Assessing the Long-Term Health Effects of Childhood Exposure to Adverse Air Quality: Case Study from Hamilton, Ontario (1975 - 2005)

Abstract

This thesis examines the relationship between childhood exposure to air pollution and long-term health. The research is based on an earlier study (1978-1986) that examined the relationship between exposure to air quality and respiratory health for a cohort of elementary school-aged children (n=3,202). These children resided in four distinct neighbourhoods in Hamilton, Ontario, which exhibited significant gradients in air pollution levels. Informed by the Life Course Health Development model, a survey was developed and administered on a reconstructed cohort (n = 395). The following objectives were addressed: 1) to determine the current health status of the reconstructed cohort; 2) to assess the potential relationship between childhood exposure to air pollution and adult respiratory health; and, 3) to explore factors mediating this relationship. Data was collected for a range of variables including residential and occupational histories, socio-demographic variables, and health outcomes. The dataset was merged with data from childhood on respiratory health, exposure to air pollution, and socio-demographic variables. Results indicate that a relatively high percentage of respondents had asthma in childhood (11%) compared to the original cohort (5.5%). In addition, prevalence rates of most health outcomes were higher than those of the Canadian population. Despite the gradient in air pollution levels, there were no significant differences in health status across neighborhoods. However, results of bi-variate and multi-variate analysis indicate possible significant associations between childhood exposure to S02 and hospital visits for asthma, asthma incidence in adulthood, and ever being diagnosed with asthma for females. For males, results suggest that childhood exposure to S02 is not linked to respiratory health. Factors related to the macro and micro environments also play significant roles in long-term health. This thesis made significant contributions to knowledge by suggesting that childhood exposure to S02 may impact long-term respiratory health for females, and may be linked to inflammatory diseases.