land runoff, but also includes paint sheds from shipping, fishing equipment and more.
Due to solar radiation, wind, currents and other natural factors, plastic breaks down into microplastic (smaller than 5 mm) and nanoplastic (smaller than 100 nm) particles. ‘Primary’ microplastic particles are also shed by products such as synthetic textiles and tyres through abrasion. Nanoplastics are able to cross cell membrane walls and enter living organisms.
Reducing pollution from plastics will require action and international cooperation to reduce plastic production, including innovation, better product design and efforts to develop environmentally friendly alternatives, as well as improving waste management and increasing recycling.
An uncommon form of thermal pollution involves the release of cold or chilled water from storage reservoirs into warmer water, lowering the temperature of the receiving water bodies.
Thermal Pollution
It is caused by hot wastes and warm water bodies. Warm water has low oxygen content. Hence the rate of decomposition of organic matter is reduced. Green algae are replaced by less desirable blue green algae.
Thermal pollution is the increase or decrease in the temperature of a natural body of water due to human influence. A common cause of thermal pollution is the use of water as a coolant by power plants and industrial manufacturers. When water used as a coolant is returned to the natural environment at a higher temperature, the change in temperature affects organisms by (a) decreasing oxygen supply, and (b) affecting ecosystem structure.
Increase in the temperature of the environmental system
Thermal pollution is caused by uncontrolled human activities such as (1) poor agricultural practices leading to thermal pollution, (2) removal of vegetation along the river banks, (3) soil erosion due to construction activities, (4) excessive cutting of tall vegetation and trees, and (5) setting up of power generation units and huge industrial units, using cold water and discharging hot water as steam.
The following major sources are the main contributors of thermal pollution, which include (1) hydroelectric power plants, (2) domestic sewage systems, (3) industrial waste, (4) coal-fired power plants, and (5) nuclear power plants.
Thermal pollution of air and water usually occurs with the use of geothermal fields. Excess heat emitted as steam can affect the formation of clouds and change the weather locally. Discharge of hot water into rivers, streams, lakes, and ponds can harm the aquatic ecosystem.
Water pollution and thermal pollution can be reduced through wastewater treatment, careful storage of wastewater in ponds, and re-injection into deep wells, which are considered the most effective ways to combat water pollution.
Thermal pollution refers to the increase in the temperature of natural water bodies such as rivers, lakes, and oceans as a result of human activities. This form of pollution is caused by the discharge of hot water from power plants, industrial facilities, and other sources. The increase in temperature can have harmful effects on the environment, including aquatic life and the surrounding ecosystem. In this article, we will explore thermal pollution in detail, including its causes, effects, and possible solutions.
The primary cause of thermal pollution is the discharge of hot water into natural water bodies. This hot water is typically generated by industrial processes such as power generation, chemical manufacturing, and paper production. Power plants, in particular, are major sources of thermal pollution because they use water to cool their systems before releasing it back into the environment. Another cause of thermal pollution is deforestation, which can lead to a loss of shade over streams and rivers, resulting in higher water temperatures. Additionally, urbanization can also contribute to thermal pollution as asphalt and concrete surfaces absorb and retain heat, warming the water downstream.
Thermal pollution can have a significant impact on aquatic ecosystems. Many aquatic organisms, such as fish, insects, and amphibians, are adapted to specific temperature ranges. A sudden increase in water temperature can stress or even kill these organisms. For example, salmon are particularly sensitive to changes in water temperature and are known to perish in large numbers when exposed to high temperatures. Thermal pollution can also disrupt the food chain in aquatic ecosystems. As water temperatures increase, the metabolism of algae and other primary producers speeds up, increasing their growth rate. However, this can also lead to a decrease in dissolved oxygen levels as algae consume more oxygen during respiration. As a result, fish and other aquatic animals that require oxygen to survive may be deprived of this vital resource, leading to deaths and disruptions in the food web. Thermal pollution can also affect water quality by promoting the growth of harmful bacteria and other pathogens. Warmer water provides an ideal environment for the growth of many types of bacteria, including those that cause diseases such as cholera, typhoid fever, and dysentery.
