North American Fine Particulate Matter Chemical Composition for 2000-2022 from Satellites, Models, and Monitors: The Changing Contribution of Wildfires.

Air quality management benefits from an in-depth understanding of the emissions associated with, and composition of, local PM concentrations. Here, we investigate the changing role of biomass burning emissions to North American PM exposure by combining multiple satellite-, ground-, and simulation-based data sets biweekly at a 0.01° × 0.

Epidemiological studies likely need to consider PM composition even if total outdoor PM mass concentration is the exposure of interest.

Background: Outdoor fine particulate air pollution, <2.5 µm (PM) mass concentrations can be constructed through many different combinations of chemical components that have varying levels of toxicity. This poses a challenge for studies interested in estimating the health effects of total outdoor PM (i.

Understanding Reductions of PM Concentration and Its Chemical Composition in the United States: Implications for Mitigation Strategies.

Motivated by the recent tightening of the US annual standard of fine particulate matter (PM) concentrations from 12 to 9 μg/m, there is a need to understand the spatial variation and drivers of historical PM reductions. We evaluate and interpret the variability of PM reductions across the contiguous US using high-resolution estimates of PM and its chemical composition over 1998-2019, inferred from satellite observations, air quality modeling, and ground-based measurements. We separated the 3092 counties into four characteristic regions sorted by PM trends.

Effect modification by statin use status on the association between fine particulate matter (PM2.5) and cardiovascular mortality.

Background: Numerous studies have linked fine particulate matter (PM2.5) to increased cardiovascular mortality. Less is known how the PM2.

Enhancing Global Estimation of Fine Particulate Matter Concentrations by Including Geophysical Information in Deep Learning.

Global fine particulate matter (PM) assessment is impeded by a paucity of monitors. We improve estimation of the global distribution of PM concentrations by developing, optimizing, and applying a convolutional neural network with information from satellite-, simulation-, and monitor-based sources to predict the local bias in monthly geophysical PM concentrations over 1998-2019. We develop a loss function that incorporates geophysical estimates and apply it in model training to address the unrealistic results produced by mean-square-error loss functions in regions with few monitors.

Quantifying Prescribed-Fire Smoke Exposure Using Low-Cost Sensors and Satellites: Springtime Burning in Eastern Kansas.

Prescribed fires (fires intentionally set for mitigation purposes) produce pollutants, which have negative effects on human and animal health. One of the pollutants produced from fires is fine particulate matter (PM). The Flint Hills (FH) region of Kansas experiences extensive prescribed burning each spring (March-May).

Increasing Racial and Ethnic Disparities in Ambient Air Pollution-Attributable Morbidity and Mortality in the United States.

Background: Ambient nitrogen dioxide () and fine particulate matter with aerodynamic diameter () threaten public health in the US, and systemic racism has led to modern-day disparities in the distribution and associated health impacts of these pollutants.

Objectives: Many studies on environmental injustices related to ambient air pollution focus only on disparities in pollutant concentrations or provide only an assessment of pollution or health disparities at a snapshot in time. In this study, we compare injustices in and health burdens, considering health impacts across the entire US; document changing disparities in these health burdens over time (2010-2019); and evaluate how more stringent air quality standards would reduce disparities in health impacts associated with these pollutants.

Fine particulate matter composition in American Indian vs. Non-American Indian communities.

Background: Fine particulate matter (PM) exposure is a known risk factor for numerous adverse health outcomes, with varying estimates of component-specific effects. Populations with compromised health conditions such as diabetes can be more sensitive to the health impacts of air pollution exposure. Recent trends in PM in primarily American Indian- (AI-) populated areas examined in previous work declined more gradually compared to the declines observed in the rest of the US.

Reversal of trends in global fine particulate matter air pollution.

Ambient fine particulate matter (PM) is the world's leading environmental health risk factor. Quantification is needed of regional contributions to changes in global PM exposure. Here we interpret satellite-derived PM estimates over 1998-2019 and find a reversal of previous growth in global PM air pollution, which is quantitatively attributed to contributions from 13 regions.

Inequality in the Distribution of Air Pollution Attributable Mortality Within Canadian Cities.

Recent studies have identified inequality in the distribution of air pollution attributable health impacts, but to our knowledge this has not been examined in Canadian cities. We evaluated the extent and sources of inequality in air pollution attributable mortality at the census tract (CT) level in seven of Canada's largest cities. We first regressed fine particulate matter (PM) and nitrogen dioxide (NO) attributable mortality against the neighborhood (CT) level prevalence of age 65 and older, low income, low educational attainment, and identification as an Indigenous (First Nations, Métis, Inuit) or Black person, accounting for spatial autocorrelation.

