# UPSC Ecology And Environment Environmental Issue And Environmental Pollution Notes - Environmental Issues

Notes - Environmental Issues

Category : UPSC

Environmental Issue

Introduction

Environmental issues are harmful effects of human activity on the biophysical environment. Environmentalism, a social and environmental movement, addresses environmental issues through advocacy, education and activism.

Our environment is constantly changing, which no one can deny. With these great environment changes, it becomes highly important for us to become increasingly aware of the environmental problems as well. With a monumental inundation of natural disasters, warming and cooling periods, different types of weather forms and much more, people should be aware of what types of environmental problems our earth is facing.

Our planet is on the verge of a severe environmental crisis. Current environmental problems make us susceptible to disasters and tragedies, now as well as in the future. We are in a phase of planetary emergency, with environmental problems blooming around us. Unless we address the various issues proactively and sincerely we are surely going to be wrecked with this disasters. All the current environmental problems need an urgent attention.

Different Environmental Issues and Its Effect On Climate

Environmental issues are increasing day by day and it has an adverse effect on climate. Some of the Environmental issues are discussed below:

Global Warming

Atmostpheric gases like carbondioxide

$(C{{O}_{2}})$

, nitrogen oxide

$(N{{O}_{2}})$

methane

$(C{{H}_{4}})$

, chlorofluro carbons (CFCs) and water vapour have the ability of trapping the outgoing radiation (infrared) from the surface of earth. Such trapped radiation by the earth's surface cannot pass through these gases present in the atmosphere and exhibits the thermal energy or heat in the atmosphere. As a result the temperature of atmosphere is on rise globally. The phenomenon of increase of temperature i.e. heating in green houses are known as greenhouse effect. The increase in the temperature of earth's surface is known as global warming. Global warming leads to rising temperatures of the oceans and the earth's surface causing melting of polar ice caps, rise in sea levels and also unnatural patterns of precipitation such as flash floods, excessive snow desertification.

Elects of Global Warming

The Intergovernmental Panel on Climate Change (IPCC) was established in 1988 by the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP) in recognition of the problem of global warming. IPCC has estimated the following effects of global warming:

• Earth's temperature will rise by

$1-30{}^\circ C$

• in next few decades, leading to extreme weather changes (heat waves, hurricanes and severe winters), changes in ocean currents and marine life. The largest glacier chain in the tropics is melting fast because of rising temperatures and peaks are turning brown. This trend is endangering future water Glaciers serve agriculture, hydel plants and feed rivers that supply water to the sprawling cities and shanty towns on Peru's bone-dry Pacific coast. Quelccaya, in southern Peru, the world's largest tropical ice-cap, is retreating at about 200 feet per year, up from 20 feet per year in the 1960s. Lonnie Thompson, a leading glacier expert of Ohio State University, monitoring glacier retreat on the Andes, Himalayas and Kilimanjaro, said that the rate of ice loss in glaciers all over the world is actually accelerating.
• If $C{{O}_{2}}$ concentration doubles, Earth's temperature may rise by$50{}^\circ C$. Coastal areas will see a rise in water levels by 0.5 – 5.0 feet due to melting of mountain glaciers, polar ice-caps, etc.
• Islands like Maldives would get submerged. In 1999, two uninhabited islands in the South Pacific (Tebua Tarawa and Abanuea) were submerged by rising sea levels, and two neighboring inhabited islands (Kiribati and Tuvalu) are on the brink of submersion as well.
• The biggest glacier in the Peruvian Andes was retreating by 5 meters per year some 20 years ago; today it is shrinking by 33 meters per year. The second largest glacier on Earth, the Greenland ice sheet, is thinning at an unprecedented rate of one meter each year.
• The Arctic Sea ice has thinned by 40% in the last two decades, while Mount Everest is losing height at the rate of 1.5 meters per year.

As global warming's, terrifying threat increases, our planet's nations come together at the panes climate conference (2015) to fight for our future.

In the wake of the paries conference America must lead the fight against global warming. We need to embrace clean energy and leave our dirt fossil fuels in the ground.

Here are five key steps the U.S. leaders should take to protect our planet.

(i) Suppost a just, ambitions and binding international climate treaty:

Under the parts framework and beyond, the U.S. should back efforts to end fossil fuel use in developed nations by 2050.

(ii) Strengthen the clean power plan:

The U.S. needs to move rapidly away from all fossil fuels and toward wildlife-friendly sources of clean energy.

(iii) Cut pollution from airplanes and other unregulated sources:

The Environmental protection Agency acknowledges that airoplane pollution endangers our climate.

(iv) Halt new fossil fuel development in America's oceans and on our public lands:

Ending new fossil fuel leasing on public lands and offshore areas controlled by the U.S. would keep up to 450 billion tons of greenhouse gases from polluting the atmosphere, according, to a recent analysis prepared for the centre by scientists at Ecoshift.

(v) Crack down on fossil fuel exports and transport

We must halt the dangerous push to send America's dirty fossil fuels abroad.

Control of Global Warming

• Cutting down the use of fossil fuel
• Improving efficiency of energy fuel
• Reducing deforestation
• Planting the trees
• Slowing down the growth of human population
• Reduction in the emission of green- house - gases into the atmosphere.

Green House Effect

The earth gets energy from the sun in the form of sunlight. The earth's surface absorbs some of this energy and heats up. That's why the surface of a road can feel hot even after the sun has gone down because it has absorbed a lot of energy from the sun. The earth cools down by giving off a different form of energy, called infrared radiation. But before all this radiation can escape to outer space, greenhouse gases in the atmosphere absorb some of it, which makes the atmosphere warmer. As the atmosphere gets warmer, it makes the earth's surface warmer, too. Without this Greenhouse effect the earth would be at least 30 degrees cooler, in which life would not exist.

Greenhouse Gases

A greenhouse gas (GHG) is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range. This process is the fundamental cause of the greenhouse effect. The primary greenhouse gases in Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, ozone, and chlorofluorocarbons.

• Water vapour contributes to 36 – 72% of Greenhouse
• Carbon Dioxide $(C{{O}_{2}})$ arises from burning fossil fuels and as a result of deforestation. It contributes to 9 – 26% of Greenhouse effect. It is the primary greenhouse gas emitted through human activities.
• Methane$(C{{H}_{4}})$, also called "Marsh gas", arises from rice paddies, wetlands, enteric fermentation in cattle, burning of wood, and landfills. It is responsible for about 4 – 9% of Greenhouse effect.
• Nitrous Oxide $(N{{O}_{2}})$ contributes (5%) which arises from coal burning, biomass burning, and breakdown of chemical fertilizers.
• Chlorofluorocarbons (CFCs) and their replacements (15%) are 1000 times more heat absorbent than carbon They reach the atmosphere from refrigeration and air conditioning, aerosol sprays, and foam packaging industry.
• Ozone contributes to 3 – 7% of Greenhouse effect. The largest net source of tropospheric ozone is influx from the stratosphere. Large amounts of ozone are also produced in the troposphere by photochemical reactions, the amounts increasing with high levels of air pollution.

Unfortunately, recent human activities such as burning fossil fuels to run automobiles, heat homes and businesses, and power factories are causing increased concentrations of greenhouse gases, thereby resulting in more heat being trapped. The planet is losing less heat and, as a result we are beginning to experience Global Warming.

Estimates indicate there has been a 25% increase in $C{{O}_{2}}$concentration in the last 100 years and this is expected to double in the next 50 years, e.g. Brazil alone contributes billions of tons of$C{{O}_{2}}$, every year due to deforestation.

