Bio Pw

Pollution is defined as undesirable change in the chemical, physical or biological characteristics of the natural environment caused by pollutants. Pollutants means, any substance that is present in an excessive amount in the environment as a result of human activities. They can be toxic such as pesticides or natural constituents such as carbon dioxide. They bring negative impact towards soil, rivers, seas and even the atmosphere. Four main types of pollution are; a) b) c) d)

air pollution water pollution thermal pollution noise pollution

Let us briefly go through all of these encumbrances. 1. Air Pollution -Smoke, dirt, dust and poisonous gases that are released into the air endangering many living organisms. Most of the air pollutants come from the burning of fossil fuels from motor vehicles. -Let us see, some of the air pollutants that harm our atmosphere.

Pollutants Carbon monoxide

Sources -combustion of fossil fuels -combustion sources such as motor vehicle exhaust, smoke from fires and engine fumes

Carbon dioxide

Combustion of fossil fuels

Effects -combing with haemoglobin to form carboxyhaemoglobin which reduces the capability pf transportation of oxygen by red blood cells. -nausea, headaches, fatigue, brain damage and can be fatal -causing emphysema -affects respiration -causing acid rains which damage buildings

Nitrogen monoxide and nitrogen dioxide

-combustion of fossil fuels

-give arise to greenhouse effect and global warming. -damage lung tissues

-motor vehicle exhaust

-cause bronchitis -irritates the eyes -reduce body’s defence against flu -contributes to acid rains which reduce pH of soil, lakes and rivers. -acid rain can also corrode buildings.

Sulphur dioxide -a pungent gas and acidic -can dissolve in water.

-combustion of fossil fuels -industries

-irritates and damages the lining of the eyes, air passages and lungs. -Causes coughing and wheezing. -acid rain formation can cause skin disease.

-reduce plants’ growth -acid rain, corrodes iron, copper, steel, stonework, destroy buildings. Fine Matter -like smoke fumes, dust, ash pollen.

-combustion of fossil fuels from motor vehicles, agricultural burning and industries. -forest fires. -quarries and asbestos factories.

Lead

-combustion of fossil fuels

-irritates eyes and respiratory tract -haze formation; causing asthma, sore throat and reduce visibility. -darkens vegetations -blocks stomata, thus lowering rate of photosynthesis. -reduces sensitivity of hands and feet coordination -retards mental development in children.

Hydrocarbon

-combustion of fossil fuels from motor vehicles.

-disturbs body’s ability to produce new cells. -affects growth -causes cancer

Air Pollution Index (API) -used to measure air quality. -in Malaysia, air pollutants included ozone, carbon monoxide, nitrogen dioxide, sulphur dioxide and particulate matter. -the index is calculated using the concentrations of major air pollutants. -It is developed in easily understood ranges of values. -Precaution steps must be taken when it exceeds 200. API 0-50

STATUS Good

51-100

Moderate

101-200

Unhealthy

201-300

Very unhealthy

301-500

Hazardous

Above 500

Emergency

LEVEL OF POLLUTION Low, no ill effects on health Moderate pollution, no ill effects on health. Mild aggravation of symptoms among high risk groups. Significant aggravation of symptoms and decrease exercise tolerance among high risk groups. Severe aggravation of symptoms and danger to health. Severe aggravation of symptoms and danger to health.

2. WATER POLLUTION -Discharging of agricultural wastes, industrial wastes, domestic wastes and sewages pollute water sources and lands. -Sources and pollutants of water pollution a) Fertilisers and pesticides from farms -nitrates -phosphates -pesticides -herbicides b) Oil spills -grease -oil c) Sewage effluent -detergent -faeces -nitrates d) Non-biodegradable rubbish -suspended solids -rubbish -oil e) Effluent from factories -heavy metals -oil -grease -chemicals

Effects of Water Pollution 1. HUMAN HEALTH -untreated water contains pathogens like vibrio which causes cholera. -pesticides and herbicides passed to humans via food chain are harmful. -heavy metals such as mercury cause nervous disorders, blindness, and death. 2. ANIMALS & PLANTS -excess nitrates and phosphates lead to eutrophication -rubbish and oil deduce the light penetration and diffusion of oxygen into water, killing aquatic organisms. -oil covers the gills of fishes causing delicacy of respiration among fishes. -decomposition of decayed materials by saprophytic bacteria reduces the oxygen content in the water.

What is eutrophication?? 1. Eutrophication is a natural process whereby an aquatic ecosystem becomes enriched with nutrients, thus causing an excessive growth of aquatic plants. 2. These nutrients come from various sources, like: a) fertilisers (nitrates & phosphates) from agricultural fields. b) Sewage treatment plant discharges c) Run-off of animal wastes. 2. The increases nutrients promote rapid growth of algae when they are deposited into the water sources. 3. Excessive growth of algae is defined as Algal Bloom. 4. Algal Bloom threats the ecosystem in two main ways.

