H.S.B research that was carried out on The Impact of Heath Practices on the Environment. This will help to guide you as to how you should go about doing this assignment.

1. Raheme Matthie
Teacher: MissWilliams
Subject: Humanand SocialBiology
Date Submitted: February ,2013

2. CONTENT

3. 1# DEFINITION OF THE TERM POLLUTION
Pollution is the introduction of contaminants into the natural environment that cause harm or
adverse change to human health, or other living organisms and the environment. Pollution can
take the form of chemical substances or energy, such as noise, heat or light. Pollutants, the
components of pollution, can be either foreign substances/energies or naturally occurring
contaminants such as litter, chemicals, fumes, pesticides or organic wastes. Pollution is often
classed as point source or nonpoint source pollution.

4. #2 WHAT IS A POLLUTANT?
A pollutant is a substance or energy introduced into the environment that has undesired or
harmful effects.
It can also be described as any substance, as certain chemicals or waste products, which renders
the air, soil, water, or other natural resource harmful or unsuitable for a specific purpose. A
pollutant may cause long- or short-term damage by changing the growth rate of plant or animal
species, or by interfering with human amenities, comfort, health, or property values. Some
pollutants are biodegradable and therefore will not persist in the environment in the long term.
However the degradation products of some pollutants are themselves polluting such as the
products DDE and DDD produced from degradation of DDT. Pollutants can be artificial
substances, such as pesticides and PCBs, or naturally occurring substances, such as oil or carbon
dioxide, that occur in harmful concentrations in a given environment. Heat transmitted to natural
waterways through warm-water discharge from power plants and uncontained radioactivity from
nuclear wastes is also considered pollutants.

5. 3# THE EFFECTS OF POLLUTANTS ON THE ENVIRONMENT
There are various types of pollution for example air, water, and land pollution. It affects
everything in the world and is everywhere; it even affects remote places like the Arctic. There is
nowhere on the planet that is not polluted.
Air pollution is the contamination of air by the discharge of harmful substance. Air pollution
comes from burning of fossils fuels to produce electricity, from vehicle exhaust fumes and
factory chimneys and from refrigeration systems, which release harmful chemicals (CFCs). Air
pollution harms humans. It causes health problems such as burning eyes and nose. There are also
more serious health problems that it can cause, some chemicals can cause cancer, birth defects,
brain, and nerve damage. When we breathe in, dust and pollutants in the air get into out lungs.
Respiratory diseases like bronchitis, cancer and emphysema are more common in areas where air
is highly polluted. Air pollution damages the ozone layer that protects us from the harmful
ultraviolet rays from the sun. Air pollution also affects plants; it interferes with photosynthesis so
the plants cannot properly make their own food. It affects the fruits the plants grow and make
them smaller and less nutritious.
Water pollution is the addition of harmful materials to a body of water in concentrations that
affect its quality. Water pollution kills life that lives in water. Water pollution also affects the
food chain when smaller organisms eat it and are than eaten by larger ones eventually humans
come into the food chain too. People can get hepatitis by eating poisoned seafood. Plants are also
affected by water pollution. As people dump chemicals into the water the plants there are
affected by it. The chemicals work as a fertilizer by making the plants grow as they grow they
need more and more oxygen that they used to share with other organisms that lived there. As the
plants die from their lack of water they have to decompose which uses even more oxygen, which
the fish and other organisms need to survive. This causes the whole ecosystem to be unbalanced.
Land pollution is the addition of undesirable matter to the land that may damage organisms.
Mainly herbicides and pesticides pollute soil.

6. Land can also become contaminated by activities such as mining and improper waste disposal.
Air pollution also affects Land pollution, acid rain caused by air pollution comes down and soaks
into the ground and pollutes all the ground water. Because all water leads to the ocean even the
polluted ground water will get to the ocean and pollute it too.
The Earth has very fragile ecosystems and pollution takes away the balance of all of them.
Humans should learn proper ways of disposing their waste.

