LESSON 12: DIMENSIONS OF POLLUTION CONTROL
UNIT II BUSINESS AND ITS EXTERNAL EXCHANGES CHAPTER 3: ETHICS AND THE ENVIRONMENT
The moment you step out of the house and are on the road you can actually see the air getting polluted; a cloud of smoke from the exhaust of a bus, car, or a scooter; smoke billowing from a factory chimney, fly ash generated by thermal power plants, and speeding cars causing dust to rise from the roads. Natural phenomena such as the eruption of a volcano and even someone smoking a cigarette can also cause air pollution.
Dear students, today we will talk about ethical perspectives on environmental pollution.
Points to be covered in this lesson:
Concept of environmental ethics Pollution and its impacts
A study of conceptual and moral issues concerning the growth of human population, consumption of resources, animal rights, the moral status of nature and species, etc. Some Issues in Environmental Ethics
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Why should we care about the planet? Or about its nonhuman residents? Do we have any obligations to future generations? Who, or what, are the proper subjects of moral considerations? Do animals have any serious moral standing? Do they have moral rights? Can we use animals and nature in any way that suits us? On what foundations should we rest our concern for rain forest, marine ecology, or natural landscapes? Gaseous Composition of Unpolluted Air Gases Nitrogen Oxygen Water Argon Carbon Dioxide Neon Helium Methane Krypton Nitrous oxide Hydrogen Xenon Organic vapours Parts per million (vol.) 756,500 202,900 31,200 9,000 305 17.4 5.0 0.97-1.16 0.97 0.49 0.49 0.08 ca.0.02
Two kinds of Environmental Strategies • Morally-Indirect Environmental Strategies:
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We ought to protect the natural environment because, in the long run, it is good for us. We ought to protect the natural environment because it is good for natural environment Or something which is part of natural environment The nature contains something that is intrinsically good The natural environment itself, or some objects in it, or some features of these objects, are intrinsically good)
Morally-Direct Environmental Strategies:
What is Air Pollution?
Air pollution is aggravated because of four developments: increasing traffic, growing cities, rapid economic development, and industrialization. The Industrial Revolution in Europe in the 19th century saw the beginning of air pollution as we know it today, which has gradually become a global problem.
I’ll go out for a breath of fresh air’ is an often-heard phrase. But how many of us realize that this has become irrelevant in today’s world, because the quality of air in our cities is anything but fresh.
Air and its Major Pollutants One of the formal definitions of air pollution is as follows – ‘The presence of one or more contaminants in the atmosphere in such quality and for such duration as is injurious, or tends to be injurious, to human health or welfare, animal or plant life.’ It is the contamination of air by the discharge of harmful substances. Air pollution can cause health problems and it can also damage the environment and property. It has caused thinning of the protective ozone layer of the atmosphere, which is leading to climate change. Modernization and progress have led to air getting more and more polluted over the years. Industries, vehicles, increase in the population, and urbanization are some of the major factors responsible for air pollution. The following industries are among those that emit a great deal of pollutants into the air: thermal power plants, cement, steel, refineries, petro chemicals, and mines. Air pollution results from a variety of causes, not all of which are within human control. Dust storms in desert areas and smoke from forest fires and grass fires contribute to chemical and particulate pollution of the air. The source of pollution may be in one country but the impact of pollution may be felt elsewhere. The discovery of pesticides in Antarctica, where they have never been used, suggests the extent to which aerial transport can carry pollutants from one place to another. Probably the most important natural source of air pollution is volcanic activity, which at times pours great amounts of ash and toxic fumes into the atmosphere. The eruptions of such volcanoes as Krakatoa in Indonesia, Mt. St. Helens in Washing- ton, USA and Katmai in Alaska, USA, have been related to measurable climatic changes. National Ambient Air Quality Standards
