Canada-United States Border Air Quality Strategy: Great Lakes Basin Airshed Management Framework

In support of this pilot project under the Canada-United States Border Air Quality Strategy, Health Canada is working with Environment Canada, the United States Environmental Protection Agency and partners from other levels of government, local businesses and communities to examine the impacts of air pollution on the health of children and other vulnerable populations, such as pregnant women and diabetics, in the Great Lakes Basin region.

This geographic area has a combined population of 5.5 million people and covers 27,000 square kilometres. 50 percent of all traffic crossing the Canada-US border travels through this area.

Regional health concerns include urban pollution from diesel truck emissions, residential fuel combustion; road dust; and industrial pollution from coal-fired power plants, manufacturing, steel mills, waste incinerators, oil refineries and chemical manufacturers.

Health Canada is collaborating with Environment Canada and the University of Windsor's Centre for Environmental Health of Ontario on a range of health impact research projects as their contribution to the Great Lakes Basin Airshed Management Framework:

1. Exposure Assessment using Spatial Variability Studies
2. Personal, Indoor, and Outdoor Exposure Studies
3. Windsor Children's Respiratory Health Study
4. Air Pollution and the Effects on Pregnant Women
5. Evaluation of the Toxicity of Particulate Matter on Cultured Human Cells
6. Adverse Cardiovascular Effects of Windsor Air Pollution on Diabetic Patients
7. Time-series Studies on Mortality and Hospital Admissions in Windsor, Sarnia and London
8. Population-based Health Studies of the Great Lakes Basin Regional Airshed

Exposure Assessment using Spatial Variability Studies

Recent research findings from Europe indicate that limited monitoring within cities may underestimate human exposure to air pollution and its impact on residents' health.

The goal of this study is to determine the spatial and seasonal variability in concentrations of ambient air pollutants (respirable particulate matter, total acid vapour, and total polyaromatic hydrocarbons) at about 50 locations dispersed throughout Windsor. The study will commence in January 2005 and consists of a two-week monitoring period during each of the four seasons. Samplers will be located in the back yards of homes selected for the personal exposure study, which provides a secure location with access to power for the instruments. Sampling consists of a two week monitoring period.

Another ongoing Windsor study involves the passive spatial monitoring of nitrogen dioxide, sulphur dioxide and volatile organic compounds (VOCs) during each of the four seasons. There are approximately 60 monitors throughout Windsor and the airshed, many of which have been attached to hydro poles.

Study results will be used to fill knowledge gaps for air health risk assessment and management purposes, and to contribute to the other Border Air Quality Strategy projects.

Indoor, Outdoor, and Personal Exposure Studies

Personal exposure information is valuable in obtaining a comprehensive understanding of the risks posed to human health in specific situations.

To date, Health Canada has relied on the stationary monitors of Environment Canada's National Air Pollution Surveillance (NAPS) network to determine how exposure to air pollution impacts human health. This system has allowed Health Canada to characterize air pollution in individual Canadian cities and to observe, through the use of mortality and hospital admission data, a strong relationship between outdoor air pollution and the health of Canadians.

Recent studies conducted in the Netherlands, however, indicate that this type of monitoring underestimates both the level of exposure and the health effects themselves because these stationary monitors can only measure air pollutants in one location, rather than at the individual level. People move around indoors and outdoors while pursuing various daily activities and therefore experience different levels of exposure at different times of the day.

In order to obtain more precise estimates of human exposure to air pollution, Health Canada will undertake an important new study involving a new and more accurate form of human exposure research called personal monitoring.

Personal monitoring requires individuals to carry an array of equipment over an extended period of time (usually days) so that personal exposures to a variety of pollutants can be measured. This personal monitoring equipment, which is usually carried in a backpack, captures and displays individual-level results. This approach also provides information about the specific situations and sources of exposure experienced by healthy adults and children so that Health Canada can develop a better understanding of the risks they face.

This Windsor study has been designed to match, as closely as possible, a personal monitoring study being conducted by the US Environmental Protection Agency in Detroit so that findings may eventually be compared on both sides of the border.

In the first year, 48 adults will be monitored for five consecutive days in the summer and again in the winter. It will look at the relationships between indoor residential, outdoor residential, and personal exposures to several common air pollutants (such as ozone, sulphur dioxide, nitrogen dioxide, particulate matter, nitrate, volatile organic compounds, elemental carbon, and organic carbon). Individuals will complete time activity diaries so that their daily exposure can be attributed to different locations and time spent doing specific activities.

