Respiratory Health Effects
What is the concern regarding children’s respiratory health?
Air-borne pollution is of concern because of the universality of
human exposure. Both indoor and outdoor air quality contribute substantially
to the burden of illness from asthma and other respiratory problems
in children. Physicians see children with respiratory problems more
often than any other chronic health problem, and children are relatively
more likely to be hospitalized due to respiratory problems. Asthma
incidence in children under age fifteen has increased fourfold in
the last fifteen years in Canada. Despite improvements in Canadian
air quality, pollution, from local and transboundary sources, significantly
affects respiratory health among people in Ontario, the southern
Atlantic provinces and British Columbia.
What substances can affect respiratory function?
Among the major substances that are harmful to the developing respiratory
system are indoor air contaminants, such as environmental tobacco
smoke (ETS), combustion products, volatile organic compounds (VOCs),
biological compounds and allergens. A number of other pollutants
in outdoor air are present in the Canadian environment at levels
of concern, including the criteria air pollutants, such as particulates,
ground-level ozone, sulfur dioxide, oxides of nitrogen (NOx)
and various air toxics.
How are children exposed to air pollution?
Because children breathe more rapidly and inhale more air per
breath compared to adults and because they spend more time outdoors
being physically active, they tend to be more exposed to outdoor
air pollution than do adults. Children spend up to 80% of their
time indoors and are therefore also highly exposed to indoor air
contaminants. Their breathing zone is lower than adults so they
are more exposed to vehicle exhausts and heavier pollutants that
concentrate at lower levels in the air.
What are the potential health effects from air pollutants?
A variety of contaminants, in both indoor and outdoor air, are
associated with respiratory problems in children. The adverse respiratory
effects range from subtle, non-specific symptoms such as sore throat
and redness to increased cough and wheeze, increased rates of asthma
attacks, increased physician and hospital visits or admissions,
permanent reduction in lung capacity and an increased risk of Sudden
Infant Death Syndrome (SIDS).
Ozone and particulates appear to have no threshold in relation
to respiratory effects and are responsible for tangible increases
in respiratory illness. Long-erm exposure to high levels of air
pollutants is associated with significant effects on lung function
and may predispose children to developing chronic respiratory problems.
Indoor air pollutants also contribute to persistent or recurrent
respiratory symptoms, infections and allergies. Certain biological
allergens are the suspected cause of asthma, and many others will
exacerbate or trigger asthmatic episodes.
Why are children more vulnerable to effects from air pollutants?
Children are particularly vulnerable to respiratory conditions
because of their developmental stage and physical differences from
adults. Children’s lungs and airways are immature and especially
susceptible to insults from pollution. The developing lungs present
a large surface area through which pollutants may be easily absorbed.
Children breathe faster and therefore inhale and absorb a relatively
greater volume of contaminants compared to adults.
What can you do personally to prevent exposures?
One strategy for improving indoor air quality once problems are
identified is to "eliminate, separate and ventilate,"
whether this refers to ETS, chemicals, or biological compounds.
It is difficult to prevent exposure to outdoor air pollution, particularly
(but not exclusively) in urban areas. As individuals we can be aware
of air quality advisories and understand the health risks from being
exposed to poor air quality. Parents may also strive to limit children’s
strenuous activity outdoors on poor air quality days, especially
if their child has pre-existing respiratory problems.
What can we do as a society to prevent these exposures?
We have substantial evidence demonstrating the links between air
pollution and respiratory health problems in children. Respiratory
health effects are indisputably preventable. However, adequate protection
of children’s respiratory health rests upon changes at a societal
level. Indoor air quality is a virtually unregulated part of a child’s
environment. With the exception of smoking bylaws that prohibit
a child’s exposure to ETS in schools, daycares and other public
buildings, children’s protection lies with the discretion of others.
People need to be aware of the effects on indoor air quality of
the choices and activities in their daily lives.
Outdoor air quality also requires societal solutions to protect
children’s respiratory health. Lifestyle changes centred on reducing
our use of vehicles are one approach. Fundamental to a societal
response, however, are regulatory changes to improve air quality.
CAPE joins other medical groups in calling for Canadian governments
to establish more stringent standards to limit emissions from industry
and vehicles as well as more effective enforcement practices. Because
air pollution is a transboundary phenomenon, it also requires that
the Canadian government be urged to reach agreements with the United
States to reduce emissions south of the border.