What are the criteria air pollutants?

Name and discuss any of the sources, health

effect or control.
Discuss the environmental impact with example
An Air Pollutant is a substance in the air that can have adverse effects on humans and the ecosystem. The
substance can be solid particles, liquid droplets, or gasses. A pollutant can be of natural origin or manmade.
TYPES OF AIR POLLUTANTS

 Criteria air pollutants

 Non-criteria air pollutants.
Criteria Air Pollutants
Criteria Air Pollutants means an air pollutant for which acceptable levels of exposure can be determined and
for which an ambient air quality standard has been set.
Following are types criteria air pollutants:
1. Particulate matter
2. Carbon monoxide
3. Nitrogen dioxide
4. Sulphur dioxide
5. Lead (Pb)
6. Ground level ozone

Particulate Matter
PM stands for particulate matter (also called particle pollution): the term for a mixture of solid particles and
liquid droplets found in the air. Some particles, such as dust, dirt, soot, or smoke, are large or dark enough to
be seen with the naked eye. Others are so small they can only be detected using an electron microscope.
Sources of PM
These particles come in many sizes and shapes and can be made up of hundreds of different chemicals.
Some are emitted directly from a source, such as construction sites, unpaved roads, fields, smokestacks or
fires.
Most particles form in the atmosphere as a result of complex reactions of chemicals such as sulfur dioxide and
nitrogen oxides, which are pollutants emitted from power plants, industries and automobiles.
Environmental Impacts of Particulate Pollution

High levels of particulate pollution also impact the environment in addition to people’s health. Particulate
matter pollution contributes to acid rain and climate change.
The environmental impacts of particulate pollution can be devastating, with poor areas of the world hit
particularly hard by the environmental impact of PM pollution
In addition to the worsening of acid rain, particulate pollution can also change weather patterns, cause
drought, contribute to global warming, and cause the ocean to acidify.
“Particulate matter is thought to change the weather on regional scales. An example is that it suppresses
evaporation of water from the Indian Ocean leading to more lackluster Indian Monsoons, which contributes to
regional drought,” adds Wood. “Aerosols and particulate pollution are believed to increase drought around
the world by pushing tropical rainfall southward.”
Particulate pollution also contributes to the greenhouse effect, which prevents heat from leaving the planet,
leading to the melting of the polar ice caps and sea level rise. The oceans themselves acidify due to carbon
dioxide particulates, which harm sea life.
Harmful Effects of PM
Particulate matter contains microscopic solids or liquid droplets that are so small that they can be inhaled and
cause serious health problems. Some particles less than 10 micrometers in diameter can get deep into your
lungs and some may even get into your bloodstream. Of these, particles less than 2.5 micrometers in
diameter, also known as fine particles or PM2.5, pose the greatest risk to health.
Fine particles are also the main cause of reduced visibility (haze) in parts of the United States, including many
of our treasured national parks and wilderness areas.
Exposure to fine particles can cause short-term health effects such as eye, nose, throat and lung irritation,
coughing, sneezing, runny nose and shortness of breath. Exposure to fine particles can also affect lung
function and worsen medical conditions such as asthma and heart disease.
How to Reduce Particulate Matter?
We can reduce particulate matter by reducing usage of particulate matter forming appliances, avoid burning,
quit indoor smoking, walk instead of vehicle, using solar energy, regular maintaining vehicle etc.
Particulate matter is one of the most important and dangerous air pollutant presents in the air along with
harmful gases, chemicals, smoke particles, etc. Air quality is determined by studying air pollutants present in
air which is called as Air Quality Testing.
It can be affected by amount of air pollutants present in atmosphere, weather, temperature etc.
How To Reduce Particulate Matter?

