Environmental health: air pollution

1. Environment & Health
Dr. Dalia El-Shafei
Ass.Prof of Community Medicine

2. ∗ Environment: any things surrounding us & can
affect health
∗ Environmental sanitation: properties &
requisites of clean environment.
∗ Environmental health: protection of human
health from hazards of unsanitary environment.
Definitions

4. Components of environmental sanitation

6. Proper planning of a new district or city or village
before construction
1- Town planning

7. ∗ New city must be classified into industrial, commercial
& residential zones.
∗ Wide streets, parks, green areas
∗ Available health services, fire extinguishing center,
transportation methods.
Basic requirements of planning are:

8. 2-Sanitary housing

9. 2- Sanitary housing
The health conditions that must be fulfilled
in any building.

10. Basic requirements of sanitary building:
1. Far from industrial areas, volcanoes or river floods- quit
place-clean surroundings
2. Made of safe, strong materials & proper foundations to
overcome rains, destruction
3. Privacy: separate house for each family & adequate rooms
in relation to individuals.
4. Adequate ventilation.
5. Adequate lighting.
6. Sanitary water supply.
7. Sanitary waste disposal.
8. Safety measures for prevention of accidents: good
lighting, safe furniture.

11. Question
1- State the criteria for choosing new house?
2- What are the priorities for selecting healthy house
with limited resources?

12. Slums
∗ Narrow streets, densely populated with poor housing &
unsanitary environment.

13. ∗ Increased rate of infection & death
∗ Increased accidents as fire, falls
∗ Increased social problems: addiction, crime
∗ Psychological problems due to lack of privacy &
crowdedness.
Hazards of Slum areas & Unsanitary
housing

14. How can we solve the health problems of slum
areas?
∗ Build new towns in distant areas with all
services
∗ Low renting of houses
∗ Prevent illegal construction of houses without
sanitary water or waste disposal.
∗ Increase working chances to increase
socioeconomic status.

15. Urbanization
Is the process of migration of people from rural to urban areas
for better opportunities of jobs, services & recreation.
Health hazards of urbanization:
1- Over crowdedness, leading to more lowering of socio economic
standard & bad sanitary conditions. (slum areas)
2- Spread of communicable diseases “TB, skin diseases, parasites,
respiratory infections”.
3- Social problems, quarrel, homicides
4- Delinquency, drug abuse, more crimes.

16. ∗ Ventilation: providing and or removing air from a confined
place by natural or artificial means.
Types of ventilation
∗ Natural ventilation
∗ artificial ventilation
3- Ventilation & air sanitation

17. Natural ventilation: windows, other openings of
adequate area & distribution to introduce fresh air.

18. ∗ Artificial ventilation: air condition & fans

19. Quality & Quantity of components
of air that can affect health.
Air Sanitation

20. Causes of unsanitary air

21. 1. Wind & air movements:
dilution of substances
2. Plants & trees: give O2 &
absorb CO2 (photosynthesis)
3. Rains: dissolve gases & fumes,
settle down suspended dust.
Natural correction of unsanitary air

22. Hazards of
cHemical cHanges
in air
(air pollution)

23. Components of air:

26. Introduction of one or more pollutants in the
atmosphere.
Or: presence of unwanted material in air in
sufficient amount & for sufficient time to
interfere with comfort of man, or to affect his
health.
Def. of air pollution:

28. 1- Respiration of man, animals & plants (O2 decreases, CO2, temp. &
humidity increase, & expired air may contain microorganisms).
2- Combustion of fuel by transportation vehicles or machines.
3- Fermentation of organic materials in refuse (CO2 increases & foul
smell is produced).
4- Volcanoes & forest fires (fumes & different gases of melted
metals, CO2, CO, ashes & smog after burn of trees).
5- Dust from streets, homes, & agriculture wastes.
6- EMWs from TVs & mobile telephones.
7- Excessive noise especially in cities.
8- Industrial wastes as dust, gases, fumes, & vapors.
Sources of air pollution:

30. They are present in the form of aerosols (solid particles
or liquid droplets suspended in a gaseous medium) such
as dust, pollens, smoke.
Sources: Combustion, industry.
Hazards: Reduce visibility & cause respiratory problems
such as pneumoconiosis (particles less than 2.5 μm).
1- Total Suspended particulate:

