Design For Accessibility: Getting it right from the start
Chapter 4 - Environmental Pollution.pptx
1.
2. LECTURE 07 : Pollution- Definition & Explanation
Excessive discharge or addition of undesirable
substances or unwanted foreign matters into the
environment, there by adversely altering the natural
quality of environment and causing damage to
human, plants or animal life or unreasonably
interfering with the comfortable enjoyment of life or
conduct of business.
The adverse types of changes caused by the
misdeeds of man are called “environmental
pollution.”
Pollution is an unwanted, undesirable foreign matter
added to the environment. The pollutant may be
physical, chemical, bacteriological, suspended,
colloidal, dissolved, organic, inorganic, mineral salts,
toxic chemicals etc.
3. Pollution…
The air we breathe, the water we drink and the
places we live & work, might have been
contaminated with toxic substances or chemical
additives.
The adverse effects of chemical pollutants in
environment are not limited to ourselves, but may
be passed on to our future generation by way of
genetic mutations, birth defects, inherited diseases
and so on.
The future generation may blame our generation
for all these syndrome.
4. Causes of Pollution…
Man has spoiled and polluted the environment by:
Uncontrolled growth
Rapid industrialization
Rapid urbanization
exploitation of nature
5. Causes of pollution
Besides man, contributors to pollution are-
Volcanic eruptions,
Radio activities,
Strong wind & tsunami,
Forest fires, land slides,
Sand blowing etc.
Pollution has emerged as “ growing threat to the
orderliness of human life.”
6. AIR POLLUTION
Air pollution is a chemical, particulate matter, or
biological agent that modifies the natural
characteristics of the atmosphere.
Air pollution is said to exist if the level of harmful
gases, solids or liquids present in the atmosphere
are high enough to affect humans, other organisms,
buildings, monuments, etc.
Air pollution is measured in terms concentrated
suspended particulate matter (SPM) and nitrogen-
oxide & sulphur dioxide.
7. Source of Pollutants
Natural sources
sand/dust storms
volcanoes
forest fires
gases produced by decaying organisms
Human activity
11. Particulate matter
Solid particles generated by handling, crushing, grinding,
spraying and other operations are known as particulate
matter.
Particles size vary from 2.5 microns to 100 microns in the
atmosphere.
Small and light particles suspend whereas bigger sized
particles settle by their own weight.
Fine particles reach human lungs and cause respiratory
diseases.
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12. Classification of Pollutants
Primary Pollutant:
Primary pollutants are substances directly emitted from source; such
as ash from a volcanic eruption or the carbon monoxide gas from a
motor vehicle exhaust.
Secondary Pollutant:
Secondary pollutants not emitted directly. Rather, they form in the air
when primary pollutants react or interact. An important example of a
secondary pollutant is ground level ozone - one of the many
secondary pollutants that make up photochemical smog.
13. Major Primary Pollutants
Gases
Sulfur oxides (SOx) especially sulfur dioxide are emitted from
burning of coal and oil.
Nitrogen oxides (NOx) especially nitrogen dioxide are emitted from
high temperature combustion. Can be seen as the brown haze dome
above or plume downwind of cities.
Carbon monoxide. It is a product by incomplete combustion of fuel
such as natural gas, coal or wood. Vehicular exhaust is a major
source of carbon monoxide.
Carbon dioxide (CO2), emitted from combustion and respiration.
Volatile organic compounds (VOC), such as hydrocarbon fuel
vapors and solvents.
Chlorofluorocarbons (CFCs), harmful to the ozone layer emitted
from products currently banned from use.
Ammonia (NH3) emitted from agricultural processes.
14. Major Primary Pollutants
Particulate matter (PM), measured as smoke and dust.
Toxic metals, such as lead, cadmium and copper.
Odors, such as from garbage, sewage, and industrial
processes
Radioactive pollutants produced by nuclear
explosions and war explosives, and natural processes
such as radiation.
15. Secondary pollutants
Particulate matter formed from gaseous primary
pollutants and compounds in photochemical smog,
such as nitrogen dioxide.