 We can reduce the usage of Household products which create particulate matter
 Not to burn wood, leaves or any yard waste
 Stop smoking especially indoor
 Diesel vehicles are major source of particle pollution, it can be reduced by replacing older engines with
new engines
 Walk, cycle or use public transport or share vehicle wherever possible
 Pay attention to your maintenance of your vehicle to reduce particulate matter
 Use Indoor Air purifiers to reduce particulate matter in homes and offices
 Conserve energy by using solar energy, bio-gas, rainwater harvesting etc. to control pollution from
particulate matter
 Carbon monoxide
Carbon monoxide (CO) is an odorless, colorless gas formed by the incomplete combustion of fuels. When
people are exposed to CO gas, the CO molecules will displace the oxygen in their bodies and lead to poisoning.
Sources of CO
The greatest sources of CO to outdoor air are cars, trucks and other vehicles or machinery that burn fossil
fuels. A variety of items in your home such as unvented kerosene and gas space heaters, leaking chimneys and
furnaces, and gas stoves also release CO and can affect air quality indoors.
Environmental Effect of CO

When carbon monoxide is emitted into the atmosphere it effects the amount of greenhouse gases, which are
linked to climate change and global warming. This means that land and sea temperature increases changing to
ecosystems, increasing storm activity and causing other extreme weather events.

People and animals can be exposed to high levels of carbon monoxide during bushfires. When we are exposed
to high levels of carbon monoxide, it can make us ill and make it more difficult to have babies.

Harmful Effects of CO
Carbon monoxide is harmful because it binds to hemoglobin in the blood, reducing the ability of blood to carry
oxygen. This interferes with oxygen delivery to the body’s organs. The most common effects of CO exposure
are fatigue, headaches, confusion, and dizziness due to inadequate oxygen delivery to the brain. For people
with cardiovascular disease, short-term CO exposure can further reduce their body’s already compromised
ability to respond to the increased oxygen demands of exercise, exertion, or stress. Inadequate oxygen
delivery to the heart muscle leads to chest pain and decreased exercise tolerance. Unborn babies whose
mothers experience high levels of CO exposure during pregnancy are at risk of adverse developmental effects.
Treatment CO For Poisoning

 CPR Cardiopulmonary resuscitation is an emergency procedure consisting of chest compressions often

combined with artificial ventilation in an effort to manually preserve intact brain function until further
measures are taken to restore spontaneous blood circulation and breathing in a person who is in
cardiac arrest.
 A non-rebreather mask (NRB MASK) is a device used in medicine to assist in the delivery of oxygen
therapy.
 Hyperbaric oxygen therapy is recommended. This therapy involves breathing pure oxygen in a chamber
in which the air pressure is about two to three times higher than normal. This speeds the replacement
of carbon monoxide with oxygen in your blood.
Hyperbaric oxygen therapy may be used in cases of severe carbon monoxide poisoning. It helps protect
heart and brain tissue, which are particularly vulnerable to injury from carbon monoxide poisoning.
Hyperbaric oxygen therapy may also be recommended for pregnant women because unborn babies
are more susceptible to damage from carbon monoxide poisoning.
 Nitrogen dioxide
Nitrogen Dioxide (NO2) is one of a group of highly reactive gases known as oxides of nitrogen or nitrogen
oxides (NOx). Other nitrogen oxides include nitrous acid and nitric acid. NO2 is used as the indicator for the
larger group of nitrogen oxides.
Sources
The primary emitting sources are:

 Burning fossil fuels such as coal, oil, gas or diesel at high temperatures
 Emissions from cars trucks and buses
 Power plants, diesel-powered equipment and moveable engines
 Industrial boilers
 Unvented appliances
 Kerosene or gas space heaters, and gas stoves
 Tobacco smoke
Health effects
Breathing air with a high concentration of NO2 can irritate airways in the human respiratory system. Such
exposures over short periods can aggravate respiratory diseases, particularly asthma, leading to respiratory
symptoms (such as coughing, wheezing or difficulty breathing), hospital admissions and visits to emergency
rooms. Longer exposures to elevated concentrations of NO2 may contribute to the development of asthma
and potentially increase susceptibility to respiratory infections. People with asthma, as well as children and
the elderly are generally at greater risk for the health effects of NO2.
NO2 along with other NOx reacts with other chemicals in the air to form both particulate matter and ozone.
Both of these are also harmful when inhaled due to effects on the respiratory system.
Environmental effects