Ozone depletion

Ozone $({{O}_{3}})$ is a gas found throughout the atmosphere, but most highly concentrated in the stratosphere, between 10 and 50 above the sea level, where it is known as the “Ozone layer”

• This Ozone layer forms a protective shield for the earth from the harmful ultra-violet radiation from outer space, particularly UV– B rays which affects DNA molecules, causing damage to the outer surface of plants and animals and also marine life. In humans it causes skin cancer, eye cataracts and is a general immune - suppressant.
• “Ozone Holes” were first discovered over Antarctica by me British Antarctica Survey in 1983. Levels of ozone are dropping very fast, resulting in parts of the layer becoming thin and 'holes' developing because only a small percentage of 0, gets naturally replenished every year.
• In 1974, Mario Molina and Sherwood Roland of the University of California discovered that a group of synthetic chemical substances known as CFCs and HCFCs destroy ozone in the stratosphere. These chemicals are inert, non-flammable, non-toxic, and lighter than air and can remain intact for years. They contain Chlorine and Fluorine, common being CFC – 11, CFC– 12, CFC – 22 and CFC – 13.
• ‘Halons’ containing 'Bromine' and used in the fire- fighting industry, are 100 times more potent than CFCs. CFCs are commonly used in Air-conditioners and the Refrigeration industry (Freon gas), aerosol propellants (in perfumes and deodorants), in the foam packaging industry Styropor, Thermocol) and as solvents for greases and glues.
• The ozone ${{O}_{3}}$ found in upper part of the atmosphere, i.e. Stratosphere, is Good ozone, since, it acts as a shield for absorbing UV – radiations from sun. The UV rays are highly injurious to living organisms. The DNA and Proteins of living organisms preferentially absorb UV rays. These high energy rays break the chemical bonds of these polymers. The ozone that is formed in lower ionosphere, i.e., Troposphere, is Bad ozone, since, it harms plants and animals.
• Compounds like Carbon Tetrachloride and Methyl Chloroform are also found to release Chlorine (Halogens) which ultimately destroy the stratospheric Ozone.
• Du Pont (USA) and ICI (UK) have developed certain substitutes like HFC (Hydro fluorocarbon) and HCFC (Hydro-Chloro-Fluoro Carbon), e.g. HCFC-123 which contain less Chlorine than CFC, but these are not effective, permanent solutions.
• Cheaper alternatives for refrigeration being developed are Propane and Ammonia as coolants, which are completely environment friendly.

Unit for Ozone Thickness

The thickness of ozone in a column of air, from the ground to the atmosphere, is measured in Dobson units. (1 – Dobson unit = 10 urn thickness of ozone under standard temperature and pressure.) The term Dobson is after the name of Gordon Dobson of Oxford University. When the ozone thickness becomes less than 220 DU it is considered as thinning of ozone or the ozone hole.

Deforestation

The process of clearance of forest by burning or logging is called deforestation. The main reasons for deforestation are trees or derived charcoal are used as, or sold, for fuel or as a commodity, while cleared land is used as grassland for livestock, plantations of commodities, and settlements. Deforested areas usually sustain extensive adverse soil erosion and regularly damage into wasteland.

Causes of deforestation

There are numerous causes of deforestation such as

(i) Expansion of farming land

(ii) Logging and fuel wood

(iii) Overgrazing

(iv) Fires

(v) Mining

(vi) urbanization/Industrialization and Infra-structure.

(vii) Air Pollution

(viii) Wars and role of military

(ix) Tourism

(x) Over population and poverty

(xi) land rights, land tenure and inequitable land distribution resources

(xii) Economic, i.e. development/land conversion value, fiscal policies, etc.

(xiii) Under valuing the forest

(xiv) Corruption and political cause

 Jhum Cultivation (Slash and Burn Agriculture) In North- East states of India Jhum cultivation has been responsible for deforestation. The farmers cut-down the trees of forest and burn the plant - remains. The "land' so developed is use for farming or cattle grazing, and 'ash' is used as fertilizer. After cultivation, the area is left for several years so as to allow its recovery. The farmers then move on to other forest areas and repeat the process. During earlier days of Jhum cultivation enough time- gap was given for land - recovery from the effect of cultivation. Later, with increasing population, and repeated cultivation, the recovery phase was done away, and this resulted with deforestation.

Strategies to reduce deforestation

Strategies to reduce deforestation should be a combination of pro-active role of national, state, municipalities, civil societies and private sector in the following ways-

(i) Reducing Population growth

(ii) Reducing emissions from deforestation and forest

(iii) Increase the area and standard of management of protected areas

(iv) Increase the area of forest reserved for timber production

(v) launch the mass awareness programme regarding value of forest.

(vi) Encouraging substitutes

(vii) Increase area of forest plantation

(viii) Government initiatives through policies and action-plan

(ix) Participatory forest management and rights

(x) Increase investment in research, education and extension

(xi) Improve the information base and monitoring

Reforestation

It is the process of restoring a forest. Though the reforestation may occur naturally in a deforested area, but it is speeded up by planting the forest trees. (Please remember that the management of forests for the benefit of the entire ecosystem is called Silviculture. The Forestry, on the other hand, is the practice of growing and managing forest trees for the production of commercial timber).

Forest Conservation

In people- participation, for the conservation of forests, therole of Bishnois and Garhwalis has been exemplary.

Amrita Devi (Bishnoi) and her 3- daughters sacrificed their life for the cause of environment. For them the Trees mattered more than their own life.

Similarly, the local women of Garhwal Himalaya, protected the trees by hugging them. This is popularly known as Chipko Movement (1974).

Government of India has recently announced 'Amrita Devi Bishnoi Wild life Protection Award' for the individuals or communities from the rural area who have courage and dedication in the protection of wildlife.

Looking to the participation of local people, the Government of India in 1980, also introduced the concept of 'Joint Forest Management' (JFM) for the protection and management of the forests. From such projects the rural communities get the benefits of forest products, like. Rubber, Gum, Resin and Medicinal products etc. and thus, conserve the forests in a sustainable manner.

Human population has increased enormously in the last century due to which the demand of food, water, home, electricity, roads and automobiles etc. has increased many fold. These demands are creating tremendous pressure on the natural resources and causing environmental pollution (of Air, Water and Soil etc.) On one hand we need to check the degradation and depletion of natural resources, and on the other the level of Pollution is to be controlled without halting the process of development.

Pollution is an undesirable change in physical, chemical or biological characteristics of air, land, water or soil. The agents that bring about such an undesirable change are called

Pollutants.

For the classification of pollution/ pollutants various parameters are used,

• On the basis of the part of environment affected - e.g., Air pollution, water pollution, soil pollution, etc.
• On the basis of origin of pollutants e.g., Natural pollutants and Anthropogenic pollutants
• On the basis of physical nature of pollutants - e.g., Gaseous pollutants, particulate pollutants (dust, smoke soot)
• On the basis of ecosystem - e.g., Biodegradable pollutants and non-biodegradable pollutants
• On the basis of release process - e.g., Primary pollutants, secondary pollutants
• On the basis of forms -e.g., Radioactive pollutants, plastic pollutants Toxic pollutants

To improve the quality of environment (air, water and soil), and control pollution, the Government of India passed Environment (Protection) Act in 1986.

Air Pollution

Air pollution is defined as the presence of any liquid, gaseous or solid substance which includes noise and radi active radiation in the atmosphere in such concentration that may be directly and indirectly injurious to human or other living organisms, plant property or interferes with the normal environmental process.

The main issue among environmentalists and researchers especially in developed countries is air pollution.

• The main pollutants of air pollution are particulate mane PAHs, lead, ground-level ozone, heavy metals, Sulphur dioxide, benzene, carbon monoxide and nitrogen dioxide.
• Air pollution is also responsible for climate change due to the higher greenhouse effect, acid rain, and the depletion of the ozone layer that constitute important global environmental problems.
• Air pollution is the main reason of ill health and death natural and man-made sources.
• Tobacco smoke, house cleaning items, insecticide industries, automobiles, power generation, combustion of solid fuels for cooking, poor maintenance of cars and other automobile, etc. are the main cause of air pollution
• Air pollution can be of two types: indoor and outdoor.
• Indoor air pollution is restricted to buildings only. It is the amount of chemical, biological and physical contaminants in the air inside a building. Building materials, central heating and cooling devices, painting colours, stoves gas heater, and tobacco smoke, etc. are the examples indoor air pollution.
• Release of several air pollutants into the atmosphere which causes severe threat to living organisms or upset the functioning of environment is called outdoor pollution.