The Major Air Pollutants and their Sources Carbon monoxide (CO) is a colorless, odorless gas that is produced by the incomplete burning of carbon-based fuels including petrol, diesel, and wood. It is also produced from the combustion of natural and synthetic products such as cigarettes. It lowers the amount of oxygen that enters our blood. It can slow our reflexes and make us confused and sleepy. Carbon dioxide (CO2) is the principle greenhouse gas emitted as a result of human activities such as the burning of coal, oil, and natural gases. Chlorofluorocarbons (CFC) are gases that are released mainly from air-conditioning systems and refrigeration. When released into the air, CFCs rise to the stratosphere, where they come in contact with few other gases, which lead to a reduction of the ozone layer that protects the earth from the harmful ultraviolet rays of the sun. Lead is present in petrol, diesel, lead batteries, paints, hair dye products, etc. Lead affects children in particular. It can cause nervous system damage and digestive problems and, in some cases, cause cancer. Ozone occurs naturally in the upper layers of the atmosphere. This important gas shields the earth from the harmful ultraviolet rays of the sun. However, at the ground level, it is a pollutant with highly toxic effects. Vehicles and industries are the major source of ground-level ozone emissions. Ozone makes our eyes itch, burn, and water. It lowers our resistance to colds and pneumonia. Nitrogen oxide (Nox) causes smog and acid rain. It is produced from burning fuels including petrol, diesel, and coal. Nitrogen oxides can make children susceptible to respiratory diseases in winters. CONCENTRATION 60 µg/m3 80 µg/m3 60 µg /m3 80 µg /m3 140 µg/m3 200 µg/m3 0.75 µg/m 3 1.0 µg/m3 2.0 µg/m3 4.0 µg/m3 60 µg/m3 100 µg/m3 Suspended particulate matter (SPM) consists of solids in the air in the form of smoke, dust, and vapor that can remain suspended for extended periods and is also the main source of haze which reduces visibility. The finer of these particles, when breathed in can lodge in our lungs and cause lung damage and respiratory problems. Sulphur dioxide (SO2) is a gas produced from burning coal, mainly in thermal power plants. Some industrial processes, such as production of paper and smelting of metals, produce Sulphur dioxide. It is a major contributor to smog and acid rain. Sulfur dioxide can lead to lung diseases.
POLLUTANT Sulphur dioxide (SO2)
AVERAGE TIME Annual average 24 hour
Oxides of nitrogen (NO2)
Annual average 24 hour
Suspended Particulate Matter (SPM)
Annual average 24 hour
Lead Carbon monoxide
Annual average 24 hour Annual average 24 hour
Respirable Particulate Matter (RPM)
Annual average 24 hour
the production of natural vitamin D leading to a rise in the cases of rickets. Smog causes a misty haze similar to fog, but very different in composition. In fact the word smog has been coined from a combination of the words fog and smoke. Smog refers to hazy air that causes difficult breathing conditions. The most harmful components of smog are ground-level ozone and fine airborne particles. Ground-level ozone forms when pollutants released from gasoline and diesel-powered vehicles and oil-based solvents react with heat and sunlight. It is harmful to humans, animals, and plants.
Another effect of air pollution is acid rain. The phenomenon occurs when sulphur dioxide and nitrogen oxides from the burning of fossil fuels such as, petrol, diesel, and coal combine with water vapor in the atmosphere and fall as rain, snow or fog. These gases can also be emitted from natural sources like volcanoes. Acid rain causes extensive damage to water, forest, soil resources and even human health. Many lakes and streams have been contaminated and this has led to the disappearance of some species of fish in Europe, USA and Canada as also extensive damage to forests and other forms of life. It is said that it can corrode buildings and be hazardous to human health. Because the contaminants are carried long distances, the sources of acid rain are difficult to pinpoint and hence difficult to control. For example, the acid rain that may have damaged some forest in Canada could have originated in the industrial areas of USA. In fact, this has created disagreements between Canada and the United States and among European countries over the causes of and solutions to the problem of acid rain. The international scope of the problem has led to the signing of international agreements on the limitation of sulphur and nitrogen oxide emissions. Smog
The industrial revolution in the 19th century saw the beginning of air pollution in Europe on a large scale and the presence of smog mainly in Britain. The industries and the households relied heavily on coal for heating and cooking. Due to the burning of coal for heat during the winter months, emissions of smoke and Sulphur dioxide were much greater in urban areas than they were during the summer months. Smoke particles trapped in the fog gave it a yellow/black color and this smog often settled over cities for many days. The effects of smog on human health were evident, particularly when smog persisted for several days. Many people suffered respiratory problems and increased deaths were recorded, notably those relating to bronchial causes. A haze of dense harmful smog would often cover the city of London. The first smog-related deaths were recorded in London in 1873, when it killed 500 people. In 1880, the toll was 2000. London had one of its worst experiences with smog in December 1892. It lasted for three days and resulted in about 1000 deaths. London became quite notorious for its smog. By the end of the 19th century, many people visited London to see the fog. Despite gradual improvements in air quality during the 20th century, another major smog occurred in London in December 1952. The Great London Smog lasted for five days and resulted in about 4000 more deaths than usual. In response to the Great London Smog, the government passed its first Clean Air Act in 1956, which aimed to control domestic sources of smoke pollution by introducing smokeless zones. In addition, the introduction of cleaner coals led to a reduction in sulphur dioxide pollution. In the 1940s, severe smog began covering the city of Los Angeles in the USA. Relatively little was done to control any type of pollution or to promote environmental protection until the middle of the 20th century. Today, smoke and sulphur dioxide pollution in cities is much lower than in the past, as a result of legislation to control pollution emissions and cleaner emission technology. Major Air Pollutants and Associated Health Hazards
