What is an environment?

An environment can be defined as the physical, chemical and

biological world that surrounds us, as well as the complex of social and cultura l
conditions affecting an individual or community

Why study environmental literacy?

The environmental studies enlighten us, about the importance

of protection and conservation of our indiscriminate release of pollution into
the environment.

Environmental Science

Environmental Science is an interdisciplinary field that

involves both the physical sciences (physics, chemistry, biology, geology,
geography, resource technology and engineering) and the social sciences
(resource management and conservation, demography, economics, politics and
ethics). It encompasses the surrounding conditions that affect man and other
organisms. Natural and human resources are interdependent and the use or misus e
of one affects the other

Ecology

Ecology is the branch of biological science concerned with the

relationships and interactions between living organisms and their physical
surroundings or environment.

Living organisms and the environment with which they

exchange materials and energy together make up an ecosystem, which is
the basic unit of ecology. An ecosystem includes biotic components – the
living plants and animals and abiotic components – the air, water,
minerals, and soil that constitute the environment. A third and essential componen t
of most natural ecosystems is energy, usually in the form of sunlight.

Structure of Environment

Environment is both physical and biological. It includes

both living and nonliving
components.

(i) Physical Environment

The Physical Environment is classified into three broad

categories viz.

(i) Solid,

(ii) Liquid

(iii) Gas.

These represent the following spheres:

(i) The lithosphere (solid earth)

(ii) The hydrosphere (water component)

(iii) The atmosphere (gaseous component)

(ii) Biological Environment

The biological of the environment consists of:

(i) Plants (flora)

(ii) Animals (fauna).

Thus, the biotic environment further is divided into floral

environment and faunal environment. All the organisms work to form their social
groups and organizations at several levels. Thus, the social environment is
formed. In this social environment the organisms work to derive matter from the
physical environment for their sustenance and development. This process gives
birth to economic environment. Man claims to be most skilled and civilized of
all the organisms. This is the reason why his social organization is most
systematic.

Hazardous
Waste is a "solid waste" which because of its quantity,
concentration, or physical, chemical, or infectious characteristics may:

•
Pose a substantial present or potential hazard to human health or the
environment when improperly treated, stored or disposed of, or otherwise
mismanaged; or

•
Cause or contribute to an increase in mortality, or an increase in irreversibl e
or incapacitating illness.

A
"solid waste" is defined as any discarded material that is abandoned
by being disposed of, burned or incinerated, recycled or considered
"waste-like." A solid waste can physically be a solid, liquid,
semi-solid, or container of gaseous material. A waste is classified as a
hazardous waste if it has a hazardous characteristic listed below:

1.
Ignitable Hazardous Waste

a.
A liquid waste which has a flash point of
less than or equal to 140 degrees F (60 degrees C) as determined by an approve d
test method. Environmental Science www.AgriMoon.Com 178 2

b.
A non-liquid waste which, under standard
conditions, is capable of causing a fire through friction, absorption of
moisture or a spontaneous chemical change and when ignited, the waste burns s o
vigorously and persistently that it creates a hazard.

c.
An ignitable compressed gas or oxidizer.

2.
Corrosive Hazardous Waste

a.
An aqueous waste with a pH of less than or
equal to 2 or greater than or equal to 12.5 is considered to be a corrosi ve
hazardous waste.

b.
A liquid waste that corrodes steel at a
minimum rate of .25 inch per year as determined by an approved test method.

3.
Reactive Hazardous Waste

a.
A solid waste that is normally unstable,
reacts violently with water, or generates toxic gases when exposed to water or
other materials.

4.
Toxic Hazardous Waste

a.
A waste that contains certain substances
determined to be harmful at or in excess of the maximum concentration. Some o f
those substances include lead, arsenic, and mercury.

b.
Many things that are thrown out in the
rubbish, like some household batteries, car oil, or old paint, can contain
harmful chemicals that damage the environment. Find out how to dispose safel y
of domestic hazardous waste.

