WASTES & POLLUTION
DR. AYESHA HUMAYUN
ASSISTANT PROFESSOR &
PUBLIC HEALTH CONSULTANT
COMMUNITY HEALTH SCIENCES
FMH, COLLEGE OF MEDICINE & DENTISTRY,
SHADMAN, LAHORE, PAKISTAN.
I had been teaching and
training doctors in the field
of Public Health for more
than five years.
The topic of wastes and pollution is very
vast but I have tried to cover it in one
lecture. Details of each sub topic will be
covered in my next lectures.
LEARNING OBJECTIVES:
1. To conceptualize the natural and
human sources of wastes and
pollution.
2. To understand the hazards of waste
production
3. To understand the importance of
waste management
PERFORMANCE OBJECTIVES:
By the end of the lecture the students
should be able to:
1. View environmental impact of the
man made and natural sources of
waste production.
2. Correlate different options of waste
management with practical life.
As human beings, we are part of
the environment.
The way in which we interact
with our environment influences
the quality of our lives.
WASTE is the by- product of
human activities.
It may be in the form of solid, liquid
or gases. It may be Risk or Non- Risk
waste.
TYPES OF WASTES
1. Human body wastes: urine and
feces
2. Excess materials and foods: trash
and garbage
3. Vegetation wastes: grass clippings
and tree branches
4. Construction and manufacturing
wastes (including excess
heat and noise).
5. Transportation wastes: carbon
monoxide, nitrous oxides,
hydrocarbons, other gaseous
pollutants and used motor oil
6. Energy production wastes: mining
wastes, electrical power (combustion
of coal), nuclear power (radioactive)
wastes and weapons production
(radioactive) wastes
Man- Made Factors that contribute to
a worsening of environmental hazards
are urbanization, industrialization,
population growth, and the production of
disposable products and containers.
Natural factors causing environmental
hazards
can be physical such as volcanic activity;
severe weather; biological, such as
epidemic diseases; psychological or
social.
I- SOLID WASTES
include garbage, trash, yard waste,
wood, metal, stone, and glass scrapes
from domestic or industrial
sources.(non- Hazardous)
1. Sources of solid waste
a. Agriculture
b. Mining
c. Industry
d. Municipal sources
Solid waste management
is the collection, transportation,
and disposal of solid waste.
Collection
is the gathering and transporting of
solid wastes from the point of origin
to the point of disposal.
Disposal
is the final disposition of solid
wastes in such a way as to prevent them from
harming the environment or human health.
i. Sanitary landfills are sites or locations
judged suitable for the in-ground disposal of
solid wastes.
ii. Incineration is the burning or combustion of
solid wastes.
iii. Recycling (resource recovery) is the
collection and reprocessing of a solid waste
"resource" so it can be reused.
iv. Source reduction is the reduction in, or
elimination of use of materials that could
become solid waste.
II- HAZARDOUS WASTES
are those that are dangerous to human health
or to the environment.
Hazardous wastes are solid wastes that
can:
a. Cause or significantly contribute to an
increase in mortality or an increase in serious
irreversible, or incapacitating, reversible
illness.
b. Pose a substantial present or potential
hazard to human health or the environment
when improperly treated, stored, transported,
or disposed of, or otherwise managed.
Hazardous waste management
a. Secured landfills are the least expensive
method of hazardous waste disposal when they
are:
i. Carefully designed and located
ii. Monitored for leakage
b. Deep well injection is the pumping of liquid
hazardous waste into wells below the aquifer.
c. Incineration of hazardous waste is the
controlled combustion of hazardous waste.
d. Hazardous waste recycling is the process of
reusing hazardous waste to produce a usable
product, a process sometimes accomplished
through "waste exchanges" in Europe.
e. Neutralization of hazardous waste is the
process of detoxifying the waste so it is less
toxic, corrosive, or otherwise hazardous.
f. Source reduction is the alteration of
manufacturing processes to reduce or
eliminate the generation of hazardous waste.
3.Hazardous waste cleanup
a. Since the disposal of hazardous waste was
unregulated before 1976, there exist many
hazardous waste sites around the United
States.
b. The "Superfund" Law (CERCLA) was
passed in 1980 and amended in 1986 to clean
up such sites.
Air pollution
is the contamination of the air by substances
in amounts great enough to interfere with
comfort, safety and health.
1. Air pollution can arise from both natural
and human sources.
2. Air pollution can occur indoors as well as
outdoors.
3. Major sources of outdoor air pollution
include:
a. Transportation
b. Electric power plants fueled by oil and coal
c. Industry
1. Air pollutants of greatest concern are
called "criterion pollutants".
2. National standards for allowable levels
of criteria pollutants are known as the
National Ambient Air Quality Standards.
