PHLT612: Special Issues in Public Health – II
Unit 01: - Air and Noise Pollution Control: Definition of Air Pollution: Pollution and
Their Sources – Effects on Human Health, Vegetation and Climate of Air Pollution –
Air Pollution Control Legislation – Noise Pollution: Sources and Effects – Control
Measures.
Air pollution
Air pollution is the contamination of air due to the presence of substances in the atmosphere that are harmful
to the health of humans and other living beings, or cause damage to the climate or to materials. There are
many different types of air pollutants, such as gases (including ammonia, carbon monoxide, sulfur dioxide,
nitrous oxides, methane, carbon dioxide and chlorofluorocarbons), particulates (both organic and inorganic),
and biological molecules. Air pollution can cause diseases, allergies, and even death to humans; it can also
cause harm to other living organisms such as animals and food crops, and may damage the natural
environment (for example, climate change, ozone depletion or habitat degradation) or built environment (for
example, acid rain). Both human activity and natural processes can generate air pollution.
Air pollution is a significant risk factor for a number of pollution-related diseases, including respiratory
infections, heart disease, COPD, stroke and lung cancer. Growing evidence suggests that air pollution
exposure may be associated with reduced IQ scores, impaired cognition, increased risk for psychiatric
disorders such as depression and detrimental perinatal health. The human health effects of poor air quality
are far reaching, but principally affect the body's respiratory system and the cardiovascular system.
Individual reactions to air pollutants depend on the type of pollutant a person is exposed to, the degree of
exposure, and the individual's health status and genetics. Outdoor air pollution alone causes 2.1 to 4.21
million deaths annually, making it one of the top contributors to human death. Overall, air pollution causes
the deaths of around 7 million people worldwide each year, or a global mean loss of life expectancy (LLE)
of 2.9 years, and is the world's largest single environmental health risk. Indoor air pollution and poor urban
air quality are listed as two of the world's worst toxic pollution problems in the 2008 Blacksmith Institute
World's Worst Polluted Places report. The scope of the air pollution crisis is enormous: 90% of the world's
population breathes dirty air to some degree. Although the health consequences are extensive, the way the
problem is handled is often haphazard
, Sources of air pollution
A. Anthropogenic (human-made) sources
These are mostly related to the burning of fuel.
• Stationary sources include:
o smoke stacks of fossil fuels and biomass power stations (
o burning of traditional biomass such as wood, crop waste and dung. (In developing and poor
countries, traditional biomass burning is the major source of air pollutants.
o manufacturing facilities (factories)
▪ a 2014 study found that in China equipment-, machinery-, and devices-manufacturing
and construction sectors contributed more than 50% of air pollutant emissions
o waste incineration (incinerators as well as open and uncontrolled fires of mismanaged waste,
making up about a fourth of municipal solid terrestrial waste)
o furnaces and other types of fuel-burning heating devices
• Mobile sources include motor vehicles, trains (particularly diesel locomotives), marine vessels and
aircraft.
• Controlled burn practices in agriculture and forest management. Controlled or prescribed burning is a
technique sometimes used in forest management, farming, prairie restoration or greenhouse gas
abatement. Fire is a natural part of both forest and grassland ecology and controlled fire can be a tool
for foresters. Controlled burning stimulates the germination of some desirable forest trees, thus
renewing the forest.
B. Natural sources
• Dust from natural sources, usually large areas of land with little vegetation or no vegetation
• Methane, emitted by the digestion of food by animals, for example cattle
• Radon gas from radioactive decay within the Earth's crust. Radon is a colorless, odorless, naturally
occurring, radioactive noble gas that is formed from the decay of radium. It is considered to be a
health hazard. Radon gas from natural sources can accumulate in buildings, especially in confined
areas such as the basement and it is the second most frequent cause of lung cancer, after cigarette
smoking.
• Smoke and carbon monoxide from wildfires. During periods of active wildfires, smoke from
uncontrolled biomass combustion can make up almost 75% of all air pollution by concentration.
• Vegetation, in some regions, emits environmentally significant amounts of volatile organic
compounds (VOCs) on warmer days. These VOCs react with primary anthropogenic pollutants –
specifically, NOx, SO2, and anthropogenic organic carbon compounds – to produce a seasonal haze
of secondary pollutants. Black gum, poplar, oak and willow are some examples of vegetation that
can produce abundant VOCs. The VOC production from these species result in ozone levels up to
eight times higher than the low-impact tree species.
• Volcanic activity, which produces sulfur, chlorine, and ash particulates
C. Emission factors
Air pollutant emission factors are reported representative values that attempt to relate the quantity of a
pollutant released to the ambient air with an activity associated with the release of that pollutant. These
factors are usually expressed as the weight of pollutant divided by a unit weight, volume, distance, or
duration of the activity emitting the pollutant (e.g., kilograms of particulate emitted per tonne of coal
burned). Such factors facilitate estimation of emissions from various sources of air pollution. In most cases,
these factors are simply averages of all available data of acceptable quality, and are generally assumed to be
representative of long-term averages.