What
is hazardous waste? Waste is hazardous when it has properties that might mak e
it harmful to human health or the environment. The term 'hazardous' does not
always mean that such waste is immediately harmful, though some can be .
What
types of waste are hazardous? Domestic wastes that may be hazardous include:

•
Asbestos, Pesticides, Fluorescent tubes, Oils, some paints, some household an d
car batteries, Discarded electrical equipment such as TVs and computer
monitors, fridges and freezers

How
to dispose of hazardous waste

Disposal
methods:

Incineration is a waste treatment technology that involves the

combustion of organic materials and / or substances. Incineration and other
high temperature waste treatment systems are described as "thermal
treatment". Incineration of waste materials converts the waste into
incinerator bottom ash, flue gases, particulates, and heat, which can in tur n
be used to generate electric power. The flue gases are cleaned of pollutants
before they are dispersed in the atmosphere

Landfills, the volume of the

uncompressed garbage can be reduced by approximately 70% with the use of a
stationary steel compressor, albeit with a significant energy cost. In many
countries simpler waste compaction is a common practice for compaction at
landfills

Waste
combustion
is particularly popular in countries such as Japan where land is a scarce
resource. Denmark and Sweden have been leaders in using the energy generated
from incineration for more than a century, in localized combined heat and power
facilities supporting district heating schemes.

Pyrolysis is the chemical

decomposition of condensed substances by heating that occurs spontaneously a t
high enough temperatures. The word is coined from the Greek derived elements
pyro "fire" and lysys "decomposition". Pyrolysis is a
special case of thermolysis, and is most commonly used for organic materials,
being then one of the processes involved in charring. The pyrolysis of wood,
which starts above 300 °C, occurs for example in fires or when vegetation comes
into contact with lava in volcanic eruptions. In general, pyrolysis of organic
substances produces gas and liquid products and leaves a solid residue richer
in carbon content. Extreme pyrolysis, which leaves mostly carbon as the
residue, is called carbonization.
Pollution

Any undesirable change in the physical, chemical and

biological properties of air, water and soil that adversely affects the life i s
called pollution. The pollution may be due to human activities or natural
ecosystems. Natural pollution contaminates the air by storms, forest fire ,
volcanoes and natural processes (methane from marshy lands). Manmade pollutants
threaten the integrity of the nature.

Types of pollution

The various types of pollution are classified based on the

environment, based on sources of pollutant or nature of pollutants. Based on
environment they are classified as Soil pollution, water pollution, and air
pollution. Based on sources of pollutants, they are classified as automobil e
pollution, agricultural pollution and industrial pollution (tanneries,
distilleries, nuclear power plants, chemical industries, etc.). Based on natur e
of pollutants, pollution is classified as pesticide pollution, plastic pollution,
heavy metal pollution, radiation pollution, oil pollution, sewage pollution,
noise pollution, etc.

Pollutants

Any substance present in concentrations high enough to cause

adverse effect in the environment/living organisms. Substances that cause
pollution is also called pollutants.

Environment Protection Act, 1986 (EPA, 1986) defines

pollutant, as any solid, liquid or gaseous substance present in such a
concentration as may be, or tend to be, injurious to environment.

Air pollution, major air pollutants, source, effect and

control measures
Air is necessary for the survival of all higher forms of life
on earth. On an average, a person needs at least 30 lb of air every day to
live, but only about 3 lb of water and 1.5 lb of food. A person can live about
5 weeks without food and about 5 days without water, but only 5 minutes withou t
air. Naturally, everyone likes to breathe fresh, clean air. But the atmosphere,
that invisible yet essential ocean of different gases called air, is as
susceptible to pollution from human activities as are water and land environments .

Any undesirable change in the physical, chemical and

biological properties of air that adversely affects the life is called air
pollution. Air pollution may be simply defined as the presence of certain
substances in the air in high enough concentrations and for long enough
duration to cause undesirable effects. “Certain substances” may be any gas, liqui d
or solid, although certain specific substances are considered significant
pollutants because of very large emission rates or harmful and unwanted
effects. “Long enough durations” can be anywhere from a few hours to several
days or weeks; on a global scale, durations of months and years are of concern.