3. The Pollutant Standard Index is a scale
that relates pollution concentrations to
health effects.
4. Special concerns with outdoor air
include: Acid rain, destruction of the
ozone layer, global warming, and
photochemical smog.
Acid rain
refers to the deposition on the
earth surface of sulfuric and
nitrous acids removed from the
atmosphere during the formation
of rain droplets.
i. Acid rain can damage vegetation
and human structures.
ii. Acid rain often falls on areas
distant to the pollution source.
b. The ozone layer
surrounds the earth and filters out
a significant portion of the sun's
ultraviolet radiation.
i. Chloro-fluorocarbons, a group of
industrial chemicals, is believed to
be partly responsible for depleting
the ozone layer.
ii. Industrialized countries have
agreed to stop or reduce the use
of CFCs.
c. Global warming
is the gradual increase in the earth's
temperature.
i. There is still controversy among
scientists as to whether global
warming is actually occurring.
ii. It may be that the building up of
greenhouse gases will trap heat
radiated by the earth' s surface and
cause global warming.
d. Photochemical smog
is a secondary air pollutant created
when primary pollutants react with
sunlight and atmospheric oxygen.
i. Denver, Los Angeles, Phoenix and
Salt Lake City all experience
photochemical smog.
ii. Thermal inversions, the trapping of
cooler air under warmer air, worsen
the effects of photochemical smog.
e. Protection of outdoor air
through regulation dates to 1815 in
Pittsburgh, Pennsylvania.
i. Air quality in the U. S. deteriorated
until the Clean Air Act was passed in
1963.
ii. The first Earth Day was celebrated
in 1970, the same year that the
Environmental Protection Agency was
established and important
amendments to the Clean Air Act were
passed.
f. Indoor air
i. As outdoor air has become cleaner, there has
been more concern about the quality of indoor
air.
ii. Indoor air pollutants are gases or particulate
matter inside buildings that interfere with human
comfort, safety and health.
a) Asbestos
b) Biogenic pollutants
c) Combustion by-products
d) Formaldehyde
e) Radon
f) Environmental tobacco smoke
g) Volatile organic compounds
Protection of indoor air quality
can be achieved by changes in policy
and/or individual behavior.
a) Policy to regulate indoor air quality
is generally aimed at smoking.
b) Individual behavioral changes
represent an important way to
improve indoor air quality.
D. Water and Its Pollution
1. Sources of fresh water include surface water
and ground water.
a. Surface water includes water from lakes,
reservoirs, rivers and streams.
b. Ground water lies in aquifers many feet
below the earth's surface.
c. Salt water must be desalinized before use.
2. Treatment of water for domestic use
a. Municipal water treatment plants provide
water that is chemically and biologically safe
for human consumption.
b. Treatment of surface water includes several
cleaning steps and then disinfection.
3. Sources of water pollution
a. Point source pollution occurs at a single
point, for example and industrial plant.
b. Non-point source pollution is all other
pollution in water.
4. Types of water pollutants
a. Biological pollutants are living agents
i. Viruses, bacterial and other parasites
ii. Overgrowth of plant life in water source
b. Toxic pollutants
i. Inorganic chemicals such as lead, copper, etc.
ii. Radioactive pollution
iii. Synthetic organic compounds such as
pesticides
5. Water Related Issues
a. Water quantity
i. Overall there is ample freshwater in
America.
ii. Certain areas have experienced
droughts resulting in water shortages.
b. Water quality in the United States is
threatened by four conditions
i. Population growth
ii. Growth of the chemical industry
iii. Environmental mismanagement,
including irresponsible waste disposal
iv. Reckless land use practices
6. Strategies to insure safe water
a. Policy: federal legislation
i. The Clean Water Act had as its goal to make
U. S. waterways swimmable and fishable.
ii. The Safe Drinking Water Act had as its goal
to ensure safety of public drinking water.
b. Municipal waste water treatment
i. Primary treatment
ii. Secondary treatment
iii. Tertiary treatment
b. Septic systems
c. Conservation of water
E. Radiation
1. Sources of Radiation
a. Naturally occurring radiation
b. Human made radiation
2. Policy and nuclear radiation
F. Noise Pollution can be defined as
excess noise.
1. What is noise and how is it measured?
a. Noise is the result of energy conversion
to vibrations that are detected by
instruments and our ears.
b. Noise has various qualities such as
frequency and amplitude.
2. Approaches to noise abatement
a. Policy
i. Most policies that deal with noise are local
policies.
ii. Noise Control Act of 1972 was the first
federal law on noise control and dealt with
consumer products only.
b. Educational programs aimed at reducing
noise are unproven in their effectiveness.
c. Environmental modifications offer
solutions for reducing noise in some
situations.