Outdoor air pollution

• Outdoor air pollution constitutes of the air pollution which is caused outside one buildings for example, burning garbage, vehicles, etc.

Contributors of Pollutants

• There are natural pollutants of air like animal decay.
• Volcanic eruptions release more sulphur fumes than all power plants and all industries in the world.
• Lightning bolts create nitrogen oxides just as automobiles and industrial furnaces do.
• Trees emit hydrocarbons called terpenes causing bluish haze.
• The major cause of air pollution, at least in the metro cities, is the increasing number of automobiles.

Effects

• There is mounting evidence that our whole planet is affected by pollution. The South Pole seems fairly clean because 90 % of earth's population lives in northern Yet in 1985 scientists detected a major hole in protective ozone screen over Antarctica.
• The North Pole, on the other hand, resembles a cool town. In winter when the Arctic is tilted into long nights and the sun cannot generate cleansing winds and precipitation, the largest single mass of pollution sits atop the globe like a dirty cap composed of mixture of gases and particles, sulphates and soot.
• Tracing pollutants has become a vital necessity as air currents do not follow political boundaries. Many countries are blaming their neighbors for polluting their air space. Air pollutants weaken the trees and then they are killed by drought and pathogens. Trees weakened by climatic variations are finished off by air pollution. Perhaps the most controversial issue of the decade is acid We are trying to understand the full effects on an atmosphere acidified by burning fossil fuel.

For millions of years the ingredients of such substances have been cycling through the ecosystem, constantly changing their form. They pass in animal and plant tissues, sink in sea, return to the earth and are vaulted aloft in some geologic event to begin the cycle again. An atom of oxygen completes this cycle generally once in 2000 years. We are in the midst of a chemical revolution in which around 65,000 commercial compounds enter our environment each year. Some are proven carcinogens. A modern city suffers from many air pollutants which form a complex mixture of smog.

 Sr. No. Pollutant Origin Effect 1. Arsenic (As) Coal, oil furnaces, glass factories Lung and skin cancer 2. Benzene $({{C}_{6}}{{H}_{6}})$ Refineries, motor vehicles Leukemia 3. Cadmium (Cd) Smelters, coals, oil furnaces Damage to lung, kidney, bones 4. Chlorine (CI) Chemical Industries, volcanic activities Causes irritation 5. Carbon monoxide (CO) Motor vehicles, smelters, coal steel plants Starves body of oxygen, damages heart 6. Fluoride (F) Smelters, steel plants Mottles teeth in children 7. Hydrocarbons Unburnt gasoline fumes, motor vehicles Combines with nitrogen oxides in sunlight to form smog, 8. Formaldehyde (HCHO) Chemical plants Allergenic, carcinogenic, headaches, burning sensation in the throat, and can aggravate asthma symptoms 9. HCI (Hydrogen chloride) Incinerators Irritates eyes and lungs 10. Hydrogen fluoride (HF) Fertilizer plants smelters Irritates skin, eyes, mucous membrane 11. Mercury (Hg) Coal, from $N{{O}_{2}}$ causes acid rain Tremors, nerve troubles 12. Nitric acid  $(HN{{O}_{3}})$ Formed from $N{{O}_{2}}$ causes acid rain Respiratory diseases 13. Nitrous acid $(HN{{O}_{3}})$ Formed from $N{{O}_{2}}$ and water vapour Respiratory disease 14. Hydrogen sulphide $({{H}_{2}}S)$ Refineries, Pulp mills Nausea, irritates eyes 15. Sulphuric acid $({{H}_{2}}S{{O}_{4}})$ Formed from $S{{O}_{2}}$in sunlight with Respiratory diseases hydroxyl inos 16. Manganese (Mn) Steel and sulphur dioxide power plants Parkinson?s diseases 17. Nickel (Ni) Smelters, coal, oil Lung Cancer furnaces 18. Nitric Oxide (NO) Motor Vehicles, coal, oil furnaces Oxidizes to $N{{O}_{2}}$ 19. Nitrogen dioxide $(N{{O}_{2}})$ Formed in Sunlight from NO Bronchitis Loss of resistance to influenza forms Ozone 20. Ozone $({{O}_{3}})$ Ground level ozone formed from nitrogen oxides $(N{{O}_{x}})$and volatile organic compounds (VOCs) Asthma, irritates eyes sunlight from nitrogen oxides and hydrocarbons 21. Lead (Pb) Motor vehicles, high smelters Brain damage 22. Silicon Tetra fluoride $(Si{{F}_{4}})$ Chemical plants Lung diseases 23. Sulfur dioxide $(S{{O}_{2}})$ Smelters Coal, Oil furnaces Irritates eyes, breathing problems

Prevention of air pollution

Air pollution can be reduced with the help of-

(i) using smokeless sources of energy like smokeless stoves, biogas, solar and wind energy

(ii) using devices for filtering smoke in chimneys of factories and power houses

(iii) Planting more trees

(iv) Locating industries away from residential areas

(v) Strictly checking pollution levels in automobiles exhaust emission by using catalytic converter.

(vi) Using CNG

Auto Fuel policy

 The vehicular emission norms were introduced in India in year 2000 and in the same year Bharat Stage norms were adapted. The Bharat stage II, equivalent to Euro II norms, was made applicable in 11- cities, i.e. Agra, Ahmadabad, Bengaluru, Chennai, Delhi, Hyderabad, Kanpur, Kolkata, Mumbai, Pune and Surat. It had to be applicable to all automobiles throughout the country from April 1st 2005. From 1st April 2005, all automobiles had to meet Euro III emission specifications in the above 11- cities. By 1st April 2010, they had to meet Euro IV norms. The rest of the country, by 2010, had to meet Euro III emission norms for automobiles and the fuel. According to the norms of Euro III the sulphur was to be controlled at 150 ppm (parts per million) in petrol, and 350 ppm in diesel. The aromatic hydrocarbon were to be regulated at 42 % of the fuel. The goal was to reduce sulphur to 50 ppm and hydrocarbon to 35 % of the fuel. According to the corresponding fuel the vehicular engines were also needed to be upgraded. Bharat Stage- IV (BS-IV) in certain States and Union Territories is to be introduced on 1st April, 20l6, and in the rest of country on 1st April, 2017. In March 2017, supreme court of India banned the registration of BS-III vehicles in New Delhi. BS-V emission norms for vehicles across me entire country will be implemented from 2019. BS-VI for four wheelers will be enforced in India from year: 2023.

Water Pollution

• Water pollution is a kind of pollution which involves the contamination of water sources or bodies on which several aquatic animals depends on for their life support.
• Polluted water comprises of Industrial discharged wastes, sewage water, and rain water pollution.
• Quality of soil and vegetation is affected by the polluted water. Pollutants in water comprise a extensive kind of chemicals, pathogens, and physical chemistry or sensory changes. Many of the chemical substances are toxic or even dangerous.
• Pathogens can produce water borne disease in humans and animals.
• Polluted water is discharged in water polluting the aquatic flora and fauna.
• Washing clothes near lakes and rivers is one of the reason of water pollution since, detergents cause a condition called “Eutrophication” which blocks sunlight from entering inside that water body thus reducing oxygen standards in the water and causing an inhabitable environment.

Types of Water Pollutants

• Physical pollutants -g. Hot water. Oil spill
• Chemical pollutants -g. inorganic compounds (Nitrates, phosphates and fluorides, etc.) Biocides and Heavy metals (Hg, As, Pb, Cd etc.)
• Biological pollutants -g. Bacteria, protozoans, viruses, helminthes and other pathogens.

All domestic sewage and industrial effluents, without being treated, are dumped into nearby river.

Types of Water Pollution based on causes &

Pollutants

1. Sewage

Even 0.1 % of impurities by sewage, makes the water unfit for human use. These impurities of domestic sewage may include

• Suspended solids - e.g., Sand, silt and clay
• Colloidal materials - e.g., Faecal matter, bacteria and fibres of cloth and paper
• Dissolved materials - e.g. Nutrients like Nitrates, phosphates, sodium, calcium and ammonia etc.