Unit 01: - Air and Noise Pollution Control: Definition of Air Pollution: Pollution and
Their Sources – Effects on Human Health, Vegetation and Climate of Air Pollution –
Air Pollution Control Legislation – Noise Pollution: Sources and Effects – Control
Measures.
Air pollution
Air pollution is the contamination of air due to the presence of substances in the atmosphere that are harmful
to the health of humans and other living beings, or cause damage to the climate or to materials. There are
many different types of air pollutants, such as gases (including ammonia, carbon monoxide, sulfur dioxide,
nitrous oxides, methane, carbon dioxide and chlorofluorocarbons), particulates (both organic and inorganic),
and biological molecules. Air pollution can cause diseases, allergies, and even death to humans; it can also
cause harm to other living organisms such as animals and food crops, and may damage the natural
environment (for example, climate change, ozone depletion or habitat degradation) or built environment (for
example, acid rain). Both human activity and natural processes can generate air pollution.
Air pollution is a significant risk factor for a number of pollution-related diseases, including respiratory
infections, heart disease, COPD, stroke and lung cancer. Growing evidence suggests that air pollution
exposure may be associated with reduced IQ scores, impaired cognition, increased risk for psychiatric
disorders such as depression and detrimental perinatal health. The human health effects of poor air quality
are far reaching, but principally affect the body's respiratory system and the cardiovascular system.
Individual reactions to air pollutants depend on the type of pollutant a person is exposed to, the degree of
exposure, and the individual's health status and genetics. Outdoor air pollution alone causes 2.1 to 4.21
million deaths annually, making it one of the top contributors to human death. Overall, air pollution causes
the deaths of around 7 million people worldwide each year, or a global mean loss of life expectancy (LLE)
of 2.9 years, and is the world's largest single environmental health risk. Indoor air pollution and poor urban
air quality are listed as two of the world's worst toxic pollution problems in the 2008 Blacksmith Institute
World's Worst Polluted Places report. The scope of the air pollution crisis is enormous: 90% of the world's
population breathes dirty air to some degree. Although the health consequences are extensive, the way the
problem is handled is often haphazard
, Sources of air pollution
A. Anthropogenic (human-made) sources
These are mostly related to the burning of fuel.
• Stationary sources include:
o smoke stacks of fossil fuels and biomass power stations (
o burning of traditional biomass such as wood, crop waste and dung. (In developing and poor
countries, traditional biomass burning is the major source of air pollutants.
o manufacturing facilities (factories)
▪ a 2014 study found that in China equipment-, machinery-, and devices-manufacturing
and construction sectors contributed more than 50% of air pollutant emissions
o waste incineration (incinerators as well as open and uncontrolled fires of mismanaged waste,
making up about a fourth of municipal solid terrestrial waste)
o furnaces and other types of fuel-burning heating devices
• Mobile sources include motor vehicles, trains (particularly diesel locomotives), marine vessels and
aircraft.
• Controlled burn practices in agriculture and forest management. Controlled or prescribed burning is a
technique sometimes used in forest management, farming, prairie restoration or greenhouse gas
abatement. Fire is a natural part of both forest and grassland ecology and controlled fire can be a tool
for foresters. Controlled burning stimulates the germination of some desirable forest trees, thus
renewing the forest.
B. Natural sources
• Dust from natural sources, usually large areas of land with little vegetation or no vegetation
• Methane, emitted by the digestion of food by animals, for example cattle
• Radon gas from radioactive decay within the Earth's crust. Radon is a colorless, odorless, naturally
occurring, radioactive noble gas that is formed from the decay of radium. It is considered to be a
health hazard. Radon gas from natural sources can accumulate in buildings, especially in confined
areas such as the basement and it is the second most frequent cause of lung cancer, after cigarette
smoking.
• Smoke and carbon monoxide from wildfires. During periods of active wildfires, smoke from
uncontrolled biomass combustion can make up almost 75% of all air pollution by concentration.
• Vegetation, in some regions, emits environmentally significant amounts of volatile organic
compounds (VOCs) on warmer days. These VOCs react with primary anthropogenic pollutants –
specifically, NOx, SO2, and anthropogenic organic carbon compounds – to produce a seasonal haze
of secondary pollutants. Black gum, poplar, oak and willow are some examples of vegetation that
can produce abundant VOCs. The VOC production from these species result in ozone levels up to
eight times higher than the low-impact tree species.
• Volcanic activity, which produces sulfur, chlorine, and ash particulates
C. Emission factors
Air pollutant emission factors are reported representative values that attempt to relate the quantity of a
pollutant released to the ambient air with an activity associated with the release of that pollutant. These
factors are usually expressed as the weight of pollutant divided by a unit weight, volume, distance, or
duration of the activity emitting the pollutant (e.g., kilograms of particulate emitted per tonne of coal
burned). Such factors facilitate estimation of emissions from various sources of air pollution. In most cases,
these factors are simply averages of all available data of acceptable quality, and are generally assumed to be
representative of long-term averages.