7. #4 THE METHOD OF CONTROLLING POLLUTION
Pollution is caused by mainly human activities on the environment. Burning fossil fuels and
exhaust from motor vehicles are some of the leading causes of air pollution. Sewage from
domestic users and Oil spilled from tankers are the biggest sources of water pollution. In order
for us to improve the quality of our air and water we have to established and implement ways of
preventing and controlling pollution. All over the world, environmental organizations and
individuals are working towards reducing the effects of human damage on the environment; as a
result different methods have been assembled as to help resolve these problems.
Reducing emissions – Emissions are substances discharged into the environment,
particular carbon containing pollutants, from industry and vehicles. Industries can put measures
in place to prevent and control emissions and pollutants. Motor car manufacturers can help to
prevent pollution. Most modern cars have catalytic converters in the exhaust systems. The
catalyst oxidizes poisonous carbon monoxide into less harmful carbon dioxide. Lead free petrol
help to reduce lead levels in the atmosphere and modern diesels for cars are designed to be much
lower in sulphur.
Individual persons can also help to control pollution by the following methods
 Use renewable energy sources – find out whether your area offers electricity generated
by windmills, solar panels or other clean technology. Support these sources of energy, as
they will help to improve the level of pollution in the environment.
 Recycle and use recycled products – less power is used making products from recycled
materials than is used making them from new materials. Recycle paper reduces
deforestation, thus saving trees that can remove carbon from the atmosphere.
 Plant more trees – trees use CO₂ form the atmosphere to produce oxygen. A tree can
remove between 300 and 3000kg of carbon from the atmosphere during its lifespan. A
tree that shades your home can help to reduce the cost of running an air-conditioner.
Without trees we humans and other life forms would not be able to support life.
Therefore is very important that more trees are planted than cut down.

8.  Turn off heating devices, coolers and appliances– hot water cylinders and air-
conditioners use a lot of energy. Many public buildings use air-conditioners in their
buildings. I best advice that these buildings use these power consuming devices lees or if
possible not at all. The use of devices can be regulated as timer can be installed so that
you only use them for short periods during the day. Kitchen appliances, televisions,
computers, phone chargers and all other appliances all use power, even when they are
plugged in and switched off.
 Use less fossil fuel – cars and other vehicles are part of our everyday uses as a medium
for transport. The effects of exhaust from these motor vehicles can be reduced
significantly in your town or city, by using public transport, car pools and shared rides. If
business people sue the telephone and video conference technology instead of flying to
meetings, they save time, money and more importantly reduce the level of carbon
emissions released from the airplanes. If you walk or ride a bicycle instead of travelling
in a vehicle powered by fossil fuels, you can minimize the level of pollution caused
within your region.
 Use energy –efficient products/appliances -

9. #5 THE CAUSES OF WATER POLLUTION
In some un-developed countries, the sewage is not treated, but quickly dumped into the sea or
water bodies. This is VERY dangerous because they contaminate the environment and water
bodies and bring many deadly diseases to us. The causes of water pollution are as explained
below:
Septic Tanks
Every domestic (home) toilet is connected to septic tank usually located outside the house. Each
time excretory products are flushed down the toilet, it goes into this tank, where the solid part is
separated from the liquid part. Biological processes are used to break down the solids and the
liquid is usually drained out into a land drainage system. From this stage, it can escape into the
soil and nearby water bodies.
Ocean and marine dumping
think of the rubbish we all make each day. Paper waste,
food waste, plastic, rubber, metallic and aluminum waste.
In some countries, there are deposited into the sea. All
these waste types take time to decompose. Example, it is
known that paper takes about 600 years, aluminum takes
about 200 years and glass takes even more. When these end up in the sea, they remain there for
many years, as a result they harm sea
animals and cause a lot of deaths.

10. Industrial waste
Industries also cause huge water pollution with their activities. These come from:
Asbestos – This pollutant cancer-causing properties. When inhaled, it can cause illnesses such as
asbestosis and many types of cancer.
Lead and Mercury – These are metallic elements and can cause environmental and health
problems for humans and animals. It is even more poisonous. It is usually very hard to clean it up
from the environment once it get into it because it in non-biodegradable.
Nitrates & Phosphates– These are found in fertilizers are often washed from the soils to nearby
water bodies. They can cause eutrophication, which can be very problematic to marine
environments.
Sulphur – This is a non-metallic substance that is harmful for marine life.
Oils – Oils forms a thick layer on the water surface because they do not dissolve in water. This
can stop marine plants receiving enough light for photosynthesis. It is also harmful for fish and
marine birds. A classic example is the BP oil spill in 2012 with killed thousands of animal
species.
Oil Pollution
Routine shipping, run-offs and dumping of oils on the ocean surfaces happen every day. Oil
spills make up about 12% of the oil that enters the ocean. Oil spills cause major problems, and
can be extremely harmful to local marine wildlife such as fish, birds and sea otters and other