The solids from such sewage are easy to remove by physical treatment but the removal of nutrients, toxic metal ions and organic compounds is difficult. (In municipal waste, the detergent residues have excess phosphates, and the organic remains have excess nitrates.)

The presence of a large amount of nutrients in water also causes excessive growth of planktons or free floating algae to produce Algal bloom. Such algal blooms

• Deteriorate the quality of water
• Cause the mortality of fishes
• Imparts distinct colour to water bodies
• May be extremely toxic to human beings and aquatic animals

1. Industrial Wastes

Unlike domestic sewage, the waste water from the industries, like chemical industry, paper industry, petroleum industry and metal extraction and process industry, often contain toxic substances like, heavy metals and variety of Organic compounds (e.g., DDT).

Some toxic substances of industrial waste- water may undergo biological magnification (Bio-magnification) in the aquatic food chain. Since such toxic substances cannot be metabolized or excreted. They get accumulated in the organisms and from there they pass on to the next higher trophic level.

The increase in the concentration of the toxicant at successive trophic levels is called Bio-magnification. This phenomenon is well known for DDT and Mercury.

The high concentration of DDT in fish - eating birds due to bio-magnifications of DDT in aquatic food chain has resulted in

• Disturbance in the Calcium metabolism
• Thinning of egg -shell, causing premature hatching of chickens
• Decline in birds- population

III. Hot Water

Another important category of pollutant is heated waste water, released from electricity generating units, like thermal power plants. Such thermal water damages aquatic fauna and flora (Thermal Pollution). It also reduces the number of temperature sensitive organisms. Besides, the thermal waste water also reduces the amount of dissolved gases. However, in extremely cold area, such water may enhance the growth of plants and fishes.

There is ageing of water bodies in nature which affect the aquatic ecosystem. Such natural ageing of a water body due to biological enrichment of its water, leading to depletion of species diversity, is called Eutrophication.

• A young lake has cold and clear water supporting little life.
• With the time, the streams draining into lake introduce the nutrients like, Nitrogen and Phosphorus, which encourage the growth of aquatic fauna and flora.
• When the lake fertility increases, the plants, animals and the micro- organisms multiply very fast and organic remains begin to be deposited at the bottom of the lake.
• Over the centuries, the organic debris and silt pile up and the lake becomes shallower and warmer. The warm water organisms now replace the cold water organisms.
• The marsh plants, now, begin to fill the original lake. This later gives the way to large masses of floating plants (Bog) which finally converts the lake into land.

The natural ageing of a lake depends upon climate, size of lake and other factors, normally taking thousands of years.

The ageing process can however, be accelerated by the transportation of pollutants from homes, agricultural fields and industries due to human activities. Such wastes may poison the whole population of fish and the decomposing- remains further deplete the dissolved oxygen content, and the lake can literally choke to death. This phenomenon of choking of lake is called Cultural or Accelerated Eutrophication.

Oil Spills/Pollution

The oil spill is an accidental discharge of petroleum in ocean or estuaries causing oil pollution of marine ecosystem.

The oil exploration, oil refineries and offshore oil mining contribute to oil pollution affecting planktons, fish and marine birds. The oil, being lighter than water, spreads as a thin film which is called an ‘Oil slick’. The oil slick is also harmful to coral reefs.

 Integrated Waste- Water Management - A Case Study   The waste water including sewage can be treated in an integrated manner by utilizing a mixture of artificial and natural processes. Such an initiative was taken by the people of the ?Town of Arcata? along the biologists of Humboldt State University and created an ?Integrated waste- water treatment system?. This included 1. Conventional method of sedimentation, filtering and chlorine treatment 2. The development of a series of 6- connected Marshes (over 60 hectares of marshland) In such marshes, with the help of biologists, appropriate plants- fungi, algae and bacteria etc. were seeded. Such organisms neutralized, absorbed and assimilated the dangerous pollutants or toxics, like dissolved heavy metals. The water that passed through these marshes got naturally purified. These marshes also constituted a Sanctuary with a high level of biodiversity from fishes to birds- mammals. A group of people, called FOAM (Friends Of the Arcata- Marsh) are responsible for up keeping and safeguarding this projects.

Ecological Sanitation (Eco San)

Generally a lot of water is required for the removal of wastes. We use tremendous amount of water to flush the toilet.

The Eco San is a sustainable system for handling human excreta or faecal matter by using dry 'Composting Toilets'. Such toilets are very useful for the rural areas where sewer systems are not possible and water supplies are very limited. These toilets are hygienic, efficient, practical and cost effective for the disposal of human waste. With this method the human excreta can be recycled into natural fertilizer (a resource) which lessens the load of chemical fertilizers.

These Eco San recycle water and organic nutrients of human wastes back into the local environment. Thus such sanitation systems

• Protect the environment and conserve the water
• Prevent diseases by minimizing the entry of pathogens in to water cycle, and thus promote health.
• Recycle the nutrients and organic matter

Such Eco San are already working in Kerala and Sri Lanka.

Diseases caused by Water Pollution

The most common water pollution diseases involve digestive system and infectious diseases, it may cause many others like-

(a) Infections diseases caused by pathogens from animal fecal origins involving: - Typhoid, Giardiasis, Amoebiasis, Ascariasis, Hookworm

(b) Diseases caused by polluted beach water: - Gastroenteritis, Diarrhea, Encephalitis stomach craps and aches, vomiting, Hepatitis, Respiratory infections

(c) Liver damage and cancer caused by chlorinated solvents, MTBE.

(d) Kidney damage caused by a series of chemicals found in contaminated water.

(e) Neurological problems due to pesticides (eg. DDT)

(f) Reproductive and endocrine damage

(g) Bathing in polluted water causes rashes, ear aches and pink eyes.

Water Pollution treatment

Water can be treated by many ways, i.e. denitrification, industrial treatment, Septic tank and Ozone waste water treatment. Raw sewage should be treated in water treatment plant before releasing it in environment. In water treatment plant sewage goes through many chambers and chemical processes which reduce its toxicity. Denitrification is an ecological method to prevent the discharge of nitrates in soil, and stops ground water pollution with nutrients. Septic tanks treat sewage at the place where it is located and used to treat sewage from an individual building. Untreated sewage from a property streams into the septic tank and the solids are separated from the liquid. Breaking of pollutants into water sources is done by ozone generator. By using Ultraviolat radiation and Electric discharge field oxygen is converted into ozone by the generators.

BOD (Biochemical Oxygen Demand)

BOD (Biochemical Oxygen Demand), also known as referred to as biological oxygen demand, is a test performed to measure the potential of wastewater and other waters to deplete the oxygen level of receiving waters. In other words, the BOD test is performed to determine what effect dirty water, containing bacteria and organic materials, will have on animal and plant life when released into a stream or lake. When there is an abundance of bacteria and organic materials, the bacteria will take in oxygen in order to breakdown these molecules. If bacteria are taking in large amounts of oxygen, this will have a detrimental effect on the surrounding ecosystem. On the contrary, when there are low levels of organic waste in the water, there are fewer bacteria present, the BOD will be lower and the dissolved oxygen levels higher. In wastewater treatment plants, they often calculate the percentage removal of BOD to determine the efficiency of the treatment process. For this reason, BOD is sometimes referred to as a water contaminant.

A BOD level of 1-2 ppm is considered very good. The will not be much organic waste present in the water supply. A water supply with a BOD level of 3-5 ppm is considered moderately clean. In water with a BOD level of 6-9 ppm, the water is considered somewhat polluted because there is usually organic matter present and bacteria are decomposing this waste. At BOD levels of 100 ppm or greater, the water supply is considered very polluted with organic waste.

A pH of 6.5 to 8, 2 is optimal for most organisms. Rapidly growing algae or submerged aquatic vegetation remove $C{{O}_{2}}$ from the water during photosynthesis, significantly increasing pH levels, pH levels > 9.0 begin to be harmful to salmonids (trout) and perch. Rainwater naturally has a pH of 5.5; pH < 5.5 is harmful to freshwater shrimp, snails, and clan metals normally trapped in sediments may be released into the acidified water.