Pollutant RSPM SO2 NO2 SPM Benzene Ozone CO Lead Health Impacts Respiratory illness, including chronic bronchitis and asthma; heart diseases Heart diseases, respiratory problems including pulmonary emphysema; cancer, eye burning, headache etc. Lung irritation, viral infection, chest tightness etc. Pneumoconiosis, restrictive lung diseases etc. Immunotoxicity, asthma, anemia etc. Impaired lung function, chest pain, coughing etc. Cherry lips, unconsciousness, asphyxiation etc. Decreased hemoglobin synthesis, anemia etc.
The term smog was first used in 1905 by Dr H A Des Voeux to describe the conditions of fog that had soot or smoke in it. Smog is a combination of various gases with water vapor and dust. A large part of the gases that form smog is produced when fuels are burnt. Smog forms when heat and sunlight react with these gases and fine particles in the air. Smog can affect outlying suburbs and rural areas as well as big cities. Its occurrences are often linked to heavy traffic, high temperatures, and calm winds. During the winter, wind speeds are low and cause the smoke and fog to stagnate; hence pollution levels can increase near ground level. This keeps the pollution close to the ground, right where people are breathing. It hampers visibility and harms the environment. Heavy smog is greatly decreases ultraviolet radiation. In fact, in the early part of the 20th century, heavy smog in some parts of Europe resulted in a decrease in
Water Pollution When toxic substances enter lakes, streams, rivers, oceans, and other water bodies, they get dissolved or lie suspended in water or get deposited on the bed. This results in the pollution of water whereby the quality of the water deteriorates, affecting aquatic ecosystems. Pollutants can also seep down and affect the groundwater deposits. Water pollution has many sources. The most polluting of them are the city sewage and industrial waste discharged into the rivers. The facilities to treat wastewater are not adequate in any city in India. Presently, only about 10% of the wastewater generated is treated; the rest is discharged as it is into our water bodies. Due to this, pollutants enter groundwater, rivers, and other water bodies. Such water, which ultimately ends up in our households, is often highly contaminated and carries disease- causing microbes. Agricultural run-off, or the water from the fields that drains into rivers, is another major water pollutant as it contains fertilizers and pesticides. Domestic sewage refers to wastewater that is discarded from households. Also referred to as sanitary sewage, such water contains a wide variety of dissolved and suspended impurities. It amounts to a very small fraction of the sewage by weight. But it is large by volume and contains impurities such as organic materials and plant nutrients that tend to rot. The main organic materials are food and vegetable waste, plant nutrient come from chemical soaps, washing powders, etc. Domestic sewage is also very likely to contain disease-causing microbes. Thus, disposal of domestic waste water is a significant technical problem. Sewage generated from the urban areas in India has multiplied manifold since 1947. Today, many people dump their garbage into streams, lakes, rivers, and seas, thus making water bodies the final resting place of cans, bottles, plastics, and other household products. The various substances that we use for keeping our houses clean add to water pollution as they contain harmful chemicals. In the past, people mostly used soaps made from animal and vegetable fat for all types of washing. But most of today’s cleaning products are synthetic detergents and come from the petrochemical industry. Most detergents and washing powders contain phosphates, which are used to soften the water among other things. These and other chemicals contained in washing powders affect the health of all forms of life in the water. Agricultural Run-off The use of land for agriculture and the practices followed in cultivation greatly affect the quality of groundwater. Intensive cultivation of crops causes chemicals from fertilizers (e.g. nitrate) and pesticides to seep into the groundwater, a process com- monly known as leaching. Routine applications of fertilizers and pesticides for agriculture and indiscriminate disposal of industrial and domestic wastes are increasingly being recognized as significant sources of water pollution. The high nitrate content in groundwater is mainly from irrigation run-off from agricultural fields where chemical fertilizers have been used indiscriminately.