Ground level ozone (O3) formed from NOx and VOCs.
Peroxyacetyl nitrate (PAN) similarly formed from
NOx and VOCs.
16. Indoor Pollutants
Harmful fumes from plastics, insulation and cleaners
Poor air circulation (especially in winter)
Cigarette smoke – deadliest of ALL indoor
pollutants
Microorganisms – bacteria and fungi
Radon (colorless, odorless, radioactive gas)
Radium in soil breaks down to form radon
Radon from soil is drawn into basement
18. LAND POLLUTION
Land pollution is the degradation of Earth's land surfaces
often caused by human activities and their misuse of land
resources. It occurs when waste is not disposed properly.
Disposal of urban and industrial wastes, exploitation of
minerals, and improper use of soil by inadequate
agricultural practices are a few factors. Urbanization and
industrialization are major causes of land pollution.
20. Solid waste :
Wastes from Agriculture: This comprises of waste matter produced by
crop, animal manure, and farm residues.
Wastes from Mining: Piles of coal refuse and heaps of slag.
Wastes from Industries: Industrial waste matter that can cause land
pollution can include paints, chemicals, and so on.
Solids from Sewage Treatment: Wastes that are left over after sewage has
been treated, biomass sludge, and settled solids.
Ashes: The residual matter that remains after solid fuels are burned.
Garbage: This comprises of waste matter from food that are decomposable
and other waste matter that are not decomposable such as glass, metal,
cloth, plastic, wood, paper, and so on.
21. Soil pollution :
It is caused by the presence of xenobiotic (human-
made) chemicals or other alteration in the natural soil
environment.
Caused due to :
underground storage tanks,
application of pesticides,
percolation of contaminated surface water to
subsurface strata
oil and fuel dumping
22. Harmful effects of land
pollution
Tonnes and tonnes of domestic wastes are dumped
every day. Since people do not follow proper
methods for the disposal of such wastes, it leaves the
places look dirty and makes them unhealthy.
Land pollution indirectly affects the respiratory
system of human beings. Breathing in polluted dust
or particle can result in a number of health problems
related to the respiratory system.
Skin problems are often diagnosed due to land
pollution. It is said that the improper disposal of
household wastes leads to allergic reactions on the
skin.
23. Land pollution has been found as one of the leading
causes for birth defects. Pregnant women living in
unhealthy and dirty environment can incur breathing
problems and a number of diseases, which may
affect the health of the baby as well.
Land pollution has serious effect on wildlife Flora,
which provides food and shelter to wildlife, are
destroyed.
Land pollution often disrupts the balance of Nature,
causing human fatalities.
24. Control measures :
Use the following guide for each product:
Glass: Bottles or jars can be reused or taken to a bottle bank for recycling.
Broken glass can be repeatedly recycled with no reduction in quality, saving
energy and raw materials.
Metals: Used aluminum and steel cans can be collected as scrap and
smelted for re-use.
Textiles: Old clothes may be given to charity shops or jumble sales or used
as rags. Some textiles can be re-used for blankets and cloths.
25. Plastics: As there are many types of plastics with different chemical
properties, it is not easy to recycle them. Most plastics do not degrade
and remain a nuisance in the environment for many years.
Biodegradable plastics have been developed but these are not suitable
for recycling.
Paper and Board: Most of this can be recycled or reused. Recycled
paper products are becoming widely available. You can help by buying
recycled paper products. Recycled tissues and toilet rolls should be
greyish in colour rather than brilliant white. Do not waste paper!
Vegetable Waste: A bucket with a lid makes a good container for
vegetable waste that can be regularly added to the compost heap for
use in the garden.
26. Clean up :
Excavate soil and take it to a disposal site away
from ready pathways for human or sensitive
ecosystem contact. Aeration of soils at the
contaminated site.
Thermal remediation by introduction of heat to
raise subsurface temperatures sufficiently high to
volatize chemical contaminants out of the soil for
vapor extraction.