11. aquatic life. Because oil does not dissolve, it stays on the water surface and suffocates fish. Oil
also gets caught in the feathers of sea birds stopping them from flying. Some animals die as a
result.
Underground storage and tube leakages.
Many liquid products (petroleum products) are stored in metal and steel tubes underground.
Other sewage systems run in underground tubes. Overtime, they rust and begin to leak. If that
happens, they contaminate the soils and the liquids in them end up in many nearby water bodies.
Atmospheric
Atmospheric deposition is the pollution of water bodies caused by air pollution. Each time the air
is polluted with sulphur dioxide and nitrogen oxide, they mix with water particles in the air and
form a toxic substance. This falls as acid rain to the ground, and gets washed into water bodies.
The result is that, water bodies also get contaminated and this affects animals and water
organisms.
Agricultural pollutants
These can be described as fertilizer and pesticide run off. Rain washes fertilizers and pesticides
from farmlands into rivers and lakes. Once fertilizers get into the water sources they can increase
the level of ammonia which pollutes the water. Very few aquatic organisms can survive high
levels of ammonia. The result of this is the death of different species when they are exposed.
Nutrients in manure can stimulate the growth of algae. Algae grows very rapidly ‘nutrient
bloom’, which depletes the oxygen available to other organisms in the water and also blocks out
light. Manure also harbors dangerous bacteria, such as giardia and cryptosporidium. These
pathogens are a hazard for seafood eaters, sea organisms and swimmers.
Mud from construction sites and road building can also flow into rivers and dams and
affect plant and animal life.

12. #6 THE PROCESS OF LARGE SCALE WATER PURIFICATION
Water purification is the process of removing undesirable chemicals, biological contaminants,
suspended solids and gases from contaminated water. The goal is to produce water fit for a
specific purpose. Most water is purified for human consumption (drinking water), but water
purification may also be designed for a variety of other purposes, including meeting the
requirements of medical, pharmacological, chemical and industrial applications. In general the
methods used include physical processes such as filtration, sedimentation, and distillation,
biological processes such as slow sand filters or biologically active carbon, chemical processes
such as flocculation and chlorination and the use of electromagnetic radiation such as ultraviolet
light.
The purification process of water may reduce the concentration of particulate matter including
suspended particles, parasites, bacteria, algae, viruses, fungi; and a range of dissolved and
particulate material derived from the surfaces that water may have made contact with after
falling as rain.
Simple procedures such as boiling or the use of a household activated carbon filter are not
sufficient for treating all the possible contaminants that may be present in water from an
unknown source. Even natural spring water – considered safe for all practical purposes in the
19th century – must now be tested before determining what kind of treatment, if any, is needed.
Chemical and microbiological analysis, while expensive, are the only way to obtain the
information necessary for deciding on the appropriate method of purification. Simple techniques
for treating water at home, such as chlorination, filters, and solar disinfection, and storing it in
safe containers could save a huge number of lives each year. Reducing deaths from waterborne
diseases is a major public health goal in developing countries.
Large-scale or municipal water treatment is not common in rural communities but you may find
it in larger towns and cities where there is a network of pipes and pumps to distribute water from
the treatment works. There are several steps in municipal water treatment; intended to remove

13. solids, kill pathogenic organisms and make water safe to drink. The main stages are usually
aeration, sedimentation, coagulation, filtration and disinfection.
Aeration simply means to mix air with the water. It is used to remove volatile (easily
evaporated) substances from drinking water. Air and water are put into contact with each other,
i.e. air is bubbled through the water, so that the volatile substances are evaporated into the
airstream and removed from the water. Aeration can be carried out in towers or aeration basins to
provide the necessary contact time between air and water.
Sedimentation is the settling out of comparatively heavy suspended material (suspended solids)
in water because of gravity. The settling takes place in a quiet pond or a specially constructed
tank. A minimum 24-hour retention time is necessary to have a significant reduction in
suspended matter. (Retention time means the length of time the water is kept (retained) in the
tank.) Sedimentation can be used alone or in combination with coagulation.

14. #7 THE WATER CYCLE
The water cycle, also known as the hydrologic cycle or the H2O cycle, is a natural cycle which
depends on the energy of the sun, it describes the continuous movement of water on, above and
below the surface of the Earth. The water moves from one reservoir to another, such as a river to
ocean, or from the ocean to the atmosphere, by the physical processes of evaporation,
condensation, precipitation, infiltration, runoff, and subsurface flow. In so doing, the water goes
through different phases: liquid, solid (ice), and gas (vapor).
Water vapor rises in the atmosphere and cools down to form clouds. As the cloud rise,
they cool further and the water vapor changes back to liquid drops of water I the process of
condensation. When the water droplets get too heavy in the clouds they fall back to the Earth in
the form of rain or snow. Rain and snow are forms of precipitation.
The rainwater that is absorbed into the ground is filtered by rocks and soil. This filtration
removes solid particles from the water, and allows the liquid to soak through to reach the water
table which is a saturated layer of water at a particular depth below the soil.

