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BACKGROUND: Coarse particulate matter (PM10-2.5) is primarily mechanically generated and includes crustal material, brake and tire wear, and biological particles. PM10-2.5 is associated with pulmonary disease, which can lead to right ventricular (RV) dysfunction. Although RV characteristics have been associated with combustion-related pollutants, relationships with PM10-2.5 remain unknown. OBJECTIVES: To quantify cross-sectional associations between RV dysfunction and PM10-2.5 mass and components among older adults and susceptible populations. METHODS: We used baseline cardiac magnetic resonance images from 1,490 participants (45-84 y old) from the Multi-Ethnic Study of Atherosclerosis and assigned 5-y residential concentrations of PM10-2.5 mass, copper, zinc, phosphorus, silicon, and endotoxin, using land-use regression models. We quantified associations with RV mass, end-diastolic volume, and ejection fraction after control for risk factors and copollutants using linear regression. We further examined personal susceptibility. RESULTS: We found positive associations of RV mass and, to a lesser extent, end diastolic volume with PM10-2.5 mass among susceptible populations including smokers and persons with emphysema. After adjustment for copollutants, an interquartile range increase in PM10-2.5 mass (2:2 μg/m³) was associated with 0:5 g (95% CI: 0.0, 1.0), 0:9 g (95% CI: 0.1, 1.7), and 1:4 g (95% CI: 0.4, 2.5) larger RV mass among former smokers, current smokers, and persons with emphysema, respectively. No associations were found with healthy individuals or with ejection fraction. CONCLUSIONS: Alterations to RV structure may represent a mechanism by which long-term PM10-2.5 exposure increases risks for adverse respiratory and cardiovascular outcomes, especially among certain susceptible populations. [ABSTRACT FROM AUTHOR]

The sum of urinary inorganic arsenic (iAs) and methylated arsenic (monomethylarsonate and dimethylarsi-nate (DMA)) species is the main biomarker of iAs exposure. Assessing iAs exposure, however, is difficult in populations with moderate-to-high seafood intakes. In the present study, we used subsamples from the Multi-Ethnic Study of Atherosclerosis (2000-2002) (n = 310) and the 2003-2006 National Health and Nutrition Examination Survey (n = 1,175). We calibrated urinary concentrations of non-seafood-derived iAs, DMA, and methylarsonate, as well as the sum of inorganic and methylated arsenic species, in the Multi-Ethnic Study of Atherosclerosis and of DMA in the National Health and Nutrition Examination Survey by regressing their original concentrations by arsenobetaine and extracting model residuals. To confirm that calibrated biomarkers reflected iAs exposure but not seafood intake, we compared urinary arsenic concentrations by levels of seafood and rice intakes. Self-reported seafood intakes, estimated n-3 polyunsaturated fatty acid levels, and measured n-3 polyunsaturated fatty acid levels were positively associated with the original urinary arsenic biomarkers. Using the calibrated arsenic biomarkers, we found a marked attenuation of the associations with self-reported seafood intake and estimated or measured n-3 fatty acids, whereas associations with self-reported rice intake remained similar. Our residual-based method provides estimates of iAs exposure and metabolism for each participant that no longer reflect seafood intake and can facilitate research about low-to-moderate levels of iAs exposure in populations with high seafood intakes. [ABSTRACT FROM AUTHOR]

BACKGROUND: Physical disability is common though not inevitable in older age and has direct bearing on a person's ability to perform activities essential for self-care and independent living. Air pollution appears to increase the risk of several chronic diseases that contribute to the progression of disability. OBJECTIVE: We evaluated long-term exposure to traffic-related air pollution (TRAP) in relation to progression in physical disability. METHODS: We conducted our investigation within the Chicago Health and Aging Project. We measured participants' exposures to TRAP using two surrogates: residential proximity to major roads (1993 onwards) and ambient concentrations of oxides of nitrogen (NO[sub X]; 1999 onwards), predicted via a geographic information systems-based spatiotemporal smoothing model (cross-validation R² = 0.87) that incorporated community-based monitoring and resolved intraurban exposure gradients at a spatial scale of tens of meters. Participants' lower-extremity physical ability was assessed every 3 years (1993-2012) via tandem stand, chair stand, and timed walking speed. RESULTS: In multivariable-adjusted analyses (n = 5,708), higher long-term NOX exposure was associated with significantly faster progression in disability. Compared with the 5-year decline in physical ability score among participants in the lowest quartile of NOX exposure, decline among those in the highest exposure quartile was 1.14 units greater (95% confidence interval [CI]: -1.86, -0.42), equivalent to 3 additional years of decline among those in the lowest exposure quartile. The association was linear across the continuum of NOX exposure: per 10-ppb increment in exposure, the 5-year decline in physical ability score was 0.87 unit greater (95% CI: -1.35, -0.39). Proximity to a major road was not associated with disability progression (n = 9,994). conclusions: These data join a growing body of evidence suggesting that TRAP exposures may accelerate aging-related declines in health. [ABSTRACT FROM AUTHOR]

Background: The long-term health effects of coarse particular matter (PM10–2.5) are challenging to assess because of a limited understanding of the spatial variation in PM10–2.5 mass and its chemical components. Objectives: We conducted a spatially intensive field study and developed spatial prediction models for PM10–2.5 mass and four selected species (copper, zinc, phosphorus, and silicon) in three American cities. Methods: PM10–2.5 snapshot campaigns were conducted in Chicago, Illinois; St. Paul, Minnesota; and Winston-Salem, North Carolina, in 2009 for the Multi-Ethnic Study of Atherosclerosis and Coarse Airborne Particulate Matter (MESA Coarse). In each city, samples were collected simultaneously outside the homes of approximately 40 participants over 2 weeks in the winter and/or summer. City-specific and combined prediction models were developed using land use regression (LUR) and universal kriging (UK). Model performance was evaluated by cross-validation (CV). Results: PM10–2.5 mass and species varied within and between cities in a manner that was predictable by geographic covariates. City-specific LUR models generally performed well for total mass (CV R2, 0.41–0.68), copper (CV R2, 0.51–0.86), phosphorus (CV R2, 0.50–0.76), silicon (CV R2, 0.48–0.93), and zinc (CV R2, 0.36–0.73). Models pooled across all cities inconsistently captured within-city variability. Little difference was observed between the performance of LUR and UK models in predicting concentrations. Conclusions: Characterization of fine-scale spatial variability of these often heterogeneous pollutants using geographic covariates should reduce exposure misclassification and increase the power of epidemiological studies investigating the long-term health impacts of PM10–2.5. [ABSTRACT FROM AUTHOR]