Air pollution

Assignment

Identify major air pollutants their sources and effects on

the environment

1. Ozone. A gas that can be found in two places. Near

the ground (the troposphere), it is a major part of smog. The harmful ozone i n
the lower atmosphere should not be confused with the protective layer of ozone
in the upper atmosphere (stratosphere), which screens out harmful ultraviolet
rays.

Source of ozone

Ozone is not created directly, but is formed when nitrogen

oxides and volatile organic compounds mix in sunlight. That is why ozone is
mostly found in the summer. Nitrogen oxides come from burning gasoline, coal ,
or other fossil fuels. There are many types of volatile organic compounds, and the y
come from sources ranging from factories to trees.
Effect

Ozone near the ground can cause a number of health problems.

Ozone can lead to more frequent asthma attacks in people who have asthma and
can cause sore throats, coughs, and breathing difficulty. It may even lead to
premature death. Ozone can also hurt plants and crops.

2. Carbon monoxide. A gas that comes from the burning

of fossil fuels, mostly in cars. It cannot be seen or smelled.

Sources

Carbon monoxide is released when engines burn fossil fuels. Emissions

are higher when engines are not tuned properly, and when fuel is not completely
burned. Cars emit a lot of the carbon monoxide found outdoors. Furnaces and heater s
in the home can emit high concentrations of carbon monoxide, too, if they are
not properly maintained.

Effects

Carbon monoxide makes it hard for body parts to get the

oxygen they need to run correctly. Exposure to carbon monoxide makes people
feel dizzy and tired and gives them headaches. In high concentrations it is fatal .
Elderly people with heart disease are hospitalized more often when they are
exposed to higher amounts of carbon monoxide.

3. Nitrogen dioxide.

4. Particulate matter. Solid or liquid matter that is

suspended in the air. To remain in the air, particles usually must be less than
0.1-mm wide and can be as small as 0.00005 mm.

5. Lead. A blue-gray metal that is very toxic and is

found in a number of forms and locations.

Effects of ambient air pollution

Air pollution is known to have many adverse effects,
including those on human health, buildings and other exposed materials,
vegetation, agricultural crops, animals, aquatic and terrestrial ecosystems,
and the climate of earth as a whole.

Health effects

Perhaps the most important effect of air pollution is the

harm it causes to human health. Generally, air pollution is most harmful to the
very old and the very young. Many elderly people may already suffer from som e
form of heart or lung disease, and their weakened condition can make them ver y
susceptible to additional harm from air pollution. The sensitive lungs of new
born infants are also susceptible to harm from dirty air. But it is not jus t
the elderly or the very young who suffer; healthy people of all ages can be
adversely affected by high levels of air pollutants. Major health effects are categorized
as being acute, chronic, or temporary.

There is much evidence linking lung cancer to air pollution,

although the actual cause-and – effect relationship is still unknown. Typical
effects of sulfur dioxide, oxides of nitrogen, and ozone include eye and throat
irritation, coughing and chest pain. Nitrogen dioxide is known to cause
pulmonary edema, an accumulation of excessive fluids in the lungs. Ozone, a
highly irritating gas, produces pulmonary congestion; symptoms of ozone
exposure may include dry throat, headache, disorientation, and altered breathing
patterns.

Air Pollution control strategies

1.
There are several approaches or strategies
for air pollution control. The most effective control would be to
prevent the pollution from occurring in the first place. Complete
source shutdown would accomplish this, but shutdown is only practical under
emergency
conditions, and even then, it causes economic loss. Nevertheless,
state public health officials can force industries to stop operations and can
curtail highway traffic if an air pollution episode is imminent or
occurring.

2.
Another option for air pollution control is
source location in order to minimize the adverse impacts in a particular
locality. An important approach for air pollution control is to
encourage industries to make fuel substitutions or process changes. For
example, making more use of solar, hydroelectric, and geothermal energ y
would eliminate much of the pollution caused by fossil fuel
combustion at power generating plants. Nuclear power would
do the same, but other problems related to high level radioactive waste
disposal and safety remain to be solved.

