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Background Exposure to indoor air particles pollution increases the incidence and mortality of respiratory and cardiovascular diseases, especially in the elderly population. Objective To explore the effect of indoor air particles on cardiopulmonary-related physiological indexes of the elderly and short-term use of air purifiers on the improvement of cardiopulmonary health of the elderly. Methods A randomized, double-blind, crossover trial was conducted in January 2020 on 24 healthy older adults selected from a senior apartment in Jiangbei District of Chongqing. These included older adults equally divided into two groups alternately using real and sham air purifiers for 48 h with a 12-days washout interval by complete randomization. 14 health indexes including biomarkers of circulatory system inflammation, coagulation, oxidative stress and pulmonary function, blood pressure, heart rate, exhaled fractional nitric oxide (FeNO) were measured. Linear mixed-effect model was used to evaluate the effect of the air purifiers on health indexes. Results The results of the linear mixed-effect model showed that compared with the sham purifiers, fibrinogen, MCP-1 and MPO in the blood inflammatory indicators were changed by -15.1%〔95%CI (-23.1%, -6.3%) , P

Cooking is the main source of ultrafine particles (UFP) in homes. This study investigated the effect of venting range hood flow rate on size-resolved UFP concentrations from gas stove cooking. The same cooking protocol was conducted 60 times using three venting range hoods operated at six flow rates in twin research houses. Size-resolved particle (10–420 nm) concentrations were monitored using a NanoScan scanning mobility particle sizer (SMPS) from 15 min before cooking to 3 h after the cooking had stopped. Cooking increased the background total UFP number concentrations to 1.3 × 103 particles/cm3 on average, with a mean exposure-relevant source strength of 1.8 × 1012 particles/min. Total particle peak reductions ranged from 25% at the lowest fan flow rate of 36 L/s to 98% at the highest rate of 146 L/s. During the operation of a venting range hood, particle removal by deposition was less significant compared to the increasing air exchange rate driven by exhaust ventilation. Exposure to total particles due to cooking varied from 0.9 to 5.8 × 104 particles/cm3·h, 3 h after cooking ended. Compared to the 36 L/s range hood, higher flow rates of 120 and 146 L/s reduced the first-hour post-cooking exposure by 76% and 85%, respectively. © 2018 Crown Copyright. Published with license by Taylor & Francis Group, LLC.

Cooking is one of the main sources of indoor air pollutants, and may even exceed the contribution from outdoor sources. This pilot study examines the use of different flow-rate fans during cooking and tests whether continuing to run the fan after cooking significantly improves pollutant removal rates and integrated exposures. Tests were carried out in the Canadian Centre for Housing Technology's twin research houses, in Ottawa, Ontario. We completed the same cooking protocol 60 times on a gas stove, testing 6 different flow rates on three different over-the-range exhaust fans, while continuously measuring UFP, PM2.5, NO2, and NO. The fan was operated during cooking for all tests and then either turned off or left on after cooking for the duration of the three hour test. We estimated decay rates, source emission rates, and integrated exposures to measured pollutants following the cooking test. The results showed that while leaving the fan on after cooking generally increased decay rates, it had a relatively small effect on integrated exposures compared to the effects of fan flow rate and the specific fan used during cooking. For PM2.5, the effect of running an exhaust fan for 15 min after cooking was similar in magnitude to the impact of a 100 cfm increase in the flow rate used while cooking: both were associated with a decrease in 15-min integrated exposure of roughly 3 μg m−3. This suggests that one can partially compensate for a low flow rate exhaust fan by continuing to run the fan after cooking.

Background: We do not currently understand how spatiotemporal variations in the composition of fine particulate air pollution [fine particulate matter with aerodynamic diameter [less than or equal to] 2.5 [micro]m ([PM.sub.2.5])] affects population health risks. However, recent evidence suggests that joint concentrations of transition metals and sulfate may influence the oxidative potential (OP) of [PM.sub.2.5] and associated health impacts. Objectives: The purpose of the study was to evaluate how combinations of transition metals/OP and sulfur content in outdoor [PM.sub.2.5] influence associations with acute cardiovascular events. Methods: We conducted a national case-crossover study of outdoor [PM.sub.2.5] and acute cardiovascular events in Canada between 2016 and 2017 (93,344 adult cases). Monthly mean transition metal and sulfur (S) concentrations in [PM.sub.2.5] were determined prospectively along with estimates of OP using acellular assays for glutathione ([OP.sup.GSH]), ascorbate ([OP.sup.AA]), and dithiothreitol depletion ([OP.sup.DTT]). Conditional logistic regression models were used to estimate odds ratios (OR) [95% confidence intervals (CI)] for [PM.sub.2.5] across strata of transition metals/OP and sulfur. Results: Among men, the magnitudes of observed associations were strongest when both transition metal and sulfur content were elevated. For example, an OR of 1.078 (95% CI: 1.049, 1.108) (per 10 [micro]g/[m.sup.3]) was observed for cardiovascular events in men when both copper and S were above the median, whereas a weaker association was observed when both elements were below median values (OR= 1.019, 95% CI: 1.007, 1.031). A similar pattern was observed for OP metrics. [PM.sub.2.5] was not associated with acute cardiovascular events in women. Discussion: The combined transition metal and sulfur content of outdoor [PM.sub.2.5] influences the strength of association with acute cardiovascular events in men. Regions with elevated concentrations of both sulfur and transition metals in [PM.sub.2.5] should be examined as priority areas for regulatory interventions. https://doi.org/10.1289/EHP9449, Introduction Numerous epidemiological studies have documented the acute cardio-respiratory health impacts of outdoor fine particulate air pollution [fine particulate matter with aerodynamic diameter [less than or equal to] 2.5 [micro]m [...]

Background: Populations are simultaneously exposed to outdoor concentrations of oxidant gases (i.e., O 3 and NO 2 ) and fine particulate air pollution (PM 2.5 ). Since oxidative stress is thought to be an important mechanism explaining air pollution health effects, the adverse health impacts of oxidant gases may be greater in locations where PM 2.5 is more capable of causing oxidative stress.Methods: We conducted a cohort study of 2 million adults in Canada between 2001 and 2016 living within 10 km of ground-level monitoring sites for outdoor PM 2.5 components and oxidative potential. O x exposures (i.e., the redox-weighted average of O 3 and NO 2 ) were estimated using a combination of chemical transport models, land use regression models, and ground-level data. Cox proportional hazards models were used to estimate associations between 3-year moving average O x and mortality outcomes across strata of transition metals and sulfur in PM 2.5 and three measures of PM 2.5 oxidative potential adjusting for possible confounding factors.Results: Associations between O x and mortality were consistently stronger in regions with elevated PM 2.5 transition metal/sulfur content and oxidative potential. For example, each interquartile increase (6.27 ppb) in O x was associated with a 14.9% (95% CI = 13.0, 16.9) increased risk of nonaccidental mortality in locations with glutathione-related oxidative potential (OP GSH ) above the median whereas a 2.50% (95% CI = 0.600, 4.40) increase was observed in regions with OP GSH levels below the median (interaction P value <0.001).Conclusion: Spatial variations in PM 2.5 composition and oxidative potential may contribute to heterogeneity in the observed health impacts of long-term exposures to oxidant gases. [ABSTRACT FROM AUTHOR]

ABSTRACT The Windsor, Ontario Exposure Assessment Study evaluated the contribution of ambient air pollutants to personal and indoor exposures of adults and asthmatic children living in Windsor, Ontario, Canada. In [...]