 Acid rain: Acid rain occurs when sulfur dioxide (SO2) and nitrogen oxides (NOx) are emitted into the
atmosphere and transported by wind and air currents. Acid rain has many effects, including harm to
sensitive ecosystems such as lakes and forests.
 Visibility and Haze: Nitrate particles that result from NOx contribute to the visibility and haze that
makes it difficult to see in outdoor environments.
 Nutrient pollution: Nutrient pollution is causes by excess nitrogen and phosphorus in the air and water.
Nitrogen and phosphorus support the growth of algae and aquatic plants which in turn provide
solutions for an entire ecosystem. However, when there is too much nitrogen and phosphorus, the air
and water become polluted.

Reduce Exposure to Nitrogen Dioxide

 Ensure gas appliances are properly adjusted and use exhaust fans vented to the outdoors.
 Purchase vented space heaters over unvented ones.
 Do not idle or run vehicles within the garage, especially in an attached garage. Doors from attached
garages will allow pollutants into the home.
 Live further from any power plants or locations that use sources of NO2 like diesel-powered equipment
and moveable engines.
  Avoid smoking tobacco, or at least avoid smoking tobacco indoors where it may linger afterwards.
 Utilize indoor air cleaners, such as air purifiers
 Staying indoors, especially when pollution levels are high.
 Reduce the use of motorized vehicles by walking, biking, or using other means of transportation for
close destinations. Utilize carpools with others for locations where motorized vehicles are necessary.

Sulphur dioxide
Sulfur dioxide or “SO2” is a colorless gas, reactive gas with a pungent odor. SO2 is part of a larger group of
gaseous sulfur oxides (SOx). It is of greatest concern out of the groups of SOx since it is found in higher
concentrations than other gaseous SOx, such as SO3.
SOURCES

Sulfur dioxide (SO2) is a colorless, that is produced when power plants, industrial boilers, and other facilities
burn sulfur-containing fuels such as coal and oil.
Generally, air concentrations of sulfur dioxide are highest near large industrial complexes.
The largest source of SO2 in the atmosphere is the burning of fossil fuels by power plants and other industrial
facilities. Smaller sources of SO2 emissions include: industrial processes such as extracting metal from ore;
natural sources such as volcanoes; and locomotives, ships and other vehicles and heavy equipment that burn
fuel with a high sulfur content.

Harmful Effects of SO2

Short-term
Inhalation of SO2:

 Sneezing and coughing

 Chest tightness
 Burning of the nose, throat and lungs
 Difficulty breathing
 Harm to the respiratory system
 Aggravation to diseases such as asthma and emphysema
 Short-term exposure to high levels SO2 may be life threatening
Skin/eye contact with SO2:

 Irritation of the eyes

 Frostbite
 Stinging pain, redness, and blisters
Long-term

Inhalation of SO2:

 Changes in lung function

 Decreased fertility in men and women
 Loss of smell
 Headache and dizziness
  Nausea and vomiting
 Bronchitis and shortness of breath
Skin/eye contact with SO2:

 Severe corneal damage

Environmental Effects of Sulfur Dioxide

The effects of sulfur dioxide don’t stop at human health. SO2 also plays a role in the environment that we live
in, by contributing to harmful factors on it including:

 Acid rain: SO2 and other sulfur dioxides can contribute to acid rain. Acid rain is any form of
precipitation, wet or dry, with acidic components. This rain contributes to the pollution of our air while
causing harm to the environment.
 Visibility: SO2 and other sulfur dioxides may react with other compounds forming a haze. Haze is a
basic form of air pollution that degrades visibilities in places like cities and scenic areas.
Reduce Exposure to Sulfur Dioxide?
Preventing or reducing the direct sources of SO2 may be more difficult, especially emissions from natural
sources like volcanic eruptions. Fortunately, there are other solutions to preventing or reducing your exposure
to SO2.