3.
Fuel substitutions are also effective in
reducing pollution from mobile sources. For example, the use of
reformulated gasoline or alternative fuels such as liquefied petroleum
gas, compressed natural gas, or methanol for highway vehicles would help t o
clear
the air. The use of correct operation and maintenance practices is important
for minimizing air pollution and should not be overlooked as an
effective control strategy.

4.
Air pollution control strategies can be
divided into two categories, the control of particulate emissions and the
control of gaseous emissions. There are many kinds of equipment
which can be used to reduce particulate emissions. Physical separation of the
particulates
from the air using settling chambers, cyclone collectors, impingers,
wet scrubbers, electrostatic precipitators, and filtration devices,
are some processes that are typically employed. Gaseous emissions are
controlled by similar devices and typically can be used in conjunction with
particulate control options, such as scrubbers, adsorption systems,
condensers, flares, and incinerators.

5.
Scrubbers utilize the phenomena of
adsorption to remove gaseous pollutants from the air stream. There is a wid e
variety of scrubbers available for use, including spray towers,
packed towers, and venturi scrubbers. A wide variety of solutions can be used
in this process as absorbing agents. Lime, magnesium oxide, and
sodium hydroxide are typically used.

6.
Adsorption can also be used to control
gaseous emissions. Activated carbon is commonly used as an adsorbent in
configurations such as fixed bed and fluidized bed absorbers.
Another means of controlling both particulate and gaseous air pollutant emissio n
can be accomplished by modifying the process which generates these pollutants .

7.
For example, modifications to process
equipment or raw materials can provide effective source reduction. Also, employing
fuel cleaning methods such as desulfurization and increasing
fuel-burning efficiency can lessen air emissions.

Global Air Pollution

Air pollution problems are not necessarily confined to a

local or regional scale. Atmospheric circulation can transport certain
pollutants far away from their point of origin, expanding air pollution to
continental or global scales; it can truly be said that air quality problem s
know no international boundaries. Some air pollutants are known to be associated
with changes in earth’s climate, requiring consideration of governmental actions
to limit their impacts. Two important air pollution problems that are generall y
considered worldwide in scope are global warming and depletion of stratospheric
ozone.
Water
pollution

Water
like air, is an indispensable and one of the most precious of natural resource s
on this planet. Most of our water bodies such as ponds, lakes, streams and
river have become polluted as a consequence of increasing industrialization,
urbanization and other development activities.

In
general terms, water is considered to be polluted when it contains enough
foreign material to render it unfit for specific beneficial use, such as for
drinking, recreation, or fish propagation. Actually, human activity is the
cause of the poor water quality and cause water pollution. The water pollution
is defined as addition of any substances that alter the physical and chemical
characteristics of water in any way which interferes with its use for legitimate
purposes.

Classification
of water pollutants

To
understand the effects of water pollution and the technology applied in its
control, it is useful to classify pollutants into various groups or categories.

First, a pollutant can be classified according

to the nature of its origin as either a point source or a
dispersed source pollutant (non-point source).

A point
source pollutant is one that reaches the water from a pipe, channel or any
other confined and localized source. The most common example of a point source
of pollutants is a pipe that discharges sewage into a stream or river

A dispersed
or non-point source is a broad, unconfined area from which pollutants enter
a body of water. Surface runoff from agricultural areas carries silt,
fertilizers, pesticides, and animal wastes into streams, but not at only one
particular point. These materials can enter the water all along a stream as i t
flows through the area.

Control
of water pollutants

Point
source pollutants are easier to deal with while pollutants from dispersed
sources are much more difficult to control. Many people think that sewage is
the primary culprit in water pollution problems, but dispersed sources cause a
significant fraction of the water pollution. The most effective way to control
the dispersed sources is to set appropriate restrictions on land use

Sources
and impacts of water pollution There are many causes for water pollution but
two general categories exist:

1.
Direct sources
include effluent outfalls from factories, refineries, waste treatment plants
etc. that emits fluids of varying quality directly into urban water supplies.