Prenatal air pollution, maternal immune activation, and autism spectrum disorder.

Background: Autism Spectrum Disorder (ASD) risk is highly heritable, with potential additional non-genetic factors, such as prenatal exposure to ambient particulate matter with aerodynamic diameter < 2.5 µm (PM) and maternal immune activation (MIA) conditions. Because these exposures may share common biological effect pathways, we hypothesized that synergistic associations of prenatal air pollution and MIA-related conditions would increase ASD risk in children.

Advances in Simulating the Global Spatial Heterogeneity of Air Quality and Source Sector Contributions: Insights into the Global South.

High-resolution simulations are essential to resolve fine-scale air pollution patterns due to localized emissions, nonlinear chemical feedbacks, and complex meteorology. However, high-resolution global simulations of air quality remain rare, especially of the Global South. Here, we exploit recent developments to the GEOS-Chem model in its high-performance implementation to conduct 1-year simulations in 2015 at cubed-sphere C360 (∼25 km) and C48 (∼200 km) resolutions.

National Cohort Study of Long-Term Exposure to PM Components and Mortality in Medicare American Older Adults.

There is increasing evidence linking long-term fine particulate matter (PM) exposure to negative health effects. However, the relative influence of each component of PM on health risk is poorly understood. In a cohort study in the contiguous United States between 2000 and 2017, we examined the effect of long-term exposure to PM main components and all-cause mortality in older adults who had to be at least 65 years old and enrolled in Medicare.

A cross-sectional analysis of ambient fine particulate matter (PM) exposure and haemoglobin levels in children aged under 5 years living in 36 countries.

Low haemoglobin (Hb) concentrations and anaemia in children have adverse effects on development and functioning, some of which may have consequences in later life. Exposure to ambient air pollution is reported to be associated with anaemia, but there is little evidence specific to low- and middle-income countries (LMICs), where childhood anaemia prevalence is greatest. We aimed to determine if long-term ambient fine particulate matter (≤2.

Using Parametric g-Computation to Estimate the Effect of Long-Term Exposure to Air Pollution on Mortality Risk and Simulate the Benefits of Hypothetical Policies: The Canadian Community Health Survey Cohort (2005 to 2015).

Background: Numerous epidemiological studies have documented the adverse health impact of long-term exposure to fine particulate matter [particulate matter in aerodynamic diameter ()] on mortality even at relatively low levels. However, methodological challenges remain to consider potential regulatory intervention's complexity and provide actionable evidence on the predicted benefits of interventions. We propose the parametric g-computation as an alternative analytical approach to such challenges.

Incident dementia and long-term exposure to constituents of fine particle air pollution: A national cohort study in the United States.

Growing evidence suggests that fine particulate matter (PM) likely increases the risks of dementia, yet little is known about the relative contributions of different constituents. Here, we conducted a nationwide population-based cohort study (2000 to 2017) by integrating the Medicare Chronic Conditions Warehouse database and two independently sourced datasets of high-resolution PM major chemical composition, including black carbon (BC), organic matter (OM), nitrate (NO), sulfate (SO), ammonium (NH), and soil dust (DUST). To investigate the impact of long-term exposure to PM constituents on incident all-cause dementia and Alzheimer's disease (AD), hazard ratios for dementia and AD were estimated using Cox proportional hazards models, and penalized splines were used to evaluate potential nonlinear concentration-response (C-R) relationships.

A cross-sectional analysis of long-term exposure to ambient air pollution and cognitive development in children aged 3-4 years living in 12 low- and middle-income countries.

Exposure to ambient air pollution may affect cognitive functioning and development in children. Unfortunately, there is little evidence available for low- and middle-income countries (LMICs), where air pollution levels are highest. We analysed the association between exposure to ambient fine particulate matter (≤2.

Associations of Autism Spectrum Disorder with PM Components: A Comparative Study Using Two Different Exposure Models.

This retrospective cohort study examined associations of autism spectrum disorder (ASD) with prenatal exposure to major fine particulate matter (PM) components estimated using two independent exposure models. The cohort included 318 750 mother-child pairs with singleton deliveries in Kaiser Permanente Southern California hospitals from 2001 to 2014 and followed until age five. ASD cases during follow-up ( = 4559) were identified by ICD codes.