Acidic < 6.5 pH                       Basic > 7.5 pH

Sound Pollution

In India, the Air (Prevention and control of pollution) A came into force in 1981 and in 1987 it was amended to include Noise as an Air pollutant. Unwanted sounds created by humans, animals and machines which disturbs the environment and humans is called as sound pollution. The word noise comes from the Latin word nausea meaning seasickness.

Sources of Sound

The main source of noise is transportation system including rail noise, aircraft noise and vehicle noise. People leaving a factories experience sound pollution because of the unwanted sounds coming from factories. Other sources of sound pollution are car alarms, emergency service sirens, office equipment, factory machinery, construction work, grounds keeping equipment, barking of dogs, appliances, power tools, lighting hum, audio entertainment systems, loudspeakers, and noisy people. Use of loudspeakers for political purposes and other purposes is also the cause of sound pollution.

Measurement of sound

Sound pollution is measured in decibels. Humans can't sleep at 45 decibels; hearing begins to damage in 85decibels and pain in ears start at 120 decibels.

According to 'Central pollution control board', the permissible ambient noise levels are

 Day time Night time Industrial 75 dB 70 dB Commercial 65 dB 55 dB Residential 55 dB 45 dB Silent zone 50 dB 40 dB

A brief exposure to extremely high level of sound$(\underline{>}-150\,\,dB)$, generated by taking off of a jet- plane or rocket, may damage ear drums and hence can impair hearing ability permanently. The same may also happen from prolonged exposure to even lower noise level.

Effects of Sound pollution

Health and behaviour of humans are disturbed by the noise pollution. Unwanted sounds can damage physiological and psychological health. Sound pollution can cause annoyance and aggression, hypertension, high stress levels, tinnitus, hearing loss, sleep disturbances, and other harmful effects. Due to increase in sound level there can be lack of concentration at work which can lead to low productivity and performance. High sound levels can increase in cardiovascular effects in humans which is very dangerous for health.

 Central Government?s Regulation & Control of Noise Pollution   These regulations are meant for the following: (i)  Implementation of noise standards in different zones/areas. (ii) Restrict the use of loud-speakers. (iii) Restrict the over-usage of horns, sound creating equipment?s for construction and fire-crackers. (iv) Allotting responsibility to state pollution control boards and central pollution control board to provide data about the noise pollution, so that measures may be taken to control noise pollution.

Control of Noise Pollution

• For reducing industrial sound the Mufflers or the sound absorbent materials can be used.
• The Horn free zones around hospitals and schools can be created.
• Low level of sound can be permitted for crackers and loudspeakers.
• Fixing the time for playing loud speakers, after which they cannot be played.
• Stringent laws should be framed to implement and observe the noise level.
• Planting the trees or dense hedge plants, that act as noise barriers.
• Proper maintenance or lubrication of machines.

Agro-chemicals & effect

Agro chemicals are developed by the use of modern technologythat depends on inorganic fertilizers and pesticides. Excess useof these fertilizers can lead to immediate harmful effect orcan also be long lasting. Although many benefits are there bythe use of agro chemicals which are related to increase yieldof plants and animal crops and less wastage during storing.These profits are substantial. In combination with geneticallyenhanced varieties of crop species, agrochemicals have madesignificant contributions to the accomplishments of the "greenrevolution." However there are certain environmental andecological damages also related to the use of agro chemicals.For example excess use of fertilizers can contaminate the groundwater with nitrate, making it unfit for the consumption of humansand livestock. If there is large concentration of nitrogen in waterit can poison animals by immobilizing some hemoglobin in bloodand hence reducing the ability to transport oxygen. However ifthe fertilizers are in the water such as streams, lakes, etc. cancause an increased productivity of those aquatic ecosystems, aproblem known as eutrophication. Due to eutrophication therecan be excessive growth of algae, wide mortality of fish andother aquatic animals and a bad taste of water.

There can be many environmental problems due to the use of pesticides. As we all know that pesticides are used to reduce the abundance of species of pets. But while using pesticides humans also come in contact with them which are harmful to them. When the entire fields are spayed with pesticides by the use of tractor or airplane or helicopter many non-targeted organisms come in contact with the pesticides. This happens on the treated site, and also on nearby off-sites as a result of "drift" of the sprayed agrochemical. These non-target contacts cause several unnecessary poisonings and deaths of organisms that are not agricultural pests.

There are global contaminators of environment with pesticidessuch as DDT, Dieldrin, and Aldrin. This contaminationincludes the extensive presence of pesticide residues in almostall wildlife, well water, food, and even in humans. Residuesof some of the chemicals used in animal husbandry are alsothought by some people to be a problem, for example, whentraces of antibiotics and bovine growth hormones arise inconsumer products such as meat or milk.

The worst examples of the use of pesticides are the use of DDT.Modern use of pesticides includes the use of pesticides that areless persistent than DDT and related chlorinated hydrocarbon.However humans are also at the risk of the use of somepesticides. There are about almost one million pesticidespoisoning all over the world with nearly 20,000 fatalities.About one-half of the human poisonings happen in poorer,less-developed countries, even though these places account foronly 20% of the world's use of pesticides. This is due to theilliteracy in these countries and to negligent enforcement ofregulations about the use of pesticides.

Example of the damage cause by the pesticides to humans includes Bhopal tragedy in India which occurred in 1984, in the area of a factory that was manufacturing an agricultural insecticide. In that case, there was an accidental discharge of about 45 tons (40 tonnes) of deadly methyl isocyanate vapor to the atmosphere. This agrochemical-related emission caused the deaths of about 3,000 people, and more than 20,000 others were seriously injured.

Researchers are continuously searching for non-chemical means of dealing with several of these agricultural requirements. Organic methods are been invented in enhancing the soil fertility and dealing with pests. Therefore, modem agricultural industries will continue to depend on heavily on the use of agrochemicals to achieve their problems of fertility, soil quality, and pests.

 Organic Farming - A Case Study   The? integrated organic farming? is acyclic and zero waste procedure in which the waste products of one process are cycled to be used as nutrient for the other processes. Such faming allows the maximum utilization of the resources and increases efficiency of production. Mr. Ramesh Chandra Dagar, a farmer in Sonipat (Haryana) has started integrated farming that includes a chain of processes like- Bee keeping, agriculture, Dairy farming, Water harvesting and Composting etc. The Processes support each other and make the project extremely economical and well sustainable. Following are the advantages of such farming ? ·         There is no need of chemical fertilizers for crops. ·         The cattle ? dung is used as manure. ·         The crop waste is used to create compost. ·         The so formed compost is used as a Natural fertilizer. ·         The compost is also used to generate ?Natural gas? for the energy needs of the farmers. Mr. Dagar has also created ?Haryana Kisan Welfare Club? to spread the idea of organic farming..

Acid Rain

Acid rain is a rain or any other form of precipitation that is unusually acidic, meaning that it possesses elevated levels of hydrogen ions (low pH). The term "acid rain" was coined in 7872 By Robert Angus Smith, after a link was established between sulfur dioxide $(S{{O}_{2}})$ coal in Manchester and acidification of nearby rainfall. Rainfall with pH less than 5.6 is called Acid rain.

Sources of Acid Rain

Acid rain is caused by a chemical reaction that starts when sulfur dioxide and nitrogen oxides are released into the air.

• These compounds can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, called as acid rain. Sulfur dioxide and nitrogen oxides are highly soluble in water and can be carried very far by the wind.
• Consequently, the two compounds can travel long distances where they become part of the rain, sleet, snow, and fog that humans experience on specific days.
• Though there are few natural causes also for acid rain, but still human activities are considered to be the main cause of acid rain.
• During last few decades, human beings have released various chemicals into the air, which has altogether changed the composition of gases in the atmosphere, Power plants release huge amount of sulfur dioxide and nitrogen oxides when they burn fossil fuels, like coal, produce electricity. Additionally, the exhaust from light and heavy vehicles releases nitrogen oxides and sulfur dioxide into the air. These pollutants are the main cause of acid rain.

