Air Pollution Can Be Dangerous
For People with Heart Disease?

By: John Sawdon Director of Education & Special Projects

Air Pollution Can Be Dangerous for People with Heart Disease!

Millions of Canadians and Americans are at higher risk from air pollution because of heart or vascular disease (1). Despite progress in reducing environmental pollution during the past forty years, studies continue to show pollution-related adverse health impacts include: premature death, hospitalization for unstable angina (chest pains), heart attacks, heart failure and stroke among people with cardiovascular disease.
In responding to this both the Canadian and American governments created air quality monitoring centres throughout North America in assessing and communicating information on air quality. In Canada, Environment Canada has taken the lead for this and created The Air Quality Health Index. This AQHI is expressed as a scale and designed to communicate four things:

  • It measures the air quality in relation to your health on a scale of 1 to 10. The higher the number, the greater the health risk associated with the air quality. When the amount of air pollution is very high, the number will be reported as 10+.
  • A category that describes the level of health risk associated with the index reading (eg, Low, Moderate, High or Very High Health Risk).
  • Health messages customized to each category for both the general population and the “at risk” population.
  • Current hourly AQHI readings and maximum forecast values for today, tonight and tomorrow. (2)

The AQHI is designed to give you the above mentioned information with suggestions on how you might adjust your activity levels depending on your individual health risk from air pollution.

The scale is 1 to 10

1 2 3 4 5 6 7 8 9 10 +
  • 1-3 Low Health Risk
  • 4-6 Moderate Health Risk
  • 7-10 High Health Risk
  • 10+ Very High Health Risk

Go to the website at www.ec.gc.ca/cas-aqhi/

This website will explain and illustrate the Air Quality Health Index. It will also ask you to input your location to get a air quality health index reading for your location. The weather channel also shows the air quality health index for locations across Canada.

The United States also has an air quality health index which is called AirNow and can be reached at www.airnow.vov/?action=acquibasics.aqi This scale uses a 0 to 500 rating which is separated into six categories and colour coded for ease of understanding.

This scale is divided as follows:

When the range is Air quality is As symbolized by this colour
0-50 Good Green
51-100 Moderate Yellow
101-150 Unhealthy for Sensitive Groups Orange
151-200 Unhealthy Red
201-300 Very Unhealthy Purple
301-500 Hazardous Maroon

This website also invites you to find the air quality for your location and provides cautions depending on your health condition and the air pollution that may exist.


  1. Journal of Cardiovascular Nursing September/October 2013- Volume 28-Issue5 page 401-404 The green Heart Initiative: Using Air Quality Information to Reduce Adverse Health Effects in Patients with Heart and Vascular Disease; Cascio W. M. D., Davis Alison BA, Stone S L M.Sc.
  2. AirHealth.ca, Government of Canada Handout Be Air Aware, Air Quality Index

The articles, on the Cardiac Health Foundation of Canada website, are presented with the understanding that the Foundation is providing information only and not rendering medical advice. Please check with your family physician, specialist or health care professional before implementing any of the ideas expressed in these articles.