ALGAL BLOOM THREATS THE ECOSYSTEM BY:

1st WAY 1. Densely populated algae cover the water surface and block penetration of sunlight. Thus, no photosynthesis occurs, aquatic plants die. Aquatic animals lose their food sources and habitats. Hence, food chains and ecosystem change. The level of dissolved oxygen in the water also reduced.

2ND WAY 1. When algae die, decomposing organisms especially saprophytic bacteria use up oxygen for its activities. As a result, oxygen content in the water is reduced.

5. Depletion of oxygen results in an increase in biochemical oxygen demand (BOD) 6. Eutrophication increases the BOD value in the water. 7. What is BOD by the way? BOD refers to the amount of oxygen utilized by microorganisms to oxidise all organic matter in one litre of water. 8. The higher the BOD value, the more polluted the water as the dissolved oxygen level decreases.

CORRECT SEQUENCE OF EUTROPHICATION

Nutrients from fertilisers flow into the bodies of water.

Growth of algae increases.

BOD Level increases.

Water surface covered with algae

Aerobic bacteria use up oxygen

3. Thermal Pollution - Thermal pollution happens when there is an increase in the temperature of a water source or excessive heat in the environment. - Hot water is discharged into nearby water sources from the effluent of industrial processes, cooling towers of power stations and reactor plants. - The discharge of hot water increases the water temperature by 10 degree Celsius. - Reflection of heat from glass buildings also make the world succumbs to a high rises in temperature of the surroundings. -Effects of an increase n water temperature: 1) The level of dissolved oxygen in water reduced. This affects the life of aerobic aquatic organisms. 2) It causes the death of some aquatic organisms because several organisms can only thrive at certain temperatures. Some organisms might also move away, hence disrupts the food chain in an ecosystem. 3) Rapid growth of algae encouraged. Lead to a higher BOD value.

4. Noise Pollution - Noise pollution occurs when there are disruptions by high decibels of noises. - Undeniable, urban developments cause most of the noise pollution we are confronted with now. Examples are: a) b) c) d)

vehicles construction sites machines in industrial fields entertainment outlets

- The World Health Organisation (WHO) recommends a noise level of not exceeding than 55 decibels (Db). -Long exposure to a noise level of 80 Db may cause headache, emotional and mental disturbances and may also lead to deafness.

1. GREENHOUSE EFFECT - Sun’s rays reach the Earth through radiation. Some of these radiations are absorbed by the Earth to warm the surfaces of sea and lands. - As the Earth is warmed, heat in the form of infrared radiation is radiated back into space. - However, much of this radiation is prevented from escaping into space by greenhouse gases like carbon dioxide, methane, nitrous oxide and chlorofluorocarbons - So, the infrared radiation is radiated back to the Earth’s surfaces and warming the Earth further. - This phenomenon is referred as the greenhouse effect, which is similarly to the greenhouse used in farming in countries which experience temperature climates. In the original greenhouse, the glass of the greenhouse allows light to enter but prevents the loss of heat. The kept heat is being used to warm the soil and air. - As usual, human activities are the main contributors toward greenhouse effect, mainly burning of fossil fuels and deforestation. - The increment of greenhouse gases increases the greenhouse effect causing more heat trapped in the atmosphere. The Earth’s average temperature increases and is known as GLOBAL WARMING. - GLOBAL WARMING’S drawbacks are like stated below: ~ melting of polar ice and glaciers causing rise in sea level ~ floods in low-lying countries ~ change in weather patterns ~ increase in droughts ~ decrease in crops yield due to infertile soil ~ spread of pest and disease-carrying vectors to new areas ~ Intense rains in some regions

STEPS TO REDUCE GLOBAL WARMING ~ reduce burning of fossil fuels ~ reduce deforestations ~ stop open burning ~ practise replanting of trees ~ find other alternatives of energy sources such as solar, wind and geothermal energy. ~ abide the Kyoto protocol; an International treaty sign by countries committed to the deduction of release in greenhouse gases.

