Particulate matter and manganese exposures in Toronto, Canada

摘要: Abstract Methylcyclopentadienyl manganese tricarbonyl (MMT) is a manganese-based gasoline additive used to enhance automobile performance. MMT has been in Canadian for about 20 yr. Because of the potential increased levels Mn particulate matter resulting from automotive exhausts, large-scale population-based exposure study (∼1000 participant periods) was conducted Toronto, Canada, estimate distribution 3-day average personal exposures (PM2.5 and PM10) Mn. A stratified, three-stage, two-phase probability, longitudinal sample design metropolitan population employed. Residential indoor outdoor, ambient (at fixed site on roof) PM2.5, PM10, were also measured. Supplementary data traffic counts, meteorology, gasoline, occupations, activities (e.g. amount vehicular usage) collected. Overall precision (%RSD) analysis duplicate co-located samples ranged 2.5 5.0% 3.1 5.5% The detection limits 1.47 3.45 μg m-3 PM10 PM2.5 fractions, respectively, 5.50 1.83 ng m-3 respectively. These low permitted reporting concentrations >98% samples. For (median 48.5 μg m-3) much higher than either (23.1 μg m-3) or outdoor (23.6 μg m-3). median personal, indoor, 28.4, 15.4 13.2 μg m-3, correlation between high (0.79), while correlations roof (0.16–0.27). Indoor concentration distributions (in PM10), unlike matter, exhibited lower less variable that corresponding data. 8.0 ng m-3, compared with 4.7 8.6 ng m-3, distributions. highest occurred vs (0.56) (0.66), (0.56). expressed ppm (w/w), revealed highest, followed by site, personal. showed statistically significant (0.68) all other fixed-site quite small. suggest different sources microenvironments produce particle dissimilar composition. results indicate neither roof- nor can adequately predict exposures.