Chapter 9 pollution in the world


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Chapter 9 pollution in the world

  1. 1. Chapter 9 Pollution in the WorldPollution o Introduction of substances into the environment such that it results in unpleasant or damaging effects on people, animals, plants and buildings o Greater source of pollution is from human activities o Pollutants are often found in waste which are materials that are useless and no longer wanted o Can lead to other types of pollution  E.g. Air pollution can form acid rain which will cause water pollution when they fall into the river→ the harmful gases mix with the water vapour to form acid rain Air Pollution o Occurs when pollutants such as dust, smoke and toxic gases are released into the environment o When dust and smoke particles suspended in the air, it will form haze o Dust and smoke can combine with water vapour and toxic gases to from smog o Causes of air pollution  Natural Volcanic eruption o Large amount of volcanic ash, smoke and gases are released Forest fire o Occur naturally in times of prolong hot and dry weather o The dust and smoke particles are suspended in the air and may be carried by wind to other places  Human Industries o Release large amount of dust and smoke o When fossil fuel is burned in power station, soot and poisonous like sulphur dioxide are released Motor vehicles o 90% of dust and smoke in the air are emitted by vehicles o The emission also contain harmful gases, such as carbon monoxide and nitrogen oxides Construction work o Clearing of land, construction of buildings and transportation of construction o Extent of air pollution  Health Problems Dust and smoke can cause difficulty in breathing as well as irritation to people’s throats and eyes Prolong exposure will result in respiratory problems such as bronchitis and asthma
  2. 2. Smog can have toxic gas such as carbon monoxide which can cause serious health issues and even death Sulphur dioxide and nitrogen oxides can attack a person’s respiratory system, increasing the risk of developing lung and heart diseases and even cancer  Traffic hazards High amount of dust and smoke make it difficult to see distance object Airport may have to stop all flights → economical loss It is also inconvenient and may be dangerous for driving  Environmental problems Acid rain destroys forests, kills fish in rivers and lakes, as well as corrode buildingsWater Pollution o Occur when pollutants are discharged directly into water bodies o When pollutants on land are blown by wind or washed by rain into water bodies o Cause of water pollution  Improper disposal of sewage → solid or liquid waste produce by household or industries If sewage not treated it will pollute the water body because it contains human waste, detergent and chemicals Some substances such as detergent are non-biodegradable and will remain in the water and cause water pollution  Industrial waste Especially harmful as it usually contains large amount of toxic chemicals Sometimes illegally disposed into river or seas  Oil Spills Occur when the hull of an oil tanker us torn by sharp rocks or collision with another ship Difficult to clean as it spreads over large area and not easily broken down o Extent of water pollution  Endangering plant and animals species The oil will stick to their feather or fur when they come into contact with the polluted water This removes the air trapped by the feather and fur which function as a layer of insulation for the animal causing them to freeze to death in the cold The oil also clog the birds feather, preventing them from flying and floating, causing them to drown Improper disposal of everyday household waste into river → can destroy aquatic life
  3. 3. o The household detergent contains chemical that encourages growth of algae on river surface o This will prevent sunlight from reaching the plants beneath, causing them to die as they cannot photosynthesis o Animals that depend on plant to survive will die too  Negative impact on human health Poisons in industrial waste can accumulate in the bodies of fish and shellfish The poison will pass on to humans when they eat the fishes People will also suffer from cholera and typhoid when they drink water that is contaminated  Economic loss Oil spill threaten fisherman livelihood as well as the fishing industry When the oil spill reaches the tourist resort, it will be unattractive to tourist The oil spills requires huge effort and is very costlyLand Pollution o Occur when waste is not disposed of not properly o When chemical are used excessively on farm o Cause of land pollution  Improper disposal of waste Increase in world population o Causes increase in consumption of good and services → more waste is produced →countries have difficulty finding suitable places to dispose of the waste→ great heaps of rubbish are left in public places or at illegal dumping grounds Improper of waste also occur at mining sites  Excessive use of fertilisers and pesticides Land become polluted when chemical fertilisers and pesticides are washed into the soil As pest develop resistant to pesticide over time, farmers are forced to increase the amount of pesticides used o Extent of land pollution  Negative impact on human health Improper disposal of waste is unhygienic and dangerous to humans Waste attracts pest which carry germs and spread diseased Farmer who are exposed to large amount of pesticides risk developing cancer and liver failure  Poisoning of animals Pesticides kill both pest and useful organisms such as earthworms When birds eat the earthworms, the toxic chemicals are passed on to them, affecting their reproductive system The eggs are thin and break easily → lead to extinction of some bird
  4. 4. Measures Taken to Reduce Pollution o International efforts  Pollutants can be carried by wind or water to the next country, thus be seen as a regional problem  Governments from various countries and international organisations, such as the United Nations Environment Programme(UNEP), need to work together to reduce pollution  Sustainable development is development that meets the needs of present generations without compromising the ability of future generations to meet their own needs  In SEA, Singapore works with Indonesia and Malaysia to help prevent pollution in Malacca and Singapore Straits Implemented a mandatory ship reporting system which requires all ships passing through the Malacca and Singapore Straits to report and provide information on any damages or defects they may have Ships also have to report any pollutants that are released from vessels Authorities from three countries have also been trained to respond quickly to any incidents of oil spills  National Efforts Enforcing laws and regulations o Countreis enforce laws to control amount of pollutants released by industries o Ensure companies treat their waste before disposing them o In Singapore, the National environment Agency (NEA) carries out programme to monitor, reduce and prevent air, water and land pollution o E.g. power stations and vehicles in Singapore have to ensure that the amount of pollutants produced is within safety limits Using alternate sources of energy o “Clean” energy which does not release harmful materials into the environment o E.g. wind energy, hydroelectricity and solar energy Using advanced technology o To treat waste and remove pollutants, reducing impacts of pollution on the environment o E.g. Governments of countries have invested in building sewage treatment plants to treat waste before releasing them into water bodies Developing proper waste disposal methods o Landfills  Huge pits dug in the ground for disposal of solid waste and then covered with soil, leaving them to rot or decompose underground
  5. 5.  Landfills take up lot of space o Incineration  Burning waste at high temperatures  Reduces the volume of waste by 90%  Energy produced can also be converted to electricity  Releases dust particles into the air → air pollution  Some waste like concrete cannot be burnt completely Educating the public o Encourage people and industries to produce less waste o Programme such as campaign and talks inform people about the harmful effects of excessive waste on the environment o Discourages people from pollution o Reduce, reuse and recycle (3Rs) o Individual efforts  Go ‘green’ Switching lights off when they are not in sue → reduce energy Taking public transport → reduce air pollution Buying environmentally friendly or ‘green products’, such as rechargeable batteries with lower mercury content made of recyclable materials → reduce waste produce  Get involved Reusing and recycling waste produce Waste can be reduced if we do not buy or use unnecessary things Think of how an item can be reused before throwing them away Discard recyclable materials into recycling bin Recycling involves making new things out of old materials  Be informed Making an effort to learn more about the environment How to help the environmentEnvironmental Pollution in Singapore o Environmental planning in Singapore  Government has emphasized importance of high standard of environmental cleanliness  Ministry of the Environment and Water Resources (MEWR) set up in 1972 to deliver and sustain a clean and healthy environment National Environment Agency (NEA), responsible for protecting and enhancing Singapore’s clean living environment Also in charge of ensuring a high standard of public health, cleanliness and hygiene MEWR launched the Singapore Green Plan (SGP) in 1992 to lay outSingapore’searly environmental aims, later revised in 2002  Key environmental protection efforts Clean land
  6. 6. Clean air Clean water Building partnerships