15. The water cycle involves the exchange of heat, which leads to temperature changes. For
instance, when water evaporates, it takes up energy from its surroundings and cools the
environment. When it condenses, it releases energy and warms the environment. These heat
exchanges influence climate. By transferring water from one reservoir to another, the water cycle
purifies water, replenishes the land with freshwater, and transports minerals to different parts of
the globe. It is also involved in reshaping the geological features of the Earth, through such
processes as erosion and sedimentation. The whole cycle is repeated continually it figures
significantly in the maintenance of life and ecosystems on Earth.

16. #8 THE STAGES OF WATER PURIFICATION

17. #9 SIMPLE WAYS OF PURIFYING WATER,
WITHIN THE HOME
Water that we use daily contains algae, bacteria, protozoa or virus; all these can make you very
ill if you drink it. Chemicals in water can affect its taste and quality and can also cause stomach
upsets. It is best advised to purify water before drinking it. There are several methods that you
can utilize to do this, these methods are described here.
Boiling
Boiling is one of the simplest and most effective methods of purifying water. This is done by
using a clean container placed over a heat source until it bubbles ( comes to a rolling boil). With
the heat reduced allow it to boil for 5 – 10 minutes. The heat will kill pathogens and make the
water safe to drink. Once it has boiled, cover the water and let cool. Store in a clean, sealed
container.
Adding Chemicals
You can use small amounts of plain household chlorine bleach, dilute iodine or potassium
permanganate to purify water.
 Bleach – pour water into a clean container. A dropper can be used to add bleach at a rate
of 1 - 2 droppings per litre of water. If he water is cloudy at first, then double the amount.
Sir the water for even distribution of the bleach and let stand for half an hour before
drinking. Don’t add more than 5 drops per litre.
 Dilute Iodine – use a 2% solution of iodine. Put the water in a clean container and add 5
drops per litre to the water. Double this amount if the water is cloudy to start with. Stir
the mixture and allow it to stand for half an hour before drinking.
 Potassium permanganate - Pour water into a clean container. Add three or four
crystals per litre and allow it to dissolve. Stir the water and let it stand for half an hour
before using.

18. Once you have purified the water, you need to store in a sealed container to prevent new
microorganisms from contaminating it. A pinch of salt can be added as to enhance the
taste of the water.
Water that is muddy and contains solid particles, can be filtered to get rid of the
solids before purifying it.

19. #10 HOW CAN WATER BE TESTED FOR BACTERIA?
How do I collect a sample of water for bacteria testing?
A proper container must be used to collect the sample.
1. To collect all samples, a sterile microbiological sample container, which contains 1-
sodium thiosulphate pill (to neutralize chlorine), should be used.
2. Sample containers should be kept clean and free from contamination before and after
collecting the sample. They should not be opened prior to collecting the sample.
3. At locations where the sample must be collected from a tap, inspect the outside of the
faucet. If water leaks around the outside of the faucet, select a different sampling site.
Remove any aerators, strainers, hose attachments, mixing type faucets, and purification
devices from the tap.
Run the cold water for at least three minutes before sample collection.
4. Reduce the tap flow rate before taking the sample. The flow rate should be low enough to
ensure that no splashing occurs as the container is filled. At sampling points where water
runs continuously, do not adjust flow rate.
5. Identify all containers and complete the corresponding requisition. All raw water samples
are to be identified.
6. While holding the sample container at the base, carefully flip the top cover up, (there will
be some resistence), using the tab, hold the flip lid back from the water source. Be careful
not to touch the edge, the underneath of the flip lid or the top and/or inside of the sample
container. If the sample container is cracked or appears dirty or if you suspect there are
any other conditions which places the quality of the container in doubt, it is to be rejected
and replaced with another sample container. Care is to be exercised to prevent breathing
directly on the inside of the flip lid and also the container.
7. The sample container is to be filled over the "100 mL fill line", not under which leaves
enough air space in the container to allow for mixing by shaking in the lab. The flip lid is
carefully replaced and the security string is inserted, this will secure the tab and flip lid in
place.
8. Samples shall be transported to the laboratory within 24 hours. It is recommended that
samples be kept at <10oC (in a refrigerator or cooler with ice packs) until delivered to the
lab.

