untuk kegunaan enviroment

1. QUESTION 1
Explain the two types of diseases :
a. Communicable
Communicable diseases, also known as infectious diseases or transmissible diseases,
are illnesses that result from the infection, presence and growth of pathogenic (capable
of causing disease) biologic agents in an individual human or other animal host.
Infections may range in severity from asymptomatic (without symptoms) to severe and
fatal. The term infection does not have the same meaning as infectious disease because
some infections do not cause illness in a host.
Disease causing biologic agents include viruses, bacteria, fungi, protozoa, multicellular
parasites, and aberrant proteins known as prions. Transmission of these biologic agents
can occur in a variety of ways, including direct physical contact with an infectious
person, consuming contaminated foods or beverages, contact with contaminated body
fluids, contact with contaminated inanimate objects, airborne (inhalation), or being bitten
by an infected insect or tick. Some disease agents can be transmitted from animals to
humans, and some of these agents can be transmitted in more than one way.
b. Non communicable
Non-communicable diseases (NCD) is a non-contagious disease process or transferred
from one human to another. Random genetic abnormalities, heredity, lifestyle or
environment can cause a patient to get diseases such as cancer, diabetes, asthma,
hypertension, and osteoporosis. All these diseases cannot be transmitted. Autoimmune
disease, trauma, fractures, mental disorders, malnutrition, toxicity and hormonal
conditions in the category of non-communicable diseases.
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2. Question 2
Explain the types of communicable disease caused by pollution
a. Water Borne Disease
Waterborne diseases are caused by pathogenic microorganisms that most commonly
are transmitted in contaminated fresh water. Infection commonly results during bathing,
washing, drinking, in the preparation of food, or the consumption of food thus infected.
Various forms of waterborne diarrheal disease probably are the most prominent
examples, and affect mainly children in developing countries; according to the World
Health Organization, such disease account for an estimated 4.1% of the total DALY
global burden of disease, and cause about 1.8 million human deaths annually. The
World Health Organization estimates that 88% of that burden is attributable to unsafe
water supply, sanitation and hygiene. Some examples of communicable water borne
disease are:
· Cholera
· Bacillary Dysentery/Shigellosis
· Hepatitis A
· Typhoid fever
b. Food Borne Disease
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3. Foodborne illness (also foodborne disease and colloquially referred to as food
poisoning) is any illness resulting from the consumption of contaminated food,
pathogenic bacteria, viruses, or parasites that contaminate food, as well as chemical or
natural toxins such as poisonous mushrooms. Some examples of communicable food
borne disease are:
· E. Coli Infection
· Salmonellosis
· Shigellosis
· Norovirus Infection
· Botulism
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4. c. Insect Borne Diseases
Of the many diseases spread by insects, very few are actually caused by the insects
themselves but rather, by other organisms passed on when they feed or bite. Insects are
capable of spreading diseases caused by many different types of micro-organisms
including bacteria, viruses, protozoans, etc. In these instances it is the micro-organism
that is the pathogen (disease causer) and the insect involved is known as the vector.
Biting insects are active at all times of the day and night. However, some prefer different
times of day eg. the mosquitoes that spread malaria are mainly active after dark but the
mosquitoes that spread yellow fever and dengue fever are active during daylight hours.
Some examples of communicable insect borne disease are:
· Malaria
· Yellow Fever
· Dengue Fever
· West Nile Virus
· Tick Borne Encephalitis
d. Rodent Borne Disease
Rodentia is the order of mammals known as rodents, characterised by a single pair of
continuously growing incisors in each of the upper and lower jaws which must be kept
short by gnawing.
Forty percent of mammal species are rodents, and they are found in vast numbers on all
continents other than Antarctica. Common rodents include mice, rats, squirrels,
porcupines, beavers, guinea pigs, and hamsters. Rodents use their sharp incisors to
gnaw wood, break into food, and bite predators. Most rodents eat seeds or plants,
though some have more varied diets. Some species have historically been pests, eating
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5. seeds stored by people and spreading disease. Some examples of communicable
rodent borne disease are:
· Weil’s Syndrome
· Plague
· Bubonic Plague
· Rat-borne Disease.
· Bat-borne Disease.
Question 3
Explain the types of non-communicable diseases caused by pollution:
a. Lead (plumbum)
Acute or chronic poisoning by lead or any of its salts, with the acute form causing severe
gastroenteritis and encephalopathy and the chronic form causing anemia and damage to
the gastrointestinal tract and nervous system. Also called saturnism.
b. Mercury
Sunburn and heat stroke are examples of some diseases caused by physical agents.
Chemical agents which cause diseases are lead, mercury, potassium, cyanide, snake
bite, poisoning from plants
c. Insecticides
Two insecticides that cause health problems are lindane and methoxychlor. Excessive
consumption of lindane is known to cause liver and kidney disorders. Excessive
consumption of methoxycholor has been linked to reproductive disorders.
d. Asbestos
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6. Asbestos-related diseases are generally associated with exposure to high levels of
asbestos over an extended period of time. Studies on workers in mines, factories and
shipyards have shown that heavy exposures to asbestos can lead to three serious
diseases:
· asbestosis (scarring of lung tissue),
· lung cancer , and
· mesothelioma (a rare form of cancer affecting the lining of the lungs).
e. Cadmium
Cadmium is first transported to the liver through the blood. There, it is bond to proteins to
form complexes that are transported to the kidneys. Cadmium accumulates in kidneys,
where it damages filtering mechanisms. This causes the excretion of essential proteins
and sugars from the body and further kidney damage. It takes a very long time before
cadmium that has accumulated in kidneys is excreted from a human body.