Industrial Effluents Waste water from manufacturing or chemical processes in industries contributes to water pollution. Industrial waste water usually contains specific and readily identifiable chemical compounds. During the last fifty years, the number of industries in India has grown rapidly. But water pollution is concentrated within a few subsectors, mainly in the form of toxic wastes and organic pollutants. Out of this a large portion can be traced to the processing of industrial chemicals and to the food products industry. In fact, a number of large- and medium-sized industries in the region covered by the Ganga Action Plan do not have adequate effluent treatment facilities. Most of these defaulting industries are sugar mills, distilleries, leather processing industries, and thermal power stations. Most major industries have treatment facilities for industrial effluents. But this is not the case with small-scale industries, which cannot afford enormous investments in pollution control equipment as their profit margin is very slender. Effects of Water Pollution The effects of water pollution are not only devastating to people but also to animals, fish, and birds. Polluted water is unsuitable for drinking, recreation, agriculture, and industry. It diminishes the aesthetic quality of lakes and rivers. More seriously, contaminated water destroys aquatic life and reduces its reproductive ability. Eventually, it is a hazard to human health. Nobody can escape the effects of water pollution. The individual and the community can help minimize water pollution. By simple housekeeping and management practices the amount of waste generated can be minimized. Oil Spills
Among the most dangerous of all water pollutants is fuel oil. Oil spills from tankers at sea or leaks from underground storage tanks on land are very difficult to control as oil tends to spread very fast, affecting a large area in a very short time. They are a major menace to the environment as they cause severe damage to surrounding ecosystems. Oil spills at sea decrease the oxygen level in the water and cause grave harm to the creatures living in the sea. Since crude oil is lighter than water, it floats on the surface and poses the threat of swift-spreading fire. Oil spills are rather common as oil tankers can meet with accidents either in deep sea or offshore, while waiting to be loaded or unloaded. During the Gulf War, several oil reservoirs were destroyed at sea and the effect on marine life was devastating. Seabirds and fish were washed ashore, their bodies covered with oil. On land crude is transported through pipelines or tankers which can get damaged and spew out crude oil over the land, thereby
contaminating it. Bioremediation is a method that is now being use to put a check to the damage done by this oil spill. Health Impacts of Water Pollution It is a well-known fact that clean water is absolutely essential for healthy living. Adequate supply of fresh and clean drinking water is a basic need for all human beings on the earth, yet it has been observed that millions of people worldwide are deprived of this. Freshwater resources all over the world are threatened not only by over exploitation and poor management but also by ecological degradation. The main source of freshwater pollution can be attributed to discharge of untreated waste, dumping of industrial effluent, and run-off from agricultural fields. Industrial growth, urbanization and the increasing use of synthetic organic substances have serious and adverse impacts on freshwater bodies. It is a generally accepted fact that the developed countries suffer from problems of chemical dis- charge into the water sources mainly groundwater, while developing countries face problems of agricultural run-off in water sources. Polluted water like chemicals in drinking water causes problem to health and leads to waterborne diseases which can be prevented by taking measures can be taken even at the household level. Groundwater and its Contamination