20. #11 THE IMPACT OF HUMAN ACTIVITIES
ON WATER SUPPLIES
Humans impact the earth both directly and indirectly. Our mere presence on this planet or the
state of being “alive” and breathing produces carbon dioxide, a known depletory of the ozone.
Industrialization, production, agriculture, land-use practices, hydropower generation, fossil fuel
and nuclear power generation, disposal of wastes, and our ever-lasting desire for consumption to
obtain more, whether it be material objects or material items, causing devastating impacts to our
ecosystems and water sources. We use water for such tasks as bathing to watering our garden,
not to mention that it comprises nearly 70% of our body. It is for these reasons that we need to
take careful steps to reduce negative impacts.
There are many things we can do in our daily activities to conserve our water supply. The
simplest but the most often forgotten is to NOT WASTE WATER! If you have a leaky faucet or
running toilet, fix it! Brush your teeth with the water off, limit baths taken and shower time, or
purchase a showerhead that regulates water flow from the tap.
Agriculture plays a considerable role in the quality of water. We need the agricultural industry,
to sustain our food supply. However, the practices used have harmful effects on neighboring
watersheds. Three factors come into play when considering agriculture and human wastes:
Pesticides, fertilizers and the waste produced by our farm animals, and non-existent sewage
disposal systems. Fertilizers are excess nutrients and they are applied to aid growth; pesticides
are chemicals to kill or repel pests; and wastes are excess nutrients excreted by farm animals
such as nitrogen and phosphorus. When pesticides or fertilizers are applied to crops, there is
evident probability that there will be runoff. The excess materials will either run off the land, or
seep into the groundwater, with an eventual ending in bodies of water such as lakes, ponds, or
streams. Fertilizer, pesticides, and excess nutrient wastes by farm animals, and non-existent
sewage management plans may contaminate freshwater ecosystems and harm plants, animals,
insects, and fish that rely on this freshwater for their habitats.

21. We all need nutrients for growth and reproduction. However, excess nutrients lead to a common
problem known as an “algal bloom.” This causes an overproduction of algae, which limits
sunlight reaching lower waters, and reduces dissolved oxygen. Plants cannot live without
sunlight, and as a consequence they will die. Much aquatic life depends on plants as their food
mainstay, so they too will die off. The reduction of dissolved oxygen occurs as plants die and
decay at the bottom of the the water. Bacteria consume oxygen, which leaves limited amounts
for the other present organisms that depend on it, thus killing them off too.
Another human impact on water quality is the implementation of sewage treatment plants. Until
just recently, sewage treatment plants were not a widespread practice. At present, there are still
many townships and municipalities that have no means of disposing of household waste. Where
does it go? If you live by a lake or pond, most likely your waste goes into that beautiful body of
water that you swim in, or goes into a septic tank that is possibly out of date or not maintained
properly. Waste is excess nutrients. It has the same effect as fertilizers and animal waste.
However, human waste may contain harmful elements that can cause human disease such as E.
coli and ????.
The mining industry has also impacted the quality of water. The mining industry had its start
back in the mid 1700’s. In these early days there were no measures employed to protect our
environment, so our earth has taken a burden of destruction and bad practices. The most
prevalent impact on water quality has been the discharges from abandoned mines containing
heavy metals, sulfates, and acid, all entering our waterways. The resulting problems include
contaminated drinking water, corrosion of road and rail network structures, and disturbed growth
of plants and animals trying to live in the tainted water. If your waterway is contaminated, it will
most likely have a red, orange, or yellow tinge of the sediment.
It is recommended that you follow guidelines or get needed assistance when using fertilizers and
pesticides. There are programs and plans that aid those employed in the agricultural industry to
help protect their watersheds. These include sewage treatment plants, implementation of nutrient
management plans, planting forest buffers, storm water management ponds, or digging of
manure pits.

22. Everything humans do, even our mere existence, affects the quality of the water on earth. We
should implement practices and policies to preserve the quality of our water, for water is one of
the most valuable natural resources left in the world, and we depend on it greatly.