Other health effects that can be caused by cadmium are:
- Diarrhoea, stomach pains and severe vomiting
- Bone fracture
- Reproductive failure and possibly even infertility
- Damage to the central nervous system
- Damage to the immune system
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7. - Psychological disorders
- Possibly DNA damage or cancer development
f. Nitrateparticulate
· can be defined as the availability of gas, liquid or particles contained in the air
until the change and affect the life or other materials.
· Such materials suspended in the air and a negative impact on humans, plants
and animals.
· This is due to these materials will enter the human body through breathing and
can block the flow of oxygen into the blood vessels.
· This can cause a variety of diseases such as cramperd disease, cancer, asthma,
cramps and anemia.
· Dust, fumes, mists, vapors or other substances that can prevent eye sight is the
various forms of air pollution.
g. Dioxin
· Dioxins are toxins contained in the basic material for the manufacture of
processed paper products, sanitary napkins, baby diapers and so on.
· It is classified as a super toxic resulting from the reaction of the bleaching
chlorine process.Dioxin 120 times strength than arsenic.
· Use pads containing dioxins can cause hormonal imbalance
· Early signs of gynecological cancer Vagina Affect Fertility absorb anything and at
any time.
· When you insert the chemical into the vagina, the material will be in the blood
vessels and a half hours later.
Question 4
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8. Explain the sources ground water pollution :
a. Industrial waste
One of the major causes of water pollution is the discharge of wastes from industries. It
is a common observation that industries find rivers and the sea a comfortable place to
dump their waste material into. These wastes contain toxic substances and also include
elements like lead, mercury, nitrates and sulfates. They are quite harmful for humans as
well as aquatic animals. A large amount of money is wasted on treating the water bodies
that get contaminated and making them suitable to use for drinking purposes again.
Moreover, there are still risks of various diseases after consuming the water containing
such toxic materials. Often, hot or contaminated water is also released into the rivers
from these industries, which increases the overall temperature of the rivers, thus making
them unfavorable for the aquatic flora and fauna.
b. Domestic waste
Also known as "municipal solid waste", domestic waste is waste that is generated as a
result of the ordinary day-to-day use of a domestic premise and either :
a. taken from the premises by or on behalf of the person who generated the waste
b. collected by or on behalf of a local government as part of a waste collection and
disposal system.
c. Municipal landfill
Water pollution from landfills is a major problem in countries around the world.
Chemicals from fertilizers, organic human waste, and metal are the leading causes of
water contamination from landfills. The process of leaching, where water is filtered
through layers of trash, can allow the contaminated water to enter local water sources
easily. Household waste, including batteries and other common items, also contribute
significantly.
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9. d. Agriculture
Agricultural production leaves considerable amounts of agricultural waste. Some of it is
recycled into the agricultural production as fertilizer, while large amounts remain unused –
and in many instances pose a disposal problem. Uncontrolled burning in the fields is not
only a hazardous disposal solution - it is also wasting useful energy. With efficient collection
systems, waste from agricultural production can be utilised as fuel for power and heat
production.
In some agricultural industries large amounts of biomass waste is already concentrated and
readily available for utilisation. The palm oil industry, for instance, produces significant
amounts of empty fruit bunches that can be incinerated. Liquid wastes may also be
methanized and can secure a basis for own power and process heat production while
delivering excess power to the grid. In the sugar industry, significant amounts of bagasse –
the waste after extraction of sugar – is an equally excellent fuel. Rice production may also
be industrialised to such an extent that rice husks are available in amounts sufficient for
incineration in a boiler, thereby securing a basis for power and heat production.
In the forest industry, large concentrations of biomass waste can be utilised for power and
heat production, e.g. at sawmills. The forest industry also supplies raw material for
briquettes production, where sawdust, charcoal dust, degradable waste paper and dust from
agricultural production may constitute a final utilisation of waste materials from agriculture
related production. The following sectors of agricultural waste utilisation are presented in
this section:
· Waste in Forest Industry
· Waste in Other Agricultural Industries
· Waste in Palm Oil Industries
· Waste in Rice Industry
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10. Question 5
The phenomena of eutrophication:
1. Explain the eutrophication process occurred in a lake and its effects
During the rainy season, water influx with high organic content from the mainland is the
main source of the element for phytoplankton growth. The process by which a body of water
acquires a high concentration of nutrients, especially phosphates and nitrates. These
typically promote excessive growth of algae. As the algae die and decompose, high levels of
organic matter and the decomposing organisms deplete the water of available oxygen,
causing the death of other organisms, such as fish. Eutrophication is a natural, slow-aging
process for a water body, but human activity greatly speeds up the process.