Bioremediation, involving microbial digestion of
certain organic chemicals. Techniques used in
bioremediation include landfarming and
bioaugmentating soil biota.
27. MARINE POLLUTION
A direct or indirect introduction by humans of
substances or energy into marine environment.
Resulting in
Harm to living resources,
Hazards to human health,
Hindrances to marine activities including fishing,
Impairment of the quality of sea water and reduction of
amenities.
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28. Alien species
Source
Several thousand per
day transported in
ballast water; also
spread through canals
linking bodies of water
and fishery
enhancement projects
Effect
Out compete native
species and reduce
biological diversity.
Introduce new marine
diseases.
Associated with
increased incidence of
red tides and other algal
blooms.
Problem in major ports
29. Persistent Toxins (PCBs Heavy metals,
DDT etc.)
Source
Industrial discharge
Wastewater discharge
from cities
Pesticides from farms,
forests, home use etc.
Effect
Poison or cause disease
in coastal marine life ,
especially near major
cities or industry.
Contaminate sea food.
Fat soluble toxins that
bio magnify in
predators can cause
disease and
reproductive failure.
30. Oil
Source
From cars, heavy
machinery, industry &
other land based
sources;
Oil tanker operations
and other shipping
accidents at sea
Offshore oil drilling
Effect
Low level
contamination can kill
larvae and cause
disease in marine life.
Oil slicks kill marine
life, especially in
coastal habitats.
Tar balls from
coagulated oil litter
beaches and coastal
habitat.
31. Plastics
Source
Fishing nets
Cargo and cruise ships
Beach litter
Wastes from plastics
industry and landfills
Effect
Discarded fishing gear
continues to catch fish .
Other plastic debris
entangle marine life or
is mistaken for food.
Plastics litter beaches
and coasts and may
persist for 200 to 400
years.
32. Radioactive substances
Source
Discarded nuclear
submarine and military
waste
Atmospheric fallout
and industrial wastes
Effect
Can enter food chain
and cause disease in
marine life.
Concentrate in top are
predators and shell fish,
which are eaten by
people
33. Thermal
Source
Cooling water from
power plants and
industrial sites
Effect
Kill corals and other
temperature sensitive
sedentary species.
Displace other marine
life.
34. Marine Pollution Abatement
Identify load & type of pollutants and cut it at the
source.
Political commitment and enforce legislation.
Coastal and marine planning & management.
Create less waste.
Reduce/Eliminate the creation of pollutants through
increased efficiency in the use of raw materials,
energy, water etc.
Recycling, incineration.
Pretreatment before disposal to sea.
Use of equipment to reduce water content and
volume in the chemical process.
35. LECTURE 08 : Thermal Pollution
Thermal pollution is the degradation of water quality by any process
that changes ambient water temperature.
A common cause of thermal pollution is the use of water as a coolant
by power plants and industrial manufacturers. When water used as a
coolant is returned to the natural environment at a higher temperature,
the change in temperature decreases oxygen supply and affects
ecosystem composition.
Fish and other organisms adapted to particular temperature range can
be killed by an abrupt change in water temperature (either a rapid
increase or decrease) known as "thermal shock."
36. Thermal pollution may also increase the metabolic
rate of aquatic animals, as enzyme activity,
resulting in these organisms consuming more food
in a shorter time.
37. Nuclear pollution
Nuclear waste is the radioactive waste produced by
nuclear reactors, or left over from research projects,
medical uses, and the manufacture of nuclear
weapons.
38. Nuclear wastes
Two categories
high-level waste (HLW), and
low-level waste (LLW)
These are generally recognized, based on radioactivity,
source and hazard.
39. High Level Waste
High-level waste consists mainly of spent fuel rods from nuclear
reactors.
These power plants rely on nuclear fission to generate heat, and the
fuel is made into rods that can be moved in and out of the reactor
core to control the process. After a time, the rate of fission in a rod
will decrease to the point where it is no longer efficient, and the rod
will be removed. The removed rods are known as spent fuel rods and
are highly radioactive, containing a number of fission products.