2. THINNING OF THE OZONE LAYER - Ozone layer is present in the stratosphere which is above the Earth’s atmosphere, 12-25 kilometres above the Earth’s surface. - Ozone layer protects the Earth from the harmful effects of ultraviolet (UV) radiation. -High concentrations of ozone, which is mainly, the (O3), in the ozone layer, have the ability to absorb large amounts of UV radiation. - We must beware, that, ozone, although is in the form of oxygen, will not be replenished naturally once it is depleted. - The main cause of ozone depletion is the increasing level of chlorofluorocarbons (CFCs) in the atmosphere. - CFCs are widely used as coolants in air conditioner as well as in refrigerators, as propellants in aerosol cans, as solvents in electronics industries and as foaming agents in the production of polystyrene boxes. - CFCs are unreactive and can remain unchanged for over 100 years. - UV radiation breaks down CFCs, releasing chlorine radicals which destroy ozone in a chain reaction. It is estimated that a single chlorine atom can destroy 100 thousand molecules of ozone in a year. - Thus, the thinner the ozone layer, the more UV radiation would be able to reach the Earth’s surface. Prolonged exposure to UV radiation leads to the following cases.

HUMAN HEALTH ~ Skin cancer or melanoma ~ Cataract damage ~ Low immune system

PLANTS ~ Damage of leaf cells and chlorophyll, reducing photosynthesis. ~ Decrease in the nutrient content and crop yields. ~Killing of phytoplankton.

THE ENVIRONMENT ~ Temperature increases. ~ Changes in wind directions. ~ Climatic changes.

IMPACT OF THINNING OF OZONE LAYER AND GLOBAL WARMING ON THE ECOSYSTEM

Sea water becomes warm due to global warming results in a declination in zooplanktons. Ecosystem’s food web disturbed.

Coral reefs, wetlands, polarseas and temperate forests are slowly losing its flora and fauna.

Drought causes lands to dry. Ecosystem is disrupted as the producers, the plants cannot thrive.

UV radiation affects photosynthesis. Aquatic organisms are sensitive to UV. .

THE NEED FOR DEVELOPMENT AND THE EFFECTS OF AN INCREASING POPULATION ON THE ECOSYSTEM. As human population increases, the need to fulfill humans’ demands also increase. The demands are like the need for homes, roads and factories. Thus, there are more deforestation, more wastes are dumped and more burning of fossil fuels. The effects of an increase in population on the ecosystem include: 1. 2. 3. 4.

Soil erosion, landslides, extinction of flora and fauna Water, air, thermal and noise pollution as a result of human activities. Depletion of natural resources like coals, oils and minerals. Greenhouse effect and global warming due to open burning. Combustion of fossil fuels, burning of forests and farms. 5. Eutrophication and water pollution due to increasing usage of pesticides, herbicides and fungicides in agriculture. Honestly, these effects threaten our lives and the ecosystem. Emphasize on the development must be reduced. A balance between development projects and environment management must be created as fast as possible.

MEASURES TO ENSURE A BALANCE OF NATURE IS MAINTAINED 1. IMPLEMENTATION OF LAWS - Among the enacted laws and regulations by the government are: (a) Enviromental Quality Act 1974,1985 A principal legislation in regulating the prevention, abatement and control of pollution as well as the enhancement of the environment. Among the regulations included here are: (i) (ii) (iii) (iv) (v)

Sewage and Industrial Effluents Regulation 1979 Motor Vehicle Noise Regulations 1987 Environment Impact Assessment Order 1987 Control of Emission from Diesel Engines Regulation 1996 Clean Air Regulations 2000

(b) National Forestry Act 1984 - It aims is at protecting and preserving our forests and wildlife. (c) Pesticides Act 1974 - It aims at controlling the use of pesticides. (d) Protection of Wildlife Act 1972 -

It aims at protecting wild animals, birds and plants.

(e) Fisheries Act 1985 - It aims at controlling marine pollution. Apart from national laws, meetings and forums were held internationally to discuss ways to protect our environment. For instance, Earth Summit was held in Rio De Janeiro in1992, Langkawi Declaration in Langkawi 1989 and Protocol Montreal 1987.

2. USES OF TECHNOLOGIES - Rubbish is sorted into recyclable materials and non-recyclable materials. The nonrecyclable materials can be burnt in incinerators where heat formed can be reclaimed and being used in heating or to generate electricity. - Catalytic converters are used to reduce the amount of nitrogen oxides emitted and convert harmful gases released during combustion of fossil fuels into less harmful matters. - Unleaded petrol can be used to replace leaded petrol. - Solar energy can generate cars and can reduce the combustion of fossil fuels. - Chimneys of factories are fixed with filters as to impair the amount of air pollutants. - Sewage is treated before it is discharged into water to reduce water pollution. - Agricultural waste can be converted to methane gas. -Bacteria can aid in the breakdown of oil which is spilled in the sea water.