Effects of Acid Rain

• Acid rain leads to acidification of water bodies such as lakes and streams. It contributes to the damage of trees at high elevations (e.g. red spruce trees at the height of 2,000 feet and above) and many sensitive forest soils.
• Additionally, acid rain stimulates the decay of building materials and paints. Before reaching the earth, sulfur dioxide and nitrogen oxide gases and their particulate matter derivatives (sulfates and nitrates) lead to visibility degradation and harm people health.
• Acid rain has been held responsible for ruining the marble walls and pillars of one of the Seven Wonders of the World, Taj Mahal in India.
• Acid rain reacts with calcium to form calcium bicarbonate, which can be easily washed away.
• Paul's Cathedral in London and the Statue of Liberty in New York are known to be few victims of acid rain. As the concentration of Sulphur dioxide is increasing in the air of Delhi, there may be a danger of corrosion of the Red Fort and similar other historical buildings and monuments made up of stones.

In Calcutta also, architectures such as the marble-built Victoria Memorial Hall may be in similar danger in the near future.

Measures to control Acid Rain

Some of the major procedures that must be followed to control acid rain are as follows:

• Reduce amount of sulphur dioxide and oxides of nitrogen released into the atmosphere.
• Use cleaners fuels
• Flue (waste) gas desulphurization (FGD)
• Use other sources of electricity (i.e. nuclear power hydro-electricity, wind energy, geothermal energy, and solar energy).
• Reduce the effects of Acid Rain by liming the soil and water

Solid Waste Management

Solid waste management is one of the major challenges faced by many countries around the globe. Inadequate collection, recycling or treatment and uncontrolled disposal of waste in dumps can lead to severe hazards, such as health risks and environmental pollution.

No other pollutant is discussed about more vociferously among environmentalists, politicians and the people at large than the garbage which is the bulky plastic and refuse heap variety trash that accumulates in different corners of the cities. These piles are quite often taller than the city halls. What we throw away is the closest we come to the pollution problem as we rarely see the acid rain or spot those CFCs.

The growing accumulation of garbage reduces the land values, increases truck traffic, and ruins health, aesthetics and the necessities of life - the air we breathe and the water we drink.

Sources
Solid waste refers to the non-liquid waste materials arising from domestic (garbage debris and night soil) activities, trade and commercial activities (hazardous and non-hazardous) industrial activities, agricultural activities, mining and public services (office and hospital wastes).

Ejects

It may be emphasized that unsanitary disposal and utilization of wastes result in high incidence of illness and death from faecal borne diseases. The faecal borne diseases are bacillary dysentery typhoid fever and enteritis. Therefore, it is necessary to provide adequate and sanitary measures of disposal of wastes.

Types of Wastes

Urban wastes are discarded as organic and inorganic substances in the form of solid, semi-solid, liquid and gases, which are residues or derivatives of human, vegetable material and industry. These wastes are broadly classified into the following categories:

• HOUSEHOLD WASTES: Waste generated in the preparation and consumption of food, human excreta,
• COMMERCIAL WASTES: These wastes include a high proportion of paper, cardboards and plastics. They result from activities in office buildings, stores, markets, theatres, hospitals, and restaurants.
• INDUSTRIAL WASTES: Wastes due to different types of production activities. This category of waste, contains, hazardous wastes that are harmful to human beings and hence should be stored and treated separately.
• EFFLUENT WASTES: Domestic as well as industrial effluents that contaminate river water if allowed to flow unchecked.
• CITY WASTES: All the waste resulting from the maintenance of streets, roads, parks, and schools, paper, dry leaves, animal wastes, sludge, carcasses of small animals and slaughter house wastes. The responsibility of the solid waste management department is only to look after the disposal of domestic wastes, city wastes and the domestic sewage.

Method of Collection

The 90% of the refuse is collected from refuse bins and 10% of the refuse is collected by house to house collection method, as described below.

• Refuse storage which may sometimes require delivery of refuse by the householder over a considerable distance.
• Where the householder delivers the refuse to the vehicle at the time of collection.
• Door-to-door collection, where the collector enters the premises and collects the refuse and the householder is not involved in the collection process.

Radioactive waste which arises from civil nuclear activities as well as from defense related nuclear weapon activities, poses a terrible problem for handling and keeping the environment to be safe to the present and future generations. The techniques used emphasizes on waste minimization and volume reduction. Nuclear waste is categorized into high, intermediate and low levels depending on the level of radioactivity in it.

Spent fuel is stored for long time to reduce the level of radioactivity in it and then reprocessed at reprocessing plants for gathering fissile elements. The generation of high level waste is at reprocessing plants. The amount of this waste in our country is much lesser due to our adoption of the closed fuel cycle. High level waste produced from the reprocessing plant is vitrified into a glassy form, enclosed in multiple barrier vessels and stored for a temporary period of three to four decades in engineered vaults with essential observation services. After cooling down in these storage facilities, waste vessels will be stored for long term in deep geological repositories.

Reprocessing and Waste Management plants are currently being operated by Bhabha Atomic Research Centre (BARC).

Harmful Effects

Initially the use of nuclear energy was considered to be a non-polluting way for generating electricity. Soon it proved to have 2- serious problems-

• Problem of leakage
• Problem of storage and safe disposal

The accidental leakage occurred in the 'Three Mile Island' and 'Chernobyl'.

The nuclear waste is extremely potent pollutant. The radiation given off by nuclear waste is extremely damaging to biological organisms since it causes mutations at a very high rate. In lower doses, it creates various disorders, the most frequent of which is Cancer. In higher doses the nuclear radiation becomes lethal.

Radioactive wastes have the harmful effects in the following ways:

(i) Pollutes the earth to a dangerous level of toxicity.

(ii) Are absorbed in water and then enter in living beings through food chains.

(iii) Emit harmful radiations which damage cells, tissues and Red blood corpuscles (RBC).

(iv) Can cause cancer, leukemia, etc.

(v) Are threats for aquatic life.

Control Measures for Radioactive wastes

With respect to control of the materials composition radioactive waste can be grouped into:

(i) The treatment and packaging has to be performed according to a qualified process.

(ii) Conditioned waste produces being qualified with respect to the radiological requirements.

(iii) Legacy waste products need to be qualified by sport checking according to composition requirements.

Plastic Waste Management

Plastics have become an indispensable part of our daily lives. Invented in 1935, they are wonderful products of polymer chemistry produced from the by- products of petroleum refining. They are classified as into two main categories:

• Thermoplastics: They are substances that become plastic on heating. A plastic material can be repeatedly melted or softened by heat without change of properties. This property makes it possible to recycle the used plastic articles.
• Thermosetting plastics: Plastics that have once been subjected to heat and pressure, lose their plasticity.

Environmental aspects of Plastic Manufacturing

All the varieties of plastics are manufactured from petrochemical based hydrocarbons. These hydrocarbons, and the plastic manufacturing processes involved possess environmentally critical characteristics.

The raw materials and intermediate products used in the manufacture of Poly vinyl chloride (PVC) - Ethylene, Chlorine, Hydrogen chloride. Vinyl Chloride Monomer (VCM), and Ethylene Dichloride (EDC) - are known hazardous materials. Additives, fillers, and coloring pigments used in plastic goods can also exhibit hazardous properties.

Environmental issues

• Escape of gaseous hydrocarbons, chlorine, and hydrogen chloride gas into the atmosphere.
• Waste-water from the processes and wash-waters can carry pollutants.
• Dioxins can be liberated due to mishaps in the process.
• Most significant health and safety issue in the manufacture of PVC is the exposure of plant operators to Vinyl Chloride Monomer (VCM). In earlier days over exposure of workers to high concentrations of VCM was found to increase the risk of angiosar-coma of the liver - a rare cancer of the blood vessels of the liver. Exposure levels are now monitored and controlled; fugitive emissions are avoided by good house-keeping in the plastic industry, greatly reducing the VCM-related health problems.
• Fire hazards in plastic industry and in godowns storing plastic goods release toxic dioxins. PVC being a very widely used plastic in electrical cable insulation, and building construction has a high fire risk, one particular advantage of PVC is that it does not itself burn, but is charred by the heat of a fire. If there are no other fuels present; it will self-extinguish. This is one of the strengths of PVC in the electrical cabling and building construction industry.