Ground water can be contaminated through various sources and some of these are mentioned below. Pesticides. Run-off from farms, backyards, and golf courses contain pesticides such as DDT that in turn contaminate the water. Its effects on the ecosystems and health are endocrine and reproductive damage in wildlife. Groundwater is susceptible to contamination, as pesticides are mobile in the soil. It is a matter of concern as these chemicals are persistent in the soil and water. Sewage. Untreated or inadequately treated municipal sewage is a major source of groundwater and surface water pollution in the developing countries. The organic material that is discharged with municipal waste into the watercourses uses substantial oxygen for biological degradation thereby upsetting the ecological balance of rivers and lakes. Sewage also carries microbial pathogens that are the cause of the spread of disease. Nutrients. Domestic waste water, agricultural run-off, and industrial effluents contain phosphorus and nitrogen, fertilizer run-off, manure from livestock operations, which increase the level of nutrients in water bodies and can cause eutrophication in the lakes and rivers and continue on to the coastal areas. The nitrates come mainly from the fertilizer that is added to the fields. Excessive use of fertilizers cause nitrate contamination of groundwater, with the result that nitrate levels in drinking water is far above the safety levels recommended. Good agricultural practices can help in reducing the amount of nitrates in the soil and thereby lower its content in the water. Synthetic Organics. Many of the 100 000 synthetic compounds in use today are found in the aquatic environment and accumulate in the food chain. POPs or Persistent organic pollutants represent the most harmful element for the ecosystem and for human health, for example, industrial chemicals and agricultural pesticides. These chemicals can accumulate in fish and cause serious damage to human health. Where pesticides are used on a large-scale, groundwater gets contami- nated and this leads to the chemical contamination of drinking water. Acidification. Acidification of surface water, mainly lakes and reservoirs, is one of the major environmental impacts of transport over long distance of air pollutants such as sulphur dioxide from power plants, other heavy industry such as steel plants, and motor vehicles. This problem is more severe in the US and in parts of Europe. Chemicals in Drinking Water Chemicals in water can be either naturally occurring or introduced by human interference and can have serious health effects. Fluoride. Fluoride in the water is essential for protection against dental caries and weakening of the bones, but higher levels can have an adverse effect on health. In India, high fluoride content is found naturally in the waters in Rajasthan. Arsenic. Arsenic occurs naturally or is possibly aggravated by over powering aquifers and by phosphorus from fertilizers. High concentrations of arsenic in water can have an adverse effect on health. A few years back, high concentrations of this element was found in drinking water in six districts in West Bengal. A majority of people in the area was found suffering from arsenic skin lesions. It was felt that arsenic contamination
Many areas of groundwater and surface water are now contaminated with heavy metals, POPs (persistent organic pollutants), and nutrients that have an adverse affect on health. Water-borne diseases and water-caused health problems are mostly due to inadequate and incompetent management of water resources. Safe water for all can only be assured when access, sustainability, and equity can be guaranteed. Access can be defined as the number of people who are guaranteed safe drinking water and sufficient quantities of it. There has to be an effort to sustain it, and there has to be a fair and equal distribution of water to all segments of the society. Urban areas generally have a higher coverage of safe water than the rural areas. Even within an area there is variation: areas that can pay for the services have access to safe water whereas areas that cannot pay for the services have to make do with water from hand pumps and other sources. In the urban areas water gets contaminated in many different ways, some of the most common reasons being leaky water pipe joints in areas where the water pipe and sewage line pass close together. Sometimes the water gets polluted at source due to various reasons and mainly due to inflow of sewage into the source.