 Limit time spent outdoors while levels of air pollution are high. SO2 is one of many pollutants that
should be avoided. Avoiding high levels of air pollution will reduce exposure to more pollutants than
just SO2.
 Live further away from any power plants or other areas with heavy industrial processes nearby.
 Use safety equipment. Since workers typically breath in the sulfur dioxide from their work
environment, they do not bring it home with them. However, the workers can limit their exposure by
wearing masks and other required safety equipment at work.
 Utilize air cleaners, such as an air purifier, within indoor spaces to help improve the quality of your
indoor air.

Ground-level Ozone
Ozone is a gas composed of three atoms of oxygen. Ozone occurs both in the Earth's upper atmosphere and at
ground level. Ozone can be good or bad, depending on where it is found.
Called stratospheric ozone, good ozone occurs naturally in the upper atmosphere, where it forms a protective
layer that shields us from the sun's harmful ultraviolet rays. This beneficial ozone has been partially destroyed
by manmade chemicals, causing what is sometimes called a "hole in the ozone." The good news is, this hole is
diminishing.

Ozone at ground level is sourced from human activity. It is a harmful air pollutant, because of its effects on
people and the environment, and it is the main ingredient in “smog."
How is Ground-level Ozone Formed?
Ground-level ozone is created by chemical reactions of pollutants in the presence of the sun. The pollutants
involved in these chemical reactions include oxides of nitrogen (NOx) and volatile organic compounds (VOCs).
The sources of these pollutants can be emitted by cars, power plants, industrial boilers, refineries, chemical
plants, and so on.
What are the health effects of ozone?
Ozone in the air we breathe can harm our health, especially on hot sunny days when ozone can reach
unhealthy levels. People at greatest risk of harm from breathing air containing ozone include people with
asthma.
What are the environmental effects of ozone?
Elevated exposures to ozone can affect sensitive vegetation and ecosystems, including forests, parks, wildlife
refuges and wilderness areas. In particular, ozone can harm sensitive vegetation during the growing season.
Control

The Clean Air Act requires EPA to set national ambient air quality standards (NAAQS) for ozone and five other
pollutants considered harmful to public health and the environment (the other pollutants are particulate
matter, nitrogen oxides, carbon monoxide, sulfur dioxide and lead). The law also requires EPA to periodically
review the standards to ensure that they provide adequate health and environmental protection, and to
update those standards as necessary.

Lead (Pb)
Lead is a soft and highly toxic elemental metal found naturally in the environment as well as in manufactured
products. Exposure to lead can occur in several ways like inhalation of air or ingestion of lead in food, water,
soil can cause ailment. It is usually extracted from ore deposits along with copper, silver, and zinc. Australia,
the United States, and China are the world's leading producers of lead.

SOURCES
Sources of lead emissions vary from one area to another. At the national level, major sources of lead in the air
are ore and metals processing and piston-engine aircraft operating on leaded aviation fuel. Other sources are
waste incinerators, utilities, and lead-acid battery manufacturers. The highest air concentrations of lead are
usually found near lead smelters.

Although lead is naturally occurring, most of it in the environment today got there from a range of earlier
commercial and industrial uses by people. It has been widely used in cables, pipes, paints, and pesticides.

Effects of lead on human health

Once taken into the body, lead distributes throughout the body in the blood and is accumulated in the
bones. Depending on the level of exposure, lead can adversely affect the nervous system, kidney function,
immune system, reproductive and developmental systems and the cardiovascular system. Lead exposure also
affects the oxygen carrying capacity of the blood. The lead effects most likely to be encountered in current
populations are neurological effects in children. Infants and young children are especially sensitive to lead
exposures, which may contribute to behavioral problems, learning deficits and lowered IQ.
 Effects of lead on ecosystems
Lead is persistent in the environment and can be added to soils and sediments through deposition from
sources of lead air pollution. Other sources of lead to ecosystems include direct discharge of waste streams to
water bodies and mining. Elevated lead in the environment can result in decreased growth and
reproduction in plants and animals, and neurological effects in vertebrates.