Air Pollution and Children

According to the World Health Organization (WHO) urban air quality in 56% of cities, with populations greater than 100,000, in high-income countries do not meet the WHO air quality guidelines. That percentage increases to 98% in low- and middle-income countries. With decreased air quality comes increased risk of respiratory diseases. Three million deaths a year are connected to outdoor air pollution, but indoor air pollution can be just as bad (WHO 2016).

In industrialized countries asthma is the most common childhood illness after the common cold. For children, it is the leading cause of chronic disease, the leading cause of hospitalization, and the leading cause of school absenteeism.

In Canada, 10% to 15% of our children are reported to have asthma, but the BC Lung Association believes the rate could be as high as 20% - a travesty of our time.

In the United States an estimated 6.1 million children under eighteen years of age have asthma. Asthma prevalence in children 1-17 years of age from 2001-2010 increased at a rate of 1.4% per year (CDC).

What is the cause of these epidemic-like increases?

It has been known for a long time that air pollution aggravates asthma but now studies are suggesting that it may also be one of its causes. Scientists are beginning to tackle the cumulative impacts on children of repeated exposures to air pollution. They are now seeing that air pollution effects both asthmatic and non-asthmatic children causing a continuum of injuries ranging from reduction in the ability to breath normally to death.

Spirometry can be used to detect some of these early injuries. Basically, this involves having a patient breath as hard and fast as possible through a tube while measuring the results. Swabbing or rinsing nasal passages is another way of detecting damage. Certain metabolites in the rinse are indicators of inflammation which, in turn, indicates that the body is fighting injury.

"Eventually, the repeated shocks to the children's maturing bodies takes a toll. One of the earliest effects is to slow the growth of respiratory systems, with permanent, perhaps irrevocable consequences. Children breathe more pound-for-pound than adults, spend more time outdoors and, perhaps most importantly, their respiratory, hormone and other systems are still growing and maturing and thus vulnerable to injury."
(Taken from Health and Clean Air Newsletter, Spring 2003 Issue, co-edited by Curtis Moore and Dr. David Bates).

In developing countries, indoor cooking and heating fuel can range from twigs to dried dung resulting in devastatingly high fine particulate pollution. Every year in these countries 4.1 million children under the age of 5 die from acute respiratory illness. One quarter of these deaths are directly related to indoor smoke exposure.

In our country 'soot' exposure in many areas comes primarily from cars, trucks buses, factories and generators burning fuels such as coal. Some areas experience high exposure through the burning of forest and agricultural residues. Many communities, like ours, suffer from exposure to winter wood smoke.

There are many ways we can reduce air pollution and our exposure to it. A good start is simply becoming aware of it and connecting the dots, not just to the staggering asthma statistics, but to the incredible suffering wreaked upon so many of our children. Awareness breeds personal and political commitment. Nothing short of that will bring any significant change.


Air pollution exacerbates existing asthma. There is growing evidence that specific pollutants, like those related to traffic, initiate asthma.

Is the #1 reason for infant hospitalization.
Woodsmoke causes an 8% increase in bronchiolitis
(Karr et al. AJRCCM 2009)

Otitis Media (Ear Infection)
Is the #1 reason for children under 2 years old to see a physician.
Is the #1 reason for children under 5 years old to receive antibiotics
10% of otitis media is directly linked to woodsmoke pollution.
(E. MacIntyre, PhD Thesis, UBC, 2010)
Woodsmoke exposures cause a 32% increase in middle ear infections.

Low Birth Weight and Pre-Term Birth
Living 50 meters or closer to a provincial highway increases low birth with by 21%.
(Brauer er al. EHP 2008; Clark er al. EHP 2010. Karr et al. AM J Resp Crit Care Med 2009; MacIntyre et al. Epidemiology 2011).

Reduced Lung Function Growth
(Gauderman et al. MEJM 2004)
Severe air pollution can actually stunt lung development in children. It can also interfere with lung function development leading to earlier than normal disability and death.