in the groundwater was due to natural causes. The government is trying to provide an alternative drinking water source and a method through which the arsenic content from water can be removed. Lead. Pipes, fittings, solder, and the service connections of some household plumbing systems contain lead that contami- nates the drinking water source. Recreational use of water. Untreated sewage, industrial effluents, and agricultural waste are often discharged into the water bodies such as the lakes, coastal areas and rivers endangering their use for recreational purposes such as swimming and canoeing. Petrochemicals. Petrochemicals contaminate the groundwater from underground petroleum storage tanks. Other heavy metals. These contaminants come from mining waste and tailings, landfills, or hazardous waste dumps. Chlorinated solvents. Metal and plastic effluents, fabric cleaning, electronic and aircraft manufacturing are often discharged and contaminate groundwater. Disease Water-borne diseases are infectious diseases spread primarily through contaminated water. Though these diseases are spread either directly or through flies or filth, water is the chief medium for spread of these diseases and hence they are termed as waterborne diseases. Cause Bacterial infections Viral infections Protozoal infections Water-borne disease Typhoid, Cholera, Paratyphoid Fever, Bacillary Dysentry Jaundice, Poliomyelitis Amoebic Dysentry
Fluoride. Excess fluorides can cause yellowing of the teeth and damage to the spinal cord and other crippling diseases. Nitrates. Drinking water that gets contaminated with nitrates can prove fatal especially to infants that drink formula milk as it restricts the amount of oxygen that reaches the brain causing the ‘blue baby’ syndrome. It is also linked to digestive tract cancers. It causes algae to bloom resulting in eutrophication in surface water. Petrochemicals. Benzene and other petrochemicals can cause cancer even at low exposure levels. Chlorinated solvents. These are linked to reproduction disorders and to some cancers. Arsenic. Arsenic poisoning through water can cause liver and nervous system damage, vascular diseases and also skin cancer. Other heavy metals. –Heavy metals cause damage to the nervous system and the kidney, and other metabolic disruptions. Salts. It makes the fresh water unusable for drinking and irrigation purposes. Exposure to polluted water can cause diarrhoea, skin irritation, respiratory problems, and other diseases, depending on the pollutant that is in the water body. Stagnant water and other untreated water provide a habitat for the mosquito and a host of other parasites and insects that cause a large number of diseases especially in the tropical regions. Among these, malaria is undoubtedly the most widely distributed and causes most damage to human health. Toxic Substances Hazardous or toxic substances are substances that can cause an increase in mortality rates or an increase in irreversible or incapacitating illness, or that have other seriously adverse health or environmental effects. These include acidic chemicals, inorganic metals (such as mercury or arsenic), flammable solvents’, pesticides, herbicides, phenols, explosives, and so on. (Radioactive wastes are also classified as hazardous substances, but these will be discussed separately later.) Silvex and 2, 4, 5- T, for example, are two widely used herbicides that contain dioxin-a deadly poison (one hundred times more deadly than strychnine) and a carcinogen. Until 1979 these herbicides were being sprayed on forests in Oregon where they are believed to have led to an ab-normal number of miscarriages in local women and to have caused a range of reproductive defects in animals. A second example: In the late 1970s, toxic chemicals buried by Hooker Chemical Company at sites near Niagara Falls. New York, were found to have leaked from the sites and to have contaminated the surrounding residential are as, including homes, schools, playing fields, and underground water supplies. The chemicals included dioxin, pesticides, carbon tetrachloride, and other carcinogenic or toxic chemicals that were suspected of having induced spontaneous abortions, nerve damage, and congenital malformations among families living nearby. The government estimates that over 58,000 different chemical compounds are currently being used in the United States and that their number is growing each year. Ten times more chemicals, many of them toxic, were being used in the mid11.292
Most intestinal (enteric) diseases are infectious and are transmitted through faecal waste. Pathogens – which include virus, bacteria, protozoa, and parasitic worms – are disease-producing agents found in the faeces of infected persons. These diseases are more prevalent in areas with poor sanitary conditions. These pathogens travel through water sources and interfuses directly through persons handling food and water. Since these diseases are highly infectious, people looking after an infected patient should maintain extreme care and hygiene. Hepatitis, cholera, dysentery, and typhoid are the more common water-borne diseases that affect large populations in the tropical regions. A large number of chemicals that either exist naturally in the land or are added due to human activity dissolve in the water, thereby contaminating it and leading to various diseases. Pesticides. The organophosphates and the carbonates present in pesticides affect and damage the nervous system and can cause cancer. Some of the pesticides contain carcinogens that exceed recommended levels. They contain chlorides that cause reproductive and endocrinal damage. Lead. Lead is hazardous to health as it accumulates in the body and affects the central nervous system. Children and pregnant women are most at risk.