2. Explain the causes of eutrophication
In the natural course of events, lakes and other bodies of freshwater receive nutrients like
phosphorus and nitrogen. The gradual accumulation of these nutrients involves a process
called eutrophication. As the lake ages, the nutrients build up with various effects. The
process speeds up with cultural eutrophication, which involves the effects of man on the
freshwater body.
· lakes become cloudy
· This phenomenon will cause severe water quality and is not suitable for some
applications.
· life in the water disturbed by this phenomenon
· germs spread disease
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11. · soil disturbance and quality
· soil erosion
3. Identity the methods of eutrophication
The eutrophication of a lake can be controlled or its effects on water minimized by
reducing the nutrient input to the lake; increasing nutrient output from the lake,
immobilizing nutrients within the lake and controlling excessive growths of algae and
macrophytes within the lake. Various methods that have been proposed in each of these
areas are summarized under the following topics.
· NUTRIENT REMOVAL FROM WASTE WATERS
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12. · DIVERSION OF WASTE WATERS
· DREDGING
· FLUSHING
· ZONING
· CHEMICAL CONTROL OF NUISANCE PLANT GROWTHS
· BIOLOGICAL CONTROL OF NUISANCE PLANT GROWTHS
· HARVESTING
· MIXING OF LAKES
· CONTROL OF AGRICULTURAL SOURCES OF NUTRIENTS
· URBAN DRAINAGE
· HYPOLIMNETIC WITHDRAWAL
· WATER-LEVEL MANAGEMENT
· IMMOBILIZATION OF NUTRIENTS
Question 6
Explain the sources of sea pollution:
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13. Domestic and Industrial waste
The quantity of polluted water mass is increasing for lack of refining and proper management,
and negligence, which is casting bad impact on the entire environment. Specialists expressed
apprehension of terrible situation of water pollution if such waste disposal could not be stopped.
Sources said houses have not specific management for keeping domestic garbage. Most of the
people do not use safety tank and throw the wastes into drains, lakes and rivers. Some dump
the wastes in low-laying places beside their houses which later get mixed with the river waters
flowing down canals or drains after rain. None does follow the rule of dropping the wastewater
into the river after refining and treatment in chemical method. As a result, the domestic wastes
are polluting water and environment and fishes of different species are on the way of extinction.
According to chemical analysis, domestic wastes contain poisonous Nitrate, Phosphate and
BOD. The wastes need treatment in a specific level after throwing into the river or canal.
Developed countries follow Sewerage Water Treatment Plant for waste treatment.
Waste water from manufacturing or chemical processes in industries contributes to water
pollution. Industrial waste water usually contains specific and readily identifiable chemical
compounds. .
The most polluting of them are the city sewage and industrial waste discharged into the rivers.
Industrial waste is defined as waste generated by manufacturing or industrial processes. The
types of industrial waste generated include cafeteria garbage, dirt and gravel, masonry and
concrete, scrap metals, trash, oil, solvents, chemicals, weed grass and trees, wood and scrap
lumber, and similar wastes. Industrial solid waste - which may be solid, liquid or gases held in
containers - is divided into hazardous and non-hazardous waste. Hazardous waste may result
from manufacturing or other industrial processes
Sludge Disposal
The solids that result from wastewater treatment may contain concentrated levels of
contaminants that were originally contained in the wastewater. A great deal of concern must be
directed to the proper disposal of these solids to protect environmental considerations.
Failure to do this may result in a mere shifting of the original pollutants in the waste stream to
the final disposal site where they may again become free to contaminate the environment.
A more reasonable approach to ultimate solids disposal is to view the sludge as a resource that
can be recycled or reused.
All the sewage sludge produced at a treatment plant must be disposed of ultimately. Treatment
processes may reduce its volume or so change its character as to facilitate its disposal, but still
leave a residue which in most cases must be removed from the plant site.
Oil Spill
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14. Effects of oil spills on marine life is endangered certain species of fish. Oil spill in large amounts
will cause sea surface coated by oil. Layer of oil on the sea surface will also kill algae, seaweed
and plankton which is the source of fish food. Extinction of a food source can also lead to the
extinction of fish.
Oil spill in the sea can also cause degradation of coral reefs. Coral reefs, especially in shallow
areas are covered by a layer of dispersed oil causes coral to die. Layer of oil covering the sea
surface also cause blocked sunlight and influence to the destruction of the ocean's coral.
The oil spill will destroy the natural habitat of marine life such as fish and other wildlife. Effects
of oil spills at sea to humans, affecting tourism and leisure area. The natural beauty of the coast
and the island will be affected because the spread of the oil spill. This resulted in tourism and
leisure activities in coastal areas is not possible. In addition, the oil spill spread to the islands will
affect water sports activities like diving on marine life has been destroyed in a shallow area of
the island.
Effects to the human is the lack of food supplies. When a lot of dead fish and possibly
extinction of certain species of fish will cause a lack of supply at the same time will affect the
supply of resources and food to the human protein. In addition, the effects of the spill spread far
to the coast will cause aquatic life that makes the mangrove forests as habitats are destroyed.
This will also cause disruption to the human food supply.
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