2.
Indirect sources
include contaminants that enter the water supply from soils/groundwater systems
and from the atmosphere via rain water. Soils and groundwaters contain the
residue of human agricultural practices (fertilizers, pesticides, etc.) and
improperly disposed of industrial wastes. Atmospheric contaminants are als o
derived from human practices (such as gaseous emissions from automobiles,
factories) Contaminants can be broadly classified into organic, inorganic,
radioactive and acid/base

Assignment: Discuss various ways for prevention and control of water pollution (15
marks)
To be submitted by 15th October 2024 as a word document
to wanguitheefarmer@gmail.com not later than 5pm
clearly indicate your name, admission number and class in your document

Soil
pollution, source, effect and control measures

Soil
is the loose and unconsolidated outer layer of earth’s crust that is powdery i n
nature and made up of small particles of different sizes. Soil ecosystem
includes inorganic and organic constituents, and the microbial groups. Soi l
microorganisms are the active agents in the decomposition of plant and animal
solid wastes and said to be nature’s garbage disposal system. The soil microbes
keep our planet earth free of unwanted waste materials and recycle the elements
(C, N, and P) through mineralization.

An
undesirable change in the physical, chemical or biological characterization of
soil may harmfully affect the life or create a potential health hazard of any
living organisms.

Soil
pollution could result from a whole range of situations, and can have lasting
effects on all types of ecosystems and human health. Soil may become
contaminated through dry deposition or by toxins becoming integrated into in
the ground water.

Soil
Pollutants

•
Acid rain: Oxides of Sulphur and nitrogen • Heavy metals: Lead, Cadmium,
Chromium, Copper, Nickel, Arsenic, Titanium, Mercury, Selenium etc. •
Industrial wastes • Sewage • Agricultural wastes: Fertilizers, Pesticides,
Herbicides, Other Chemicals • Volcanoes • Oil, grease and other petroleum product s
• Asbestos
Effects
of soil pollutants

•
Affects soil health and productivity

•
Affects plant and animals

•
Affects soil microbes

•
Ground water contamination through seepage

•
Affects human health

•
Causes biomagnification etc.

Soil
Remediation process

1.
Phytoremediation- The
process of recovery of hazardous substances from soil or ground water
contaminated with municipal or industrial wastes etc. by using plants is called
phytoremediation. Among vascular plants, some aquatic weeds such as
species of Salvia, Lemna, Azolla, sedges and tree species are known to tolerate
and uptake heavy metals. Bamboo can accumulate Zn, Cd, Ni and Pb (lead). Flower
crops could be an effective method of remediating soil polluted due to disposal
of tannery effluent.

2.
Biological transformation
of heavy metals is an important detoxification mechanism that can occur in man y
habitats and can be carried out by a variety of microorganisms especially
bacteria and fungi. As a result of biological action, metals undergo changes i n
valency and or conversion into organometallic compounds.

3.
Bioventing:
It is the In-situ method of bio remediation in which air is supplied to an unsaturated
soil zone through installation of wells connected to associated pumps and
blowers which draw a vacuum on the soil.

4.
Air spraying:
It involves the injection of air into the saturated zone of a contaminated
soil.

Noise
pollution, source, effect and control measures

Unwanted
sound that causes discomfort to the listener is called noise. Wrong sound in
wrong place at wrong time is also called noise

·
Modern mechanization and technological innovation have
greatly increased the source of noise forced to consider it a major component
of environmental pollution.

·
Formerly it was limited with the industrial environment only
where heavy machines used to work round the clock. But with growing population
heavy traffic and urban crowd and electrical entertainment it has become new
irritant.

Sources of noise

1. Natural – Thunder

2. Man made – Industrial and

Non-industrial

Industrial
source: Industries of various kinds such as textile, iron, steel, utensils,
automobiles, fertilizers, paper, ceramics and thermal power stations are the
major contribution of noise. Machines in connection with threshing, grinding,
drilling, bunching, weaving, boiler making, forging, pressing and blasting
operations.

Non-industrial source: (a) Domestic noise (b) Loud speaker (c) Construction
work (d)Traffic (e) Crowded markets (f) Theatres (g) Religious function
(h)Cultural festivals (i) Trains (j) Air craft’s (k) Projection of satellites (l )
Atomic explosions.

Effect
of noise pollution

Effect
on human beings

Affects physiological and mental health

Reduces job efficiency

Reduces enjoyment of life at home.