23. WHY CONTAMINATED WATER IS DERIMENTAL
TO HUMAN BEINGS
Water is easily polluted and water pollution is one of the most serious forms of contamination in
an ecosystem. Contaminated water is harmful to human beings because it contains disease-
causing organisms, which can impact seriously on human health. Cleaning agents can cause
water to foam, which makes it undrinkable and toxic.
People are increasingly concerned about the safety of their drinking water. As improvements in
analytical methods allow us to detect impurities at very low concentrations in water, water
supplies once considered pure are found to have contaminants. We cannot expect pure water, but
we want safe water.
The health effects of some contaminants in drinking water are not well understood, but the
presence of contaminants does not mean that your health will be harmed. In North Carolina,
drinking water is generally of high quality and free from significant contamination. Public water
supplies are tested, and regulated to ensure that our water remains free from unsafe levels of
contamination. Small private water supplies, including wells, are not regulated by drinking water
standards, and the owner must take steps to test and treat the water as needed to avoid possible
health risks.
What is in your drinking water? The only way to know is to have it tested.
Drinking water can become contaminated at the original water source, during treatment, or
during distribution to the home.
 If your water comes from surface water (river or lake), it can be exposed to acid rain,
storm water runoff, pesticide runoff, and industrial waste. This water is cleansed
somewhat by exposure to sunlight, aeration, and micro-organisms in the water.

24.  If your water comes from groundwater (private wells and some public water
supplies), it generally takes longer to become contaminated but the natural cleansing
process also may take much longer. Groundwater moves slowly and is not exposed to
sunlight, aeration, or aerobic (requiring oxygen) micro-organisms. Groundwater can be
contaminated by disease-producing pathogens, leachate from landfills and septic systems,
careless disposal of hazardous household products, agricultural chemicals, and leaking
underground storage tanks.

25. SEWAGE
Sewage is a mixture of waste and water. Most sewage consists of water mixed with:
 Household waste water from kitchens and bathroom drainage
 Feaces and urine from toilets
 Industrial wastes flushed or released into drains
 Oil or other road debris washed from roads into the sewage systems
Sewage runs into the sewerage systems, which is designed to carry the materials to different
treatment plants. At the treatment plant, the sewage is treated and cleaned before it is returned to
the environment.

26. PROPER AND IMPROPER SEWAGE
DISPOSAL PRACTICES
Proper sewage disposal is getting rid sewage in the most environmentally and human friendly
way as possible whilst improper sewage disposal is the opposite. It causes the wide spread of
many diseases and poses as a health problem for human beings. Disease-causing bacteria can
contaminate drinking water supplies and be transported by flies, rodents and dogs. Proper
sewage disposal methods are essential to control disease-causing bacteria, to remove and
stabilize organic material, avoid the contamination of drinking water and reduce unpleasant
odors and unsightly appearance.
Porper idposal: Moden disposal even residential weaste, involves splitting upt he waste so that it
goes to the proper container and ultimately the proper treatment . Recycling, sewage, old food
and general garbage all get treated differently.
Inmproper disposal: means that hazardous material enter the environment and require removal,
clean up-up or neutralization according 5

27. THE IMPACT OF PROPER SEWAGE
DISPOSAL PRACTICES

28. THE ROLE OF MICRO ORGANISMS IN THE
TREATMENT OF SEWAGE
Sewage contains large numbers of microorganisms. These organisms help to break down organic
material in the sewage. However, as they do this, they use oxygen from the water and excrete
harmful substances. Hen sewage is dumped in water supplies, this process can reduce the oxygen
content and organisms that live in the water die from lack of oxygen or from exposure to harmful
substances. The only organism s that can survive are – anaerobic bacteria, they don’t need
oxygen – and these continue to decompose the organism wastes causing the water to become
dark green or black and very smelly.

29. THE TREATMENT OF SEWAGE BY BIOLOGICAL FILTER
AND SLUDGE METHOD

30. THE PARTS OF A PIT LATRINE AND THEIR FUNCTIONS
Part Function
Pit Collects urine, faeces and allows it to decompose and
to be absorbed into the soil
Lid Seals the opening when not in use, prevents insects
and rodents from entering the pit, and contains odors
Latrine House Provides privacy, allows the area to be screened off to
keep insects out of the latrine
Pit Lining Provides support for the toilet, prevents the top of the
pit from collapsing and keeps the floor dry/easy to
clean
Latrine opening Opening to the pit, allows passage of urine and faeces
as well as cleaning materials such as toilets paper
Sloped roof Allows rainwater to run off and prevents it from
entering the latrine or the pit
Vent Pipe Allows air to circulate and removes odors from the pit
Pipe Screen Prevents insects and other pests from entering the pipe

31. Bibliography
JoannaGeorge-Johnson,K.M. (2010). Human and Social Biology forCSEC examination. London:Hodder
Education.