Air pollution and general practitioner access and utilization: a population based study in Sarnia, 'Chemical Valley,' Ontario.

BACKGROUND: Health impacts of poor environmental quality have been identified in studies around the world and in Canada. While many of the studies have identified associations between air pollution and mortality or morbidity, few have focused on the role of health care as a potential moderator of impacts. This study assessed the determinants of health care access and utilization in the context of ambient air pollution in Sarnia, Ontario, Canada. METHODS: Residents of Sarnia participated in a Community Health Study administered by phone, while several ambient air pollutants including nitrogen dioxide (NO2), sulphur dioxide (SO2) and the volatile organic compounds benzene, toluene, ethylbenzene, mp- and o-xylene (BTEX) were monitored across the city. Land Use Regression models were used to estimate individual exposures to the measured pollutants and logistic regression models were utilized to assess the relative influence of environmental, socioeconomic and health related covariates on general practitioner access and utilization outcomes. RESULTS: The results show that general practitioner use increased with levels of exposure to nitrogen dioxide (NO2- Odds Ratio [OR]: 1.16, p < 0.05) and sulphur dioxide (SO2- OR: 1.61, p < 0.05). Low household income was a stronger predictor of having no family doctor in areas exposed to high concentrations of NO2 and SO2. Respondents without regular care living in high pollution areas were also more likely to report travelling or waiting for care in excess of 20 minutes (OR: 3.28, p < 0.05) than their low exposure counterparts (OR: 1.11, p > 0.05). CONCLUSIONS: This study provides evidence for inequitable health care access and utilization in Sarnia, with particular relevance to its situation as a sentinel high exposure environment. Levels of exposure to pollution appears to influence utilization of health care services, but poor access to primary health care services additionally burden certain groups in Sarnia, Ontario, Canada.

What motivates farmers to participate in the Nova Scotia environmental farm plan program? Evidence and environmental policy implications.

Program stakeholders are interested in better understanding farmers' experience, and factors that affect farmer participation in the relatively new Environmental Farm Plan (EFP) program, implemented in several provinces in Canada. To increase relevance of the research findings to EFP program administrators and policy makers, the research methods emphasised determining whether relationships exist among program-related variables, and how such relationships affect farmers' decision choices and behaviour. Traditional farmer and farm attributes that have contrasting effects in agricultural innovation adoption and conservation management (namely age, and formal education completed), were not associated with EFP program participation. Farm income, years of farming experience, and type of agribusiness managed were associated with participation in the Nova Scotia EFP program. Although program participants tended to have higher incomes, overall, non-financial considerations dominated monetary considerations in Nova Scotia farmers' reasons for participating in the Nova Scotia EFP. Helping to publicize positive farm stewardship practices was reported as the most important reason for participating in the EFP scheme, followed by its use to help improve relationships with non-farming neighbours, and to comply with government environmental regulations. In contrast, and somewhat a surprising finding, minimizing potential farm environmental risk, program administrators' raison d'être for promoting the NS EFP, was ranked the lowest, with no respondent rating that as a "very important" or "extremely important" reason for participating in the EFP program.

Spatial variability of ambient nitrogen dioxide and sulfur dioxide in Sarnia, "Chemical Valley," Ontario, Canada.

This study aimed at developing models to predict nitrogen dioxide (NO(2)) and sulfur dioxide (SO(2)) concentrations in Sarnia, "Chemical Valley", Ontario, Canada, and model the intra-urban variation of ambient NO(2) and SO(2) in the city for a community health study. NO(2) and SO(2) samples were monitored with Ogawa passive samplers at 39 locations across the city for 2 wk during the fall of 2005. The final land use regression models were constructed to generate independent variables that might best predict NO(2) and SO(2) concentrations. The coefficients of determinations for the final NO(2) and SO(2) models were .79 and .66, respectively. The explanatory variables in the final NO(2) model were: proximity to the industrial core, industrial areas within 1600 m, highways within 400 m, and dwelling counts within 2400 m. The variables in the final SO(2) model were: proximity to the industrial core, industrial areas within 1200 m, and major roads within 100 m. The spatial variations captured in these analyses are being used to estimate ambient pollution concentrations for a large health study.