In the second year, some of the children involved in the respiratory health study will be monitored.

Windsor Children's Respiratory Health Study

Research has shown that children are more vulnerable to the negative effects of air pollution because:

• they breathe more rapidly;
  
• they are more active;
  
• they interact more closely with their physical environment; and
  
• they are in the critical stages of growth and development.

The purpose of this study is therefore to characterize the respiratory health of Windsor's elementary school children in relation to their levels of exposure to both indoor and outdoor air pollution.

The first phase of this study will be a large, cross-sectional, baseline questionnaire survey of all Windsor elementary students in grades one through eight to determine their respiratory health and their levels of exposure based upon assessments of specific factors related to their home and pre-existing health.

During the second phase of this study, a cross-sectional lung function inflammation test will be conducted on children in grades 4 to 6.

The third phase of the study will focus on limited groups of children selected to represent those with and without asthma, as well as those who live in higher and lower areas of air pollution. Some of these children will carry backpack instrumentation as part of a personal monitoring activity, recording their daily respiratory symptoms and lung function to more closely assess their respiratory health in response to air pollution.

Air Pollution and the Effects on Pregnant Women

Daily variations in particulate air pollution have been associated with low birth weight in several countries, including Canada. This study will take a closer look at whether or not air pollution has adverse effects on the cardiovascular and immune systems of pregnant women, and on the birth weight of those infants.

An initial Ottawa-area pilot study will investigate the feasibility of conducting a larger-scale study in Windsor, Ontario.

To conduct this study, healthy, non-smoking pregnant women living in Ottawa will be recruited through referrals from their physicians. Air pollution data will be collected from Environment Canada and the average calculated for each woman for each trimester. Blood samples will also be collected for each trimester to measure the levels of biological mediators (which are small protein molecules) that modulate body functions such as cardiovascular and immune system functions. Finally, infant birth weight will also be noted.

Evaluation of the Toxicity of Particulate Matter on Cultured Human Cells

This study will look at the toxic effects of particulate air pollutants collected from Ontario cities (including Windsor) using human cells cultured in a test tube. Researchers will examine whether or not enzyme activities change and cells die when particulate matter is added into the test tubes. This study will provide evidence on how and why particulate matter may cause adverse health effects.

Adverse Cardiovascular Effects of Windsor Air Pollution on Diabetic Patients

Studies have found that elevated levels of air pollution may increase the risk of heart attack within a few hours after exposure: this may be due to changes in blood vessel constriction. Diabetic patients, in particular, appear to be more susceptible to air pollution than the general population.

The objective of this study, therefore, is to monitor particulate air pollution on a daily basis and assess its impact over a two-and-a-half month period on the cardiovascular health of a sample group of non-smoking diabetic patients who live in Windsor. Researchers will follow these diabetic patients for 2 to 3 months to measure their blood vessel diameter (called flow-mediated vasodilation) and the concentrations of biological mediators (which are small protein molecules) in their blood that modulate body functions such as cardiovascular and immune system functions.

This study will provide information on whether or not exposure to air pollution during patients' daily activities may cause adverse health effects on diabetic patients.

Time-series Studies on Mortality and Hospital Admissions in Windsor, Sarnia and London

This study used Geographic Information Systems (GIS) to perform a time-series analysis that examined the association between daily mortality and hospital admission rates and daily changes in ozone in the southern Ontario region. This method is an improvement upon standard approaches because it increases sample size by estimating ozone concentrations in areas where there are inadequate monitoring stations. GIS methods are effective in performing ozone studies because, compared to other gases, ozone is a homogeneously distributed pollutant.

The study found that when ozone data was collected using the GIS method, there was a significant association between daily ozone concentrations and the daily number of mortality and hospital admissions.

Population-based Health Study of the Great Lakes Basin Regional Airshed

Research will be conducted to investigate community concerns about mortality and morbidity rates potentially related to long-term exposure to air pollution (such as cancer).

This study will compare air pollution levels, mortality rates for all causes of death, cancer incidence rates and morbidity rates since late 1970s across the three census divisions in which Windsor, Sarnia and London are located. Rates of these cities will then be compared with those from the province of Ontario.

Ultimately, this study will test whether or not long-term exposure to air pollution is associated with an increased number of deaths, cancer cases and morbidity in this region.