1980s than in 1970. Among the most common of the toxic chemicals produced by industry is acrylonitrile, which is used in the manufacture of plas-tics (used in appliances, luggage, telephones, and numerous common household and industrial products) and whose production is currently rising by 3 percent a year. Acrylonitrile is a suspected carcinogen and it releases the toxic chemi-cal hydrogen cyanide when _plastic containing it is bumed. Benzene is another common industrial toxic chemical used in plastics, dyes, nylon, food additives, detergents., drugs, Fungicides and gasoline. Benzene is a cause of anemia, bone marrow damage, and leukemia. Recent stud-ies have shown that benzene workers are several times more likely than the general population to get leukemia. Vinyl chloride is another common industrial chemical used in the produc-tion of plastics, whose production is rising by 3, percent per year. Vinyl chloride, which is released in small amounts when plastic products deteriorate, causes liver damage, birth anomalies, liver, respiratory, brain, and ‘lymph cancers, and bone damage Phthalates are resins used in industry to produce model cement, paints and finishes. They damage the central nervous system of humans and are toxic to fish and bird life’ Although the health effects of some substances are now known, the tox-icity of many others is unknown and difficult to determine. Many chemicals cause chronic diseases only after a long period following a person’s first exposure to the chemical. For example, most human cancers caused by exposure to toxic chemicals take 15 to 30 years to show up, which makes it difficult to identify the original causes of the disease. Solid Waste The sight of a dustbin overflowing and the stench rising from it, the all too familiar sights and smells of a crowded city. You look away from it and hold your nose as you cross it. Have you ever thought that you also have a role to play in the creation of this stench? That you can also play a role in the lessening of this smell and making this waste bin look a little more attractive if you follow proper methods of disposal of the waste generated in the house?
There are different types of solid waste depending on their source. In today’s polluted world, learning the correct methods of handling the waste generated has become essential. Segregation is an important method of handling municipal solid waste. Segregation at source can be understood clearly by schematic representation. One of the important methods of managing and treating wastes is composting. As the cities are growing in size and in problems such as the generation of plastic waste, various municipal waste treatment and disposal methods are now being used to try and resolve these problems. One common sight in all cities is the rag picker who plays an important role in the segregation of this waste. Garbage generated in households can be recycled and reused to prevent creation of waste at source and reducing amount of waste thrown into the community dustbins. Depletion of Species It is well known that human beings have depleted dozens of plant and animal species to the point of extinction. Since 1600 A.D, at least thirty-six major identifiable species of mammals and ninety-four major identifiable species of birds are known to have become extinct. Several hundred more species, such, as whales and salmon, today find themselves threatened by commercial predators. Forests are also being decimated by the timber industry. Between the years 1600 and 1900 half of .the forested’ land area in the United States was cleared.56 Experts estimate that the planet’s rain forests. are being destroyed at the rate of about 1 percent a year.57 If present trends con-tinue, total forest_ cover will decrease by 40 percent by the end of toe century. The loss of forest habitats -combined with the effects of pollution is expected to lead to _the possible’ extinction of between half a million to two million species-IS to 20 percent of all species on earth-by the beginning of the next century. Depletion of Fossil Fuels Over the last decade the non-conventional and renewable energy sources have been occupying the central place in the area of energy generation and supply due to fast depletion of fossil fuels. According to reports, the conventional energy sources would likely to be exhausted globally by 2050. With such a deadline looming over the head, the technological experts are busy finding viable means of sustaining the existing and discovering new sources of energy. As many researchers argue, however, our consumption of fossil fuels could not continue rising at historical exponential rates As reserves of any resource shrink, they become increasingly difficult, and therefore more costly to extract. Consequently although the rates at which reserves are depleted may rise exponentially for a period, the rising costs of extraction eventually cause the rates to peak and then begin to decline, without complete depletion ever being attained.
Since the beginning, humankind has been generating waste, be it the bones and other parts of animals they slaughter for their food or the wood they cut to make their carts. With the progress of civilization, the waste generated became of a more complex nature. At the end of the 19th century the industrial revolution saw the rise of the world of consumers. Not only did the air get more and more polluted but the earth itself became more polluted with the generation of non biodegrad- able solid waste. The increase in population and urbanization was also largely responsible for the increase in solid waste. Each household generates garbage or waste day in and day out. Items that we no longer need or do not have any further use for fall in the category of waste, and we tend to throw them away.
Environmental ethics is the study of conceptual and moral issues concerning the growth of human population, consumption of resources, animal rights, the moral status of nature and species, etc. Pollution can seriously damage health and environment. Resources are finite.
What is environmental ethics? What are the issues related to environmental ethics? What are the two kinds of environmental strategies?
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