Nothing could be more fundamental to your health than the quality of the air you breathe. In Canada, air pollution and aeroallergens have significant implications for health. Health impacts include lung disease, heart disease and lung cancer.
It is now well-established by researchers that climate change could result in a deterioration of several aspects of air quality, including:
Who is at risk?
Air quality is most likely to cause health problems in vulnerable groups, such as:
Ground-level ozone, a major component of smog, is created when gases in the environment react in the presence of heat and sunlight.
Researchers predict that, because ground-level ozone and weather are so closely linked, climate change will cause higher average ozone concentrations, more frequent peak ozone periods and longer summers which can increase summer ozone periods.Health effects
Short-term exposure to ground-level ozone, over hours, days or weeks, can result in:
Long-term exposure to ground-level ozone, over years or decades, can cause death from breathing problems.
Particulate matter is a mixture of tiny particles of different sizes which enter the air from a variety of natural and man-made sources, including dust, fires, vehicles and industry. The impact of climate change on particulate matter is less well understood than ozone. It is known that rain can reduce particulate matter from the air. As precipitation patterns are harder to predict there is uncertainty on how climate change will impact particulate matter in Canada and therefore more research is needed. However, research has shown that climate change could increase frequency and intensity of forest fires, which would result in an increase in particulate matter.
Short-term exposure to particulate matter can result in:
Long-term exposure to particulate matter can result in:
Extreme heat can impact health by causing, for example, heat stroke, but when heat is combined with air pollution, the negative health effects are compounded:
Aeroallergens are pollen and spores in the air that cause allergic responses.
Research suggests that climate change will increase allergens in the air and related allergic diseases as warmer weather and milder winters can result in increased pollen production in plants. More frequent thunderstorms may also put more pollen into the air. Furthermore, higher carbon dioxide levels, due to climate change, can increase plant growth and pollen production.
A longer pollen season could mean:
For example, in Canada, the ragweed pollen season is now about one month longer because of warming temperatures.
Aeroallergens cause allergic responses—most often allergic rhinitis (e.g. hay fever), asthma and eczema. Exposure to higher concentrations of aeroallergens may cause more severe allergies. In Canada nearly 50% of children suffer from hay fever and over 20% have been diagnosed with asthma.
As people spend approximately 90% of their time indoors, the quality of the indoor environment is an important consideration for health. Indoor environments can be contaminated by chemical and organic pollutants that migrate from outdoors or that result from gas stoves and other indoor sources, such as building materials, pets, radon, and environmental tobacco smoke.
With climate change, any changes in the outdoor levels of pollutants or allergens could affect indoor levels. Extreme weather conditions associated with climate change may lead to risks of infiltration of water into indoor spaces (flooding) and associated growth of mold or bacteria.
Flooding may cause building materials to breakdown and lead to off-gassing of chemicals.
In addition, any measures implemented in buildings or homes to reduce energy use in buildings, such as lowering ventilation rates may cause higher exposures to pollutants emitted from indoor sources.
There is a need to be aware of the potential health risks related to climate change and the indoor environment, especially for vulnerable populations such as children, elderly and those with compromised immune systems.
For more information about how to reduce levels of indoor contaminants please visit the Health Canada Indoor Air Quality website.
You can lower your exposure to air pollution when you:
You can monitor outdoor air quality