3. EDUCATION - Education is essential to teach public about the importance of maintaining a balanced ecosystem. Here, in Malaysia, environmental education is one aspect of the National Education Philosophy. - Below are the objectives of the environmental education: a) to increase awareness of individuals and society towards the environment and its problems. b) To impart knowledge to individuals and society on the environment, problems on the environment as well as their duties and responsibilities. c) to care and protect the environment for the sake of a balance living. d) To acquire skills that can solve environmental problems. - Formal education is carried out in schools, colleges and institutions. Mobile education units visit schools to give talks and film shows which concern about the environment. Meanwhile, informal education is carried out through mass media, campaigns, seminars, brochures, magazines and films. -The 3R concept is basically one of the educations on management of resources ideas. 3R refers to as reduce, reuse and recycle. - Lesser demand in obtaining natural sources when recycle method is being implemented by all. Newspapers, glass, bottles and aluminium cans can be recycled. Meanwhile, empty cans, bottles or plastic bags can be reuse. - Education on the effects and causes of pollution, the usage of metal food containers to replace polystyrene boxed and the usage of shopping baskets rather than using plastic bags can be highlighted in schools.

4. PRESERVATION AND CONSERVATION - Biodiversity can be maintained if we preserve and conserve the forests and mangrove swamps. - Preservation involves efforts and measures taken to protect the ecosystem so as to maintain a balance of nature. - Conservation involves steps and efforts taken to return an imbalanced ecosystem to its natural equilibrium. - Measures taken to preserve and conserve our environment are: (a) (b) (c) (d) (e) (f)

control of grazing by animals farming along contours crop rotation cultivation on terraces proper use of fertilisers effective irrigation and drainage

- In order to sustain a continuous supply of clean water, our water sources must be preserved. Among the methods taken to preserve and conserve our water sources and water catchments areas are by educating public to take care and love the rivers, lakes, seas and enforcing laws to prevent pollution. - How about our mangrove swamps? Mangrove swamps play a vital role in controlling flood, coastal erosion prevention, sediment control and also as barriers against strong sea waves such as the tsunami strikes.

-The mangrove trees are used for pilling in construction, building materials and as a source of fuel. Clearing of mangrove swamps for its timber robs the flora and fauna found in the swamps, so efforts must be toyed up to preserve and conserve our mangrove swamps. -Laws prohibiting random tree felling, hunting and farming must be enforced strictly. -Forest reserves are gazetted. Replanting of trees must be carried out. -Reforestation ensures that forests are renewed. Restoration activities should be conducted to restore damage forests.

5. BIOLOGICAL CONTROL -This method is an alternative method rather than using pesticides to get rid of pests -Pesticides are not only expensive and toxic to non-pest; they actually make pests more resistance to pesticides used. -Biological control involves the use of the pest’s natural predator to keep the population of the pest at the minimum level. -Examples of the usage of biological control are: (a) Female hoverfly is used to control aphids which suck the nutrient of wheat plants. (b) A bacterium called Bacillus thuringiensis can kill caterpillars on cabbages. (c) Owl is used to control the population of rates in oil palm plantation.

6. RENEWABLE ENERGY - Renewable energy is the energy that occurs naturally and is inexhaustible. It does not give rise to pollution. -Examples of renewable energy are: (a) solar energy by the Sun (b) wind energy (c) hydroelectric

(d) geothermic energy (e) biomass energy (f) wave energy

7. EFFICIENT USE OF ENERGY - We are using non-renewable energy from fossil fuels at an alarming rate. We must take notice that those non-renewable energies we use will be exhausted and cannot be renewed if its usage is not controlled. - Improve fuel efficiency in motorized vehicles and also in factories by modifying the engines and machines. Right now, several scientists are working on the hydrogen fuel that can be used in motor vehicles in the future, which does not cause pollution. - Use natural gas and reduce combustion of fossil fuels, and not to mention stop open burning. Natural gas like ethanol or methanol obtained from the waste of crops and animals can be used alternatives sources of fuel since they give off less emission of toxic gases and giving great mileage and performance to vehicles either.

8. ACTIVITIES RELATED TO THE MANAGEMENT OF THE ECOSYSTEM - Due to modernity, human activities cause an imbalanced ecosystem or in the near future, may also destroy an ecosystem. - We should not be too eager. Awareness on the threatening activities of human beings toward the ecosystem must be imparted in all mankind. For example, dumping rubbish and toxic wastes into rivers and drains can lead to water pollution. The rivers and drains will then be breeding grounds for mosquitoes. The decaying rubbish also attracts rats,

flies and animals vectors. After that, human beings have to suffer from various illnesses like dengue fever and so on. - Many activities can be working on to encourage students to care for the ecosystem. In schools, there must be activities on building up fish pond, setting up a garden and also on recycling materials. - “:Gotong-royong” is another initiative that can be carried out to keep the school and the environment at home clean. - Campaigns such as the “Environment Day” and “Recycling Day” can also be carried out at school.