31. It is a colorless & corrosive. It dissolves in water present
in the air to form sulfuric acid.
Sources: Volcanic eruption, fuel combustion in industry.
Hazards: Damaging to lungs (aggravation of CLD),
plants & animals.
2- Sulfur Dioxide:

32. It combines with water to form nitric acid, which is
responsible for atmospheric acidification (Acid rain).
Sources: High temperature combustion and action of
bacteria on nitrogen containing compounds in the soil.
Hazards: Acute & chronic respiratory diseases and
property destruction.
3- Nitrogen dioxides:

33. Carbon monoxide: It is highly toxic and results from
incomplete combustion. It has great affinity for
hemoglobin (Carboxy hemoglobin).
Source: Internal combustion engines.
Hazard: Combine irreversibly with hemoglobin leading to
asphyxia.
4- Carbon oxides:

34. *Carbon Dioxide: It is non-toxic in low concentration. Its
increase in concentration contributes to the problem of global
warming.
Source: Mainly respiration but it is balanced by
photosynthesis (bad effect of deforestation) and from fossil
fuel combustion.
Hazards: Increases earth temperature thus producing
undesirable climatic changes.

35. It is responsible for 2/3 of all metallic air pollution.
Sources: Leaded gasoline, lead processing, smelters,
paints and burning materials containing lead.
Hazards: Neurotoxin that causes mental retardation
especially in children.
5- Lead:

36. It is formed by a 2ry atmospheric reaction driven by solar
energy in the form of UV rays (photochemical reaction).
Source: It is formed in the atmosphere.
Hazard: Eye irritation and respiratory impairment.
6- Ozone:

37. They are volatile organic compounds that exist as gases
in the air.
Source: transportation & petroleum refineries.
Hazards: Some are carcinogens.
7- Hydrocarbons:

38. There are also minor industrial pollutants either
because they are present in minor amounts or they
have minor health hazards.
Examples: asbestos, benzene, mercury, noise,
odors, radiation etc.

39. 1. Outdoor pollution (atmospheric pollution):
The wider type of pollution.
It deals with an open & unlimited environment.
It affects more population, living things and property.
2. Indoor pollution:
It deals with limited & mostly closed environments e.g. houses &
work environments.
More hazardous than outdoor air pollution because we spent more
time inside our houses & the concentration of pollutants are much
higher (much tightly closed) than in ambient air.
Other classification of air pollution according
to its site:

41. Harmful Effects of Air PollutionHarmful Effects of Air Pollution

43. Air pollution is associated with a higher level of morbidity &
mortality. Pollutants in air can affect mostly the respiratory system,
the skin and the gastrointestinal tract.
• Exposure to air pollutants can cause or exacerbate COPD, BA,
acute respiratory diseases.
• It exacerbates cardiovascular problems and may even cause death
in individuals with impaired coronary circulation.
• Carcinogenic & mutagenic agents cause various hazards to human
health e.g. malignancy & birth defects.
1- Damage to health:

45. ∗ Eye, nose & throat irritation
∗ Bad odor & limited visibility
Due to increase of some pollutants such as
sulfur compounds, dust etc.
Sky or overhead darkening is the result of
either heavy smoke or a mixture of smoke
and fog in most urban areas.
2- Annoyance to senses:

46. Increased temperature, heavy smog cause
automobile & traffic delays, poor visibility,
lethargy, poor concentration & absenteeism from
various establishments.
3- Interference with production:

47. Metal parts of building, roofs & other metal equipment
are usually damaged chiefly by corrosion from acidic
compounds in polluted atmosphere
(SO2 forms with water vapor H2 SO4 also hydrogen
chloride reacts with water vapor to form highly
corrosive droplets of Fog).
4- Property Damage:

48. Cracking of rubber and various forms of electrical
insulation are thought to be caused by ozone (O3).
Deterioration of painted surface is caused by a variety
of air contaminants.