Heavy-Metal Pollution from Plastics

Lead and cadmium compounds are added as stabilizers in PVC Manufacturing these chemicals are used in the manufacture of soft plastic items such as vinyl flooring sheets, soft toys, etc. increase their durability. Lead and cadmium can leach out during human contact, or when disposed in land-fills. Incineration of such rejected plastic items produces ash with high heavy met content. Use of lead compounds in the manufacturing process can be a potential hazard to workers in the PVC industry. Lead and cadmium are known neurotoxins and nephrotoxins respectively. Neurotoxins damage the nervous system, whereas nephrotoxins affect the kidneys. Strict adherence to process controls in industry, and quality control of products can greatly reduce the risk of heavy-metal pollution.

Nature of Plastics

Articles made of plastics are environment friendly if properly used and handled. Plastics are non-biodegradable because of their chemical structure. They cannot be bio-chemically decomposed by the microbes and as such, there is no threat of pollution. Being non-biodegradable they become virtually inert materials and remain in the environment for very long periods. They obstruct the natural and man-made activities in a physical way and do not easily participate in any reactions. These activities can be avoided by little care and common sense while discarding used plastics. That proves the fact that plastic, an 'environment friendly' product has been made an enemy by the callousness of humans. It is the misuse or abuse of plastic that is creating problems and not the plastics that are derived from the depths of Mother Earth.

The importance of plastic should be seen in their utility some of their uses and contributions to the environment are preseted below.

Negative effects of not using plastics, and using other materials

(i) Carry bags and packing amount environment

If paper is used in place of plastic, a great amount of biomsss has to be extracted either from Natural forests or commercial wood plantations for paper-making. In any case either environment loses greenery. Instead, the nutrients circulated these plants and trees could be used for producing food. Further manufacturing of paper in pulp and paper mills produces large quantities of highly polluting waste-waters, which are difficult and expensive to treat and clean of their pollution effects. If discharged without treatment they pose an equally big threat as that of unscientific discarding of plastics to the environment.

(ii) Food packaging using plastics

Milk Supply: In earlier days milk supplied in glass bottles which involved Jobs, like supply the milk and then next day to collect and transport back empty bottles to the dairy plant. Thus the glass bottles were adding to transportation cost and transport related air pollution problems. Now more milk can be transported per truck in plastic sachets whereas glass bottles used to occupy large space as they were bulky and heavy. Loading and unloading of milk bottles and empty bottles was also difficult, and required more labour. Elaborate washing of milk bottles for refilling was another big job. Bottle washing was consuming large quantity of scarce fresh water releasing highly polluted wastewater adding to water treatment costs. If charged without treatment wastes create severe pollution problems including odour. Use of plastic sachets for milk transportation has eliminated these problems. Earlier dairies used to receive complaints of milk getting spoiled due to improper washing of bottles, which does not happen with plastic sachets. Food packaging: food ingredients, precooked and ready to cook and use foods are widely available in the market and are popular in cities. Plastics are the mainstay of the packaged food industry.

(iii) Drinking water supplied in plastic bottle

Drinking water outside the home was a big menace earlier.It is recognized fact that drinking contaminated or unsafe wateris a cause for spread of contagious diseases.

Though expensive, packaged water bottles have reduced the risk of contamination.

(iv) In the field of medicine and health services

Before the advent of plastic injection syringes and needles, glucose bottles and many other glass appliances had to besterilized and reused in hospitals. There was always a risk of improper sterilization, which had the potential for spreading infection. This could have happened even in blood collected in bottled. Imagine the use of improperly sterilized glass articles in a scenario where HIV-AIDS infected patients are handled. Disposable syringes, blood sachets and many other hospital items made of plastic have greatly reduced the risks and hazards of contamination.

(v) Water supply pipes and Industrial piping Transportation of water in PVC pipes is very common as it has several advantages over conventional G1 Pipes.

• They are light and plumbing work is easy
• Corrosion problem is eliminated and hence corrosion related contamination of water is avoided and life of the pipes increases.
• Inner surface of pipes may be made smooth to reduce friction losses, thus saving on electricity bills and conserving energy. In industries whenever aggressive chemicals are to be transported PVC pipes of different varieties are used. PVC containers are commonly used for storage of water and many industrial chemicals.

(vi) Construction material

Plastics are extensively used as construction materials such as doors and windows house hold. Articles such as chairs, table holding racks, bucket and more. Use of plastics is reducing the burden on conventional materials such as wood and metals. If these are all the advantages of using plastics, why so much of a hue and cry is being raised about the ill effects of plastics on the environment? In this regard we have to recognize the fact that plastic is not the culprit; it is humans and society who, after use of plastics, discard them indiscriminately into the environment creating problems that are easily avoidable.

Problems Arising from Indiscriminate Discarding of used Plastics, particularly Carry Bags

Thin plastic carry bags are found strewn everywhere on land, water bodies and in drains. They have become a main component of municipal solid waste. Being non-biodegradable, they stay in the environment for very long periods. Several ill effects of these plastic items have been recognized:

• They choke storm water drains, often causing overflow of storm water on roads.
• Some people have a callous attitude of dumping solid wastes including plastic carry bags into the sewer system with utter disregard to the consequences. This happens when manhole covers are missing, extending an invitation for people to dump the garbage into them. The obvious effect is the choking of sewers.
• It is a common scene to sight floating plastic bags of various colours in vicinity of towns, preventing the entry of sunlight into the water, thus hindering, photosynthesis process, which is a source of oxygen supply for the fish Direct transfer of molecular oxygen into water is also affected. Another aspect of inadequate presence of dissolved oxygen in such water bodies is the development of anaerobic conditions leading to foul odours.
• Plastic carry bags often end up in agricultural fields directly or indirectly when domestic solid wastes stored in plastic bags are used as manure along with cattle During tilling they get embedded in the soil and cannot be removed easily. Labour costs hinders removal of their plastics, thereby leaving them in the soil. They obstruct the root zone activities reducing the agricultural productivity. Being non-biodegradable they remain in the soil for a very long time, thus affecting the farm economy.
• Attracted by food left-over in plastic carry bag in marriage halls, religious places, tourist places large catering houses, cows and other domestic animals eat them. The plastic accumulated in their digestive system, often resulting in their death.

Prevention of Plastic-Disposal – Related Problems

Do not burn the plastics. They are valuable resource. Also gaseous emissions from combustion of plastics pollute the air and some of them are considered to be toxic. Combustion of plastics, particularly in high temperature incinerators produces (Dioxins) and (Furan) as by-products. (Dioxins) are a family of more than 75 different chlorinated hydrocarbons while Plastic or PVC - polyvinyl chloride is a chlorinated hydrocarbon. Some of them are highly toxic and are persistent chemicals that stay in the environment for a very long period. (Furans) (e.g. Furfuran) a colorless liquid, with a low boiling point of  320 °C- used as an intermediate chemical in manufacture of synthetic resins are also toxic in nature.

Recycling

The best way to tackle the plastic-disposal problem is to adopt suitable methods for collection and conveyance of plastic articles and practice recycling. With proper quality control, reprocessed plastics can be made as good as first- generation products are cheaper than good reprocessed plastic goods. Methods should be devised to make up this extra cost through taxes or subsidy. The extra monetary expenses involved in purifying the used plastic may become small compared to the environmental burden imposed by indiscriminate discarding of plastics.

 Should 'Plastics toe banned?   Some environmental activists are arguing in favour of completely banning low-end plastic items and recycled plastics. This is not very sound thinking particularly in India. Thousands of families are dependent on the collection of plastic wastes and small-scale reprocessing. Besides, more area would be deforested to supply raw materials to paper manufacturing industries for producing packing paper and carry bags.