These elements decay at different rates, and over time, the rods
become less radioactive, but will remain potentially dangerous for
many thousands of years.
40. Low Level wastes
It comes from a wide variety of sources. It consists of
materials that have come into contact with radioactive
substances, or which have become radioactive
themselves due to exposure to some forms of radiation,
as well as small quantities of radioisotopes from
research establishments and hospitals.
Examples are items of protective clothing worn by
staff who work with radioactive materials, and
syringes and needles used for the injection of
radioisotopes for medical purposes. It typically
remains potentially hazardous for between a few tens
and a few hundreds of years.
41. Disposal
High-level waste is generally stored on site at nuclear
power plants until a proper disposal site becomes
available.
During this initial storage period it is kept under at least
20 feet (6 meters) of water, which absorbs the radiation.
The favored option for long-term disposal is deep under
the ground, with the radioactive material encased in glass,
and carefully monitored.
Finding a suitable disposal site is, however, problematical,
as plans to store highly radioactive waste at any given
location tend to meet with fierce opposition. Spent fuel
rods may also be stored above ground in large metal and
concrete containers.
42. Another option for spent fuel rods is reprocessing.
After a nuclear fuel bundle has been removed from a
reactor, it still contains most of its original uranium, but
mixed with highly radioactive fission products.
This radioactive cocktail can be separated through a
process called nuclear reprocessing, which sorts the
elements in the spent fuel, and allows useful fuel to be
recovered and reused.
This process still leaves behind some highly radioactive
waste that needs to be disposed of, but the quantity is very
much smaller.
43. Low-level waste is stored in special containers that, where
necessary, have a degree of shielding appropriate to the
level, and type, of radioactivity.
Substances that emit alpha radiation do not require
shielding, as they are only dangerous if swallowed or
inhaled.
Gamma radiation and neutron emitters, however, require
significant shielding.
As with high-level waste, the materials are buried
underground, but usually relatively near the surface.
46. High levels of ionizing radiation kill cells and can
cause immediate life-threatening effects, while lower
levels can cause genetic damage and cancer.
To put things in perspective, however, nuclear waste is
not necessarily more dangerous than chemical poisons,
which are produced in much larger quantities. It has
been estimated that public exposure to cancer-causing
agents from coal-fired power stations is much greater
than from nuclear waste, due to chemicals, and natural
radioactive elements, released into the atmosphere
from the burning of coal.
47. Control of Radioactive Pollution:
The following preventive measures should be followed to control
radioactive pollution.
(i) Leakage of radioactive materials from nuclear reactors,
industries and laboratories using them should be totally
stopped.
(ii) Radioactive wastes disposal must be safe. They should be
changed into harmless form or stored in safe places so that
they can decay in a harmless manner. Radioactive wastes
only with very low radiation should be discharged into
sewerage.
(iii) Preventive measures should be taken so that natural radiation
level does not rise above the permissible limits.
(iv) Safety measures should be taken against accidents in nuclear
power plants.
50. Effects of Water Pollution
It damages the food chain. The toxins from water travel to the
body of human and animals.
The water pollution is responsible for spreading some deadly
diseases like cholera, typhoid, diarrhea, and other communicable
diseases. This is called microbial water pollution and the
pathogens are responsible for it.
Polluted water can also adversely affect the human heart and
kidneys. The toxins in the human body can create problems like
poor blood circulation, vomiting, skin lesions, damage to nervous
system and others.
Ground water level gets contaminated by carcinogenic elements
like lead, cadmium and others which when consumed with
drinking water increases the risk of having cancer.
Acid rain is another worry to water pollution. Sulfate particles
present in water creates problem for marine life. It pollutes the
water and also affects the food chain of marine life.
Lots of pollutants in water can be responsible for changing the
acidity, temperature, and conductivity of water.
52. Noise pollution
Noise pollution is the disturbing or excessive noise that may harm the
activity or balance of human or animal life. The source of most outdoor
noise worldwide is mainly caused by machines and transportation
systems, motor vehicles, aircraft and trains.