One potential solution to thermal pollution is the use of cooling towers. Cooling towers are large structures that use evaporation to cool water before it is released back into the environment. Using this method, the temperature of the water can be reduced before it enters a natural water body, reducing the effects of thermal pollution. Another solution is the implementation of strict regulations on industries that discharge heated water into natural water bodies. Regulations may require industries to monitor the temperature of their discharges and limit the amount of heated water they release. Additionally, regulations can encourage the use of alternative cooling methods, such as air cooling or closed-loop systems.
Reducing the effects of deforestation and urbanization can also help reduce thermal pollution. Planting trees along riverbanks and other areas near water bodies can provide shade, which can help keep water temperatures lower. Additionally, the use of green infrastructure in urban areas, such as green roofs and rain gardens, can help reduce runoff water and prevent heat absorption by concrete and asphalt surfaces. Thermal pollution is a significant environmental issue that can have a profound impact on aquatic ecosystems. The discharge of hot water from industries and power plants can increase water temperatures, which can stress or kill aquatic organisms and disrupt the food chain. However, by implementing solutions such as cooling towers, strict regulations, and green infrastructure, we can work to reduce the effects of thermal pollution and protect our water bodies and the ecosystems they support.
Radioactive Pollution
Radioactive pollution is the result of radionuclides being released into the environment. A radionuclide is an atom with an unstable nucleus that has excessive energy.
Radioactive contamination can enter the human body through ingestion, breathing, absorption or injection. Long-term exposure to radiation, at doses lower than those that cause severe radiation sickness, can damage DNA leading to cancer or birth defects. High levels of exposure can cause radiation sickness with symptoms that vary depending on exposure levels from a decrease in blood cells to almost immediate death. Marine organisms can also be affected and reproductive stages and growing tissues are the most sensitive in marine fish. Mammals appear to be the most sensitive of all organisms, followed by birds and then insects.
Radioactive pollution, also known as radioactive contamination, is the release of radioactive substances into the environment. This may include land, water, air or living organisms. The radioactive substances then release ionizing radiation, which can contaminate the surrounding environment.
Radioactive pollution can have many effects, including:
Health effects: Radioactive pollution can cause illness or death in humans, animals, and plants. It can also cause genetic mutations in living organisms and their offspring.
Environmental effects: Radioactive pollution can make soil barren and unsuitable for crops for decades. It can also make the air dangerous to breathe.
Burns: Radioactive pollution can cause burns, red sores, and wounds on the body.
Radioactive pollution can occur from many sources, including: nuclear explosions and nuclear weapons testing, production and dismantling of nuclear weapons, mining of radioactive minerals, management and disposal of radioactive waste, and accidents at nuclear power plants.
Radioactive pollutants are one of the most dangerous and emerging classes of pollutants. Radioactive pollution is one of the most dangerous anthropogenic activities in nature. Unlike other pollutants, there is no treatment technique for radioactive pollution, and it can be termed as irreversible damage to the environment (Kennish, 1996). Radioactive pollutants are released into the environment in various forms, but the most common way can be disposal of contaminated water into the aquatic ecosystem. Other possible ways of radioactive contamination include disposal of radioactive elements or the stuffing of nuclear submarines due to mechanical failures.
There have been two major sources of radioactive pollution: Anthropological activities of synthesis of radioactive compounds. On the other hand, nature also produces radioactive compounds, which generally pollute continental waters. Natural radioactive compounds are generally synthesized from the weathering of rocks and the disintegration of their primordial nuclei. The type and concentration of the synthesized compound depends on the available substratum and the aggressiveness of the water.
Pollution Affects Life on Earth Pollution can have serious negative effects on the environment and the lives of humans and animals.
Pollution can have serious consequences
Pollution can cause long-term consequences such as loss of biodiversity, loss of vegetation, and the presence of harmful chemicals in the atmosphere and food.
Pollution can cause health hazards Air pollution can cause respiratory diseases and other health hazards.
Air pollution can reduce visibility, block sunlight, cause acid rain, and harm forests, wildlife, and agriculture.
Pollution can cause climate change:
Greenhouse gas pollution causes climate change, which affects the entire planet.
Pollution increases natural disasters Carbon pollution can cause natural disasters such as earthquakes and cyclones.
We can take action to reduce pollution by adopting green lifestyles, such as using energy-efficient lighting, using climate-friendly autos, and using wind and solar power.