Prolonged exposure to noise beyond 90 dB may

cause hearing loss.

In some cases, it causes auditory fatigue,

nervousness, irritability, increased blood pressure, cardio-vascular,
respiratory, glandular, deafness and neurological disorders. Physiological disorder :
Neurosis, anxiety, insomnia, hypertension

Effects
on wildlife:

Decline
is migratory birds to a habitat if it becomes noisy animals become dull and
inactive.

Effects
on non-living things:

High
intensity of noise, such as vibrations emanating from heavy machineries cause
shattering of window glasses, loosen the plaster of house walls, cracks in
walls.

Sometime even cause the shattering of the

foundation of the building.

Noise may also cause depreciation of the

residential property located nearby air path, highways, industrial areas and
other noise prone areas.

Control
of noise pollution

1.
Control of noise at source

·
Designing and fabricating silencing devices and then use in
air craft, motor cycles, industrial machines and home appliances.

·
Segregating the noisy equipment.

·
Introducing less noisy machines in plan of noisy areas.

·
Conducting noisy operations in open spaces far away from
residential zones.

·
Setting up industries 5 km away from residential zones

2.
Control of transmission: This is achieved by covering the room walls with
sound absorbing materials constrained layer damping technique.

3.
Protection of exposed person: Using weaving devices such
as ear plugs and ear muffs.

4.
Creation of vegetation and buffer zones: Growing of noise absorbing
plants like Ashoka, Banyan, Neem, Legume, Tamarind, Coconut etc. in the road
side and in front of buildings.

5.
Environmental education and awareness: People may be made aware
of health hazards of noise pollution through newspapers, Television, Articles,
Radio, News reels in cinema halls etc.

6.
Legislation: Strict laws and enforcement; Appointing Noise Inspector
Environmental
contaminants are chemicals that are present in the environment in which th e
food is grown, harvested, transported, stored, packaged, processed, and
consumed. The physical contact of the food with its environment results in its
contamination.

Possible
sources of contamination are:

1.
Air: radionuclides, polycyclic aromatic
hydrocarbons

2.
Water: arsenic, mercury.

3.
Soil: cadmium, nitrates, perchlorates.
Polychlorinated biphenyls (PCB), dioxins, and polybrominated diphenyl ethers
(PBDE) are ubiquitous chemicals, which are present in air, water, soil, and the
entire biosphere.

4.
Packaging materials: antimony, tin, lead,
perfluorooctanoic acid (PFOA), semicarbazide, benzophenone,
isopropylthioxanthone (ITX), bisphenol A.

5.
Processing/cooking equipment: copper, or
other metal chips, lubricants, cleaning and sanitizing agents. Naturally
occurring toxins: mycotoxins, phytohaemagglutinin, pyrrolizidine alkaloids,
grayanotoxin, mushroom toxins, scombrotoxin (histamine), ciguatera, shellfish
toxins, tetrodotoxin, among many others.

6.
Banned pesticides, carcinogens There are
many cases of banned pesticides or carcinogens found in foods.

7.
Hair in food- Many people consider hair in
food to be particularly unpleasant, however there are certain risks to be
considered such as choking and repulsion induced vomiting

8.
Processing contaminants are generated
during the processing of foods (e.g. heating, fermentation). They are absent i n
the raw materials, and are formed by chemical reactions between natural and/o r
added food constituents during processing

How
to control and ensure no contamination

Safety
and regulation -Acceptable Daily Intake (ADI) levels and tolerable concentrations of
contaminants in individual foods are determined on the basis of the "No
Observed Adverse Effect Level" (NOAEL) in animal experiments, by using a
safety factor (usually 100). The maximum concentrations of contaminants allowe d
by legislation are often well below toxicological tolerance levels, because
such levels can often be reasonably achieved by using good agricultural and
manufacturing practices. The establishment of ADIs for certain emerging food
contaminants is currently an active area of research and regulatory debate .

A preservative
is a natural or synthetic chemical that is added to products such as foods,
pharmaceuticals, paints, biological samples, wood, etc. to prevent
decomposition by microbial growth or by undesirable chemical changes.