Outdoor noise is summarized by the word environmental noise. Poor urban
planning may give rise to noise pollution.
Indoor noise can be caused by machines, building activities, and music
performances, especially in some workplaces. There is no great difference
whether noise-induced hearing loss is brought about by outside (e.g. trains)
or inside (e.g. music) noise.
High noise levels can contribute to cardiovascular effects in humans, a rise
in blood pressure, and an increase in stress and vasoconstriction, and an
increased incidence of coronary artery disease. In animals, noise can
increase the risk of death by altering predator or prey detection and
avoidance, interfere with reproduction and navigation, and contribute to
permanent hearing loss.
54. Causes
Noise originates mostly from human.
The main causes are:
1. Transportation sector:- aircrafts, trains, trucks, tractors, cars, three-
wheelers, motorcycles etc , contribute maximum noise.
2. Industrial & construction machinery:-factory equipments,
generators, pile-drivers, pneumatic drills, road rollers etc, make lot
of noise.
3. Special events :- high volume sound speakers during festivals ,
marriage celebrations, pop-music, public meetings etc, create
unbearable noise.
55. Effects of noise
Noise is generally harmful and can create
serious health hazard.
Noise can lead to physiological & psychological
damage if the volume is very high or the
exposure is prolonged.
Vibrations of high pitches create permanent
hearing impairment.
Noise can also have other ill effects like heart
problem, pupil dilation or muscle contraction.
Migraine headache, nausea, dizziness, gastric
ulcers and constriction of blood vessels are
some of the other possible bad effects of noise.
56. Noise control
measures
Producing less noise is the best method of reducing type of
pollution. All machinery should be so designed that the noise
produced is minimum.
All the persons working in noisy areas should wear noise
shield like ear-plugs and such areas should be isolated by
having noise absorbing materials.
Proper lubrication and better maintenance of machines will
reduce noise while running.
By using:
silencers to control noise from automobiles, ducts, exhausts
etc. noise levels can be reduced;
glass wool or mineral wool covered with a sheet of perforated
metal plates , mechanical vibration isolation can be partly
achieved.
57. What is biomedical waste?
Biomedical waste is waste that is potentially infectious.
Biomedical waste may also include waste associated with
the generation of biomedical waste that visually appears
to be of medical or laboratory origin (e.g., packaging,
unused bandages, infusion kits, etc.), as well research
laboratory waste containing bio-molecules or organisms
that are restricted from environmental release.
As detailed below, discarded sharps are considered
biomedical waste whether they are contaminated or not,
due to the possibility of being contaminated with blood
and their propensity to cause injury when not properly
contained and disposed of. Biomedical waste is a type of
bio waste.
58. Sources of biomedical waste
Biomedical waste is generated from biological and
medical sources and activities, such as the diagnosis,
prevention, or treatment of diseases.
Common generators (or producers) of biomedical
waste include hospitals, health clinics, nursing
homes, medical research laboratories, offices
of physicians, dentists, and veterinarians, home health
care and funeral homes.
In healthcare facilities (i.e., hospitals, clinics, doctors
offices, veterinary hospitals and clinical laboratories),
waste with these characteristics may alternatively be
called medical or clinical waste.
59. Effects :
According to World Health Organization, hospital-associated
infections (HAI) affect approximately 5% of hospitalized
patients. The complexity of infectious healthcare waste problems and
the recent rise in the incidence of diseases such as AIDS, SARS and
Hepatitis B open up greater risk of contamination through
mishandling and unsafe disposal practices.
Inadequate waste management can cause environmental pollution,
growth and multiplication of vectors like insects, rodents and worms
and may lead to the transmission of diseases like typhoid, cholera,
hepatitis and AIDS through injuries from syringes and needles
contaminated with human.
In addition to health risks associated with poor management of
medical waste, consideration must also be given to the impact on
environment, especially to the risks of pollution of water, air and soil.