Government Regulations on Manufacture and Use of Recycled Plastics

The Ministry of Environment and Forests issued the Recycled Plastics Manufacture and Usage Rules 1999, and amended it in 2003 under the Environment (Protection) Act, 1986 for regulating and managing plastic carry bags and containers.

Salient features of the Rules are:-

• No vendor shall use carry bags and containers of recycled plastics for storing carrying and or packaging of foodstuffs.
• Carry bags and container used for packaging of foodstuff shall be made of virgin plastic and of natural shade or white.
• Carry bags and container made from recycled plastics must be manufactured using pigments and colorants as per IS: 9833/1981 notified by the Bureau of Indian Standards (BIS);
• Minimum thickness of carry bags made of virgin or recycled plastics must not be less than 20 microns.
• Manufactures of recycled carry bag shall code/ mark carry bags and containers as per IS: 14534: 1998 and mark them as "recycled "along with percentage of recycled material.
• Manufactures shall print on words packet containing carry bags the words "Recycled marital" or "virgin plastics' as the case may be.
• No vendor shall use carry bags made of virgin or recycle plastic below 8 x 12 inches {20 x 30 cm} in size; an 50 bags of such will have minimum weight of 105 grams and proportionate increase in weight to the increased size of the carry bags; for selling any commodity.
• Every occupier manufacturing carry bags or container shall apply in prescribed form to the State Pollution Control Board/Pollution Control Committee for grant of Registration and renewal of Registration.
• The State Pollution Control Board / Pollution Committee shall issue and renew the Registration after ascertaining that the unite meets the norms prescribed under these rules and also possesses a valid cosset under Air and Water Act as per requirements of the State Pollution Control Board / Pollution Control Committee.
• The prescribed authority of enforcement of provisions relating to use, collection, segregation, transpiration and disposal is with District collector, Deputy Commissioner of the concerned district, where no such Authority has been constituted by the State Government/Union Territory administration under any law regarding non- biodegradable garbage
• SPCB's / PCC's are the prescribed authority for enforcement of provisions relating to manufacture and recycling.

Difficulties in Recycling

Almost the entire content of the discarded plastics is made up of thin carry bags and small food-packaging pouches. Laminations made on books, electronic goods, compact discs, cassettes, and many consumer goods add to this problem.

• The tendency of people particularly house wives is to preserve the thick large bags and discard the thin carry bags with the domestic garbage. Once they get mixed up with the garbage these carry bags are difficult to separate. Cost of retrieval becomes more. Even the rag pickers do not find it attractive to collect the carry bags. If housewives, shopkeepers, and other users discard the carry bags in a container for periodic collection by some designated agency for recycling, the problem of plastics in environment can be greatly reduced.

• An alternative to the plastic disposal problem has evolved in the form of 'Bio-degradable plastics'. It is possible to collect these items along with the municipal solid waste (MSW) for suitable disposal.
• MSW collection and disposal is not satisfactory in most of the towns in India. The bio-degradable plastics will add to the already piling up municipal garbage. The immediate benefits of recovery and recycle of normal plastics is also lost if bio-degradable plastics are introduced.
• As of now, compared to normal plastic, the bio-degradable plastics are expensive and the technology for manufacture is not easily available. It may be possible to treat bio-degradable plastics in countries where solid waste management systems are working satisfactorily and

Reuse of Plastics

Mixing shredded PVC bags with asphalt for road making has been experimented with reasonable success. Rope-making using fiber removed from knitted cement bags is done in rural areas. These ropes are used in farming activities.

Mercury Pollution

Mercury is one of the most harmful pollutants faced by fish and wildlife.

• Mercury pollution arises from a variety of sources. is mercury mining although this is overwhelming now only in China and some Central Asian countries such as Kyrgyzstan. It is also very heavily used in artisanal and small-scale gold mining to separate gold from the ore.
• Mercury is used in the chemical and petrochemical industries and also in household products like compact fluorescent lamps (CFLs) and thermometers. Mercury emissions to the atmosphere also take place from coal-fired power plants.
• Mercury is present in industrial effluents that are let into water bodies and the sea and enters the human food chain through the consumption of fish. This is, in fact, what caused the disaster at Minamata in the 1950s. Contaminated sites including old mines, landfills and waste disposal locations are also important sources of mercury pollution.
• India dragged its feet a bit, but in the end signed up to the Minamata Convention on Mercury on 30 September, a year after it was adopted. The Minamata Convention gives India five years to control and, where feasible, to reduce emissions from new power plants and 10 years to do so for existing power plants.
• The Minamata Convention on Mercury is a global treaty to protect human health and the environment from the adverse effects of mercury. It was agreed at the fifth session of the Intergovernmental Negotiating Committee in Geneva, Switzerland at 7 a.m. on the morning of Saturday, 19 January 2013.
• The major highlights of the Minamata Convention on Mercury include a ban on new mercury mines, the phase-out of existing ones, control measures on air emissions, and the international regulation of the informal sector for artisanal and small-scale gold mining.

Degradation of Natural Resources

The degradation of natural resources has occurred not only by pollution but also by improper utilization of natural resources

Soil Erosion and Desertification

The Development of fertile, top soil, takes centuries but the following human - practices can remove or erode this soil easily

• Over-cultivation
• Urbanization
• Deforestation
• Unrestricted grazing
• Poor irrigation

When large barren patches extend and meet over time, a desert is created. Now-a- days the desertification is occurring mainly clause of urbanization, by human activities.

Water-Logging and Soil Salinity

These problems have come-up due to Green revolution. When irrigation is done and there is no proper drainage of water, it leads to water-logging in the soil.

Besides affecting the crops, the water logging draws down salt soil surface. This soil is deposited as a thin crust and also acumulates in the roots of plants. This increased salt content (Soil-salinity) is injurious to the growth of crops and damages agriculture

 Earth Hour   WWF's Earth Hour is an annual global celebration where people switch off their lights for one hour to show they care about the future of our planet. This year?s celebrations will be on Saturday 19 March from 8.30 pm to 9.30 pm. Since it first began in Sydney Australia in 2007, the number of countries taking part in Earth Hour has grown to an incredible 172 countries and territories. India joined the Earth Hour campaign in 2009 and over the years has seen an exponential growth in participation across cities, towns and even far-flung villages of rural India. Iconic monuments of the country like the Rashtrapati Bhawan, Gateway of India, India gate, Howrah Bridge and the Victoria Memorial, among others, swithch off their non-essential lights in support of this global campaign.

Eco Sensitive Zones

• The concept of ecologically sensitive areas is very much an Indian invention, rooted in attempts by civil society to use the Environmental Protection Agency (EPA) to promote sustainable development alongside protection of the natural heritage.
• The term 'Ecologically Fragile Area' was first used in 1991 for Dahanu Taluka in Maharashtra, followed by the declaration of other ESAs like Mahabaleshwar-Panchgani and Matheran.
• These are all initiatives of civil society organisations or are a consequence of a resolution of the Indian Board for Wildlife in 2002 to protect areas up to 10 kilometres from the boundaries of wildlife sanctuaries and national parks.
• Initially, there were no guidelines available on what areas may be considered ecologically sensitive, nor on working out an appropriate management regime. These issues were addressed in 2000 by the Pronab Sen Committee.
• The Sen Committee's foremost criterion for identification of ESA is endemism. Western Ghats harbours well over two thousand endemic species of flowering plants, fish, frogs, birds and mammals amongst the better known groups of organisms, and thousands more amongst less studied groups.
• Amongst themselves these span the entire Western Ghats and all conceivable habitats, including highly disturbed The Western Ghats region also qualifies as an ESA under several other Sen Committee criteria.
• Under ESZ, commercial mining, polluting industries and large hydro-power projects are prohibited as per the ministry guidelines. At present the 29 ESZ notified by the Central government are spread across Haryana, Gujarat, Jharkhand, Kamataka, Sikkim, Goa, Maharasthra, Rajasthan, Gujarat and Uttarakhand.

#### Other Topics

##### Notes - Environmental Issues

You need to login to perform this action.
You will be redirected in 3 sec