Did You Know?
Since 2001, B.C. has
invested in upgrading
over 150 monitoring units
in combination with Metro
over 85 per cent of
Did You Know?
Fine particulate matter is
known as PM2.5 because
the particles are smaller
than 2.5 microns. How
small is that? If you laid
them end to end, you
would need 20 microns
to match the thickness of
a human hair, and one
million microns to stretch
one metre. Because they
are so tiny, these particles
stay in the air longer and
travel farther than larger
particles, such as those
in dust. They can also
travel deep into our lungs
and lodge there, causing
irritation and disease.
Volatile organic compounds may occur naturally (e.g. forest fires), or result from human activities (e.g. vapours from gasoline and solvents).
Outdoor air pollution has a number of components that vary in intensity according to
their sources. They include sulphur dioxide, a gas produced from fossil fuel combustion
and natural sources such as volcanoes; volatile organic compounds1; and nitrogen oxides, produced by combustion processes such as those in engines and furnaces. Both
sulphur dioxide and nitrogen oxides can lead to acid rain. Nitrogen oxides and volatile
organic compounds can also lead to production of ground-level ozone, one of the main
ingredients in smog – and one of the worst offenders in terms of its impact on human
and environmental health.
Ground-level ozone is different from the ozone that naturally occurs high in
the atmosphere and helps to protect us from harmful ultraviolet rays. Also known
as “bad ozone,” ground-level ozone is produced when nitrogen oxides react with
volatile organic compounds.
Health effects of ground-level ozone include airway irritation and inflammation.
Repeated exposure may cause permanent lung damage. Ozone can also harm
plants, reducing crop yields and making plants more susceptible to diseases.
All of the components described above can also contribute to particulate matter (PM)
pollution. PM is air pollution in one of its most visible forms.
PM refers to airborne liquid and solid particles and occurs in two forms: primary
and secondary. Primary PM is emitted directly into the atmosphere by sources such
as wildfires, woodstoves, agricultural burning, transportation, manufacturing, and
power generation. It also includes pollen, spores and road dust. Secondary PM is
formed through chemical reactions involving the pollutants mentioned above:
nitrogen dioxide, sulphur dioxide, volatile organic compounds and ammonia.
PM is a serious health concern, as it can cause diseases such as emphysema, chronic
bronchitis, asthma and lung cancer. Because PM is composed of tiny particles invisible to
the human eye, it can be inhaled deeply into our lungs.
This Air Action Plan directly targets the sources of ground-level ozone and fine particulate
matter in three areas: transportation, industry and communities. It sets out the actions
government is taking in all these areas, and highlights everyday steps you can take to help
clear the air for all British Columbians.