Module 5
Environmental pollution
→ Environmental Pollution refers to any addition of unwanted material in the
environment due to human activities that lead to undesirable changes in the
environment and ecology. For example, sewage water being released in clean
water sources like tanks, rivers, etc. is an example of water pollution.
Effects of Environmental Pollution
→ Pollution affects the very factors which support life on the ear, such as the air we
breathe, the water we drink and, at large, the ecosystems we depend upon. Thus, it
poses a threat to life on the earth.
→ Pollution poses one of the greatest challenges to the health of humans and other
living beings.
→ Though it affects the overall well-being of the entire society, vulnerable sections like
the poor, the children, the women etc are affected disproportionately by it.
→ Pollution has its negative impacts on the economy as well.
→ Other socio-economic impacts of pollution include food insecurity due to
decreased agricultural yield, forced migration due to water crisis etc.
Causes of Environmental Pollution
→ Rapid increase in human population has increased anthropogenic activities by
manifold. Most of these activities, in some way or the other, add some unwanted
things to the environment.
→ Rapid urbanization in recent times has led to increased construction activities. This,
in turn, is causing environmental pollution through different ways, such as release of
dust in air, generation of waste materials etc.
→ Increased population and urbanization have meant increased transportation
activities. This, in itself, is a major source of pollution.
→ An increased focus on industrialization of late is leading to rapid generation of
industrial wastes and emissions, and hence environmental pollution.
→ Some agricultural activities also lead to environmental pollution. For example,
excessive use of fertilizers and pesticides not only pollutes the soil but also nearby
water bodies due to spill over.
→ There are many other causes of environmental pollution, such as Burning of fossil
fuels, increased use of chemicals, etc.
Types of Pollution
Depending on the source as well as destination of the pollutants, there are various
types of pollution. Some major of them can be seen as follows:
Air Pollution
→ As per WHO, Air Pollution is contamination of the indoor or outdoor environment by
any chemical, physical or biological agent that modifies the natural characteristics
of the atmosphere.
→ According to WHO data, 99 percent of the world’s population breathes air that
contains high levels of pollutants and exceeds WHO guideline limits, with low and
middle-income countries experiencing the highest exposures.
Causes of Air Pollution
→ Industrial emissions, household emissions , motor vehicles emissions, forest fires
etc are some common sources of air pollution.
→ Pollutants of major public health concern include Particulate Matter, Carbon
Monoxide, Ozone, Nitrogen Dioxide, and Sulphur Dioxide.
Measures Taken to Control Air Pollution
→ The Air (Prevention & Control of Pollution) Act 1981
→ National Clean Air Programme (NCAP)
→ Continuous Ambient Air Quality Monitoring System (CAAQMS)
→ Green Crackers developed by CSIR-NEERI
→ The Great Green Wall of Aravalli
→ Some states like Delhi has built Smog Towers to tackle air pollution.
Water Pollution
Water pollution refers to release of unwanted substances into subsurface
groundwater or into water bodies like lakes, streams, rivers, estuaries, and oceans to a
level which negatively impacts the beneficial use of the water or natural functioning of
ecosystems.
→ Dissolved oxygen (DO) levels drop, Biological Oxygen Demand (BOD) rises,
aquatic species perish, eutrophication occurs, etc. as a result of water pollution.
Causes of Water Pollution
→ Agriculture is one of the primary sources of water pollution. Animal waste from
farms and livestock operations, pesticides, and fertilizers wash nutrients and
pathogens like bacteria and viruses into our waterways.
→ More than 80 percent of the world’s wastewater flows back into the environment
without being treated or reused, according to the United Nations.
→ Nearly half of the estimated 1 million tons of oil spills over into marine
environments.
→ Radioactive substances generated by uranium mining, nuclear power plants and
the hospitals that use radioactive materials for research and medicine. These waste
can persist in the environment for thousands of years, making disposal a major
challenge.
Measures Taken to Control Water Pollution
International Measures to Tackle Water Pollution
→ International Conventions to Mitigate Marine Pollution
→ Convention on Dumping Wastes at Sea or London Convention (1972)
→ The 1972 Convention on the Prevention of Marine Pollution by the Dumping of
Wastes and Other Matter, also known as “LC ’72” or the “London Convention,”
→ United Nations Convention on Law of the Sea (UNCLoS).
Measures Taken in India to Tackle Water Pollution
→ Water (Prevention and Control of Pollution) Act, 1974:
→ Initiatives to rejuvenate rivers, like Ganga Action Plan, Yamuna Action Plan etc.
→ Initiatives taken by the Central Pollution Control Board to tackle contamination and
over-exploitation of groundwater.
Noise Pollution
→ Noise Pollution is defined by the World Health Organization (WHO) as noise that
is louder than 65 decibels (dB).
→ Precisely speaking, noise becomes harmful above 75 dB and painful above 120 dB
Thus, it is advised to keep noise level below 65 dB during the day.
→ An ambient noise level advisable for the nighttime is 30 dBas restful sleep cannot be
achieved with noise levels above this.
Suggested Measures to Control Noise Pollution
→ Suppression of noise at the source
→ Acoustic zoning
→ Sound insulation at construction sites
→ Planting trees
→ Strict legislative measures.
Soil Pollution
→ The contamination of soil with abnormally high concentrations of toxic
substances is referred to as soil pollution.
→ Given the numerous health risks it contains, it is a serious environmental concern.
For instance, exposure to soil with high Benzene concentrations increases the
risk of developing Leukaemia.
Causes of Soil Pollution
→ Phenomena such as loss of organic carbon, erosion, increased salt content,
acidification, compacting, and chemical pollution are the major causes of current
soil degradation.
Suggested Measures to Tackle Soil Pollution
→ Promote eco-friendly practices in business, agriculture, and stock breeding and
other sectors of the economy.
→ Ensure an efficient transportation and treatment of wastewater through proper
urban planning.
→ Increase topsoil conservation, landscape restoration,
→ Mining waste management.
Nuclear Hazards
Increasing frequency of extreme weather events is likely
to increase the risk of nuclear disasters.
Regardless of whether the accident is an isolated event or
a large-scale catastrophe, radiation emergencies can
greatly impact health, property and the environment.
Radiation emergencies include:
→ nuclear emergencies, such as the explosion of a nuclear weapon
→ dirty bombs
→ radiological exposure devices
→ nuclear power plant accidents
→ transportation accidents involving radiation
→ occupational accidents, such as over-exposure to radiation in health-care facilities.