49. The injury to vegetation varies from invisible injury
to growth retardation of various plants, which
depend on the concentration & duration of
exposure to the toxic substance present in air as
Sulfur compounds and ozone.
5- Damage to vegetation:

51. Greenhouse gases (CO2, water vapor, trace amounts of ozone,
nitrous oxide, CFCs), act like the glass pan of a greenhouse i.e.
allowing light, IR radiation and some UV rays to pass through the
troposphere.
The earth surface absorbs much of this solar energy & degraded it
to IR radiation (heat). Some of this heat escapes into space and
some will be absorbed and trapped by the greenhouse gases and
so increase the earth's temperature.
This trapping of heat is called the greenhouse effect and leads to
global warming.
a) Global Warming:

53. Global warming

55. The ozone layer, the global sunscreen, is formed by the
interaction of O2 with light & solar energy.
Its presence in the stratosphere keeps about 99% of
harmful UV rays, thus protecting man against sunburn,
eye cataract, cancers and damage to immune system.
It prevents much of the conversion of O2 in the
troposphere to O3 which is harmful to humans.
The elevation of temperature due to the greenhouse
gases lead to the formation of O3 in the troposphere
with all its bad effects.
b) Ozone layer perforation:

58. Smog is a mixture of 1ry & 2ry pollutants that forms when
some of the 1ry pollutants interact under the influence of
sunlight.
Normally, during the day, the sun warms the air which
rises up carrying pollutants away from the surface leaving
a cooler layer with less concentration of pollutants.
Sometimes, weather conditions trap a layer of dense cool
air beneath a layer of less dense warm air, a phenomenon
called thermal inversion and thus prevents ascending of
pollutants away from earth.
c) Smog formation:

62. Due to increased emissions of SO2 & NOx from fuel
combustion, acids form from their reaction with water
leading to formation of acid rain.
This acid rain leads to damage of plants, soil, buildings
etc.
d) Acid Rain:

66. Air Quality Index (AQI)

67. The AQI is an index for reporting daily air quality.
EPA calculates the AQI for 5 major air pollutants regulated by the
Clean Air Act: ground-level O3, particle pollution (particulate
matter), CO, SO2, and NO2.
AQI scale is from 0 to 500. The higher the AQI value, the greater the
level of air pollution and the greater the health concern.
The purpose of the AQI is to help you understand what local air
quality means to your health. The AQI is divided into 6 categories
Air Quality Index (AQI)

68. AQI values are derived from air quality data readings of
pollutants affecting air quality. The index is derived using
the following formula:
Air quality index (AQI) values
AQI values below 100 are generally thought
of as satisfactory.

69. The data readings are recorded in different units of
measure, depending on the type of pollutant.

70. Air Quality Guide for Particle Pollution

72. ∗ Indoor is more hazardous due to:
1- we spent most of our time indoor 90% (house-school-
office)
2- high concentration of pollutants( much tightly closed)
than in ambient air.
Which is more hazardous outdoor or
indoor pollution?

73. ∗ Prevent health hazards
∗ Increase human comfort, production
∗ Prevent property damage
∗ Prevent vegetation damage
∗ Protect ozone layer
∗ Prevent global warming, climate changes.
Why we must control the air
pollution problem

74. 1- Outdoor:
∗ Industrial control:
A- adequate zoning of industries in special areas.
B- control at source level:
- substitution of highly toxic by less one.
- modification or changes process or equipment.
- adequate house-keeping & disposal of wastes.
C- particulate removal technique:
- filter removal of particles.
- electrostatic precipitators.
Control of air pollution

75. ∗ Transport control:
- control emission from car (lead free fuel).
- minimize traffic load inside cities (out cities
roads).
∗ Legislation:
- determine degree of pollution.
- continuous monitoring of air pollution.
- preservation of nature air purification (forest,
trees).

76. ∗ Regularly ventilate houses.
∗ Test the level of pollution.
∗ Avoid strong gasoline and solvents in houses.
∗ Grow plants in houses.
∗ Avoid smoking in houses.
∗ Don’t use aerosols spray products.
∗ Heater, stoves are properly installed and maintained.
∗ In factories; workers must used masks & regularly
checked for lung function
2- Indoor air pollution control

77. ∗ Avoid using products containing CFC
∗ Don’t use aerosol spray
∗ Check house appliances that contain ferion such as
refrigerators, freezers, air conditioners
3- Ozone layer

78. Start by yourself, how can you prevent the health
hazards of air pollution?
∗ Cultivation of plants, trees
∗ Decrease use of Freon, pesticides
∗ Sanitary waste disposal
∗ Transport control , decrease
emission of cars
Question

79. Thank you