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Measuring students' exposure to particulate matter (PM) pollution across microenvironments and seasons using personal air monitors

Ryan, Ian; Deng, Xinlei; Thurston, George; Khwaja, Haider; Romeiko, Xiaobo; Zhang, Wangjian; Marks, Tia; Ye, Bo; Lin, Shao
Particulate matter (PM) pollution is a significant concern in public health, yet children's exposure is not adequately characterized. This study evaluated PM exposures among primary school-aged children in NYS across different microenvironments. This study helps fill existing knowledge gaps by characterizing PM exposure among this population across seasons and microenvironments. Sixty students were recruited from randomly selected public primary schools representing various socioeconomic statuses. Individual real-time exposure to PM2.5 was measured continuously using AirBeam personal monitors for 48 h. Children were consistently exposed to higher PM2.5 concentrations in the fall (median: fall = 2.84, spring = 2.31, winter = 0.90 µg/m3). At school, 2.19% of PM2.5 measurements exceeded the EPA annual fine particle standard, 12 µg/m3 (winter = 7.38%, fall = 2.39%, spring = 1.38%). In classrooms, PM1-4 concentrations were higher in spring and overnight, while PM7-10 concentrations were higher in fall and school hours. At home, 37.2% of fall measurements exceeded EPA standards (spring = 10.39%, winter = 4.37%). Overall, PM2.5 levels in classrooms and during transportation never rose above the EPA standard for any significant length of time. However, PM2.5 levels routinely exceeded these standards at home, in the fall, and the evening. More extensive studies are needed to confirm these results.
PMID: 36374344
ISSN: 1573-2959
CID: 5371502

Long-Term Exposure to Source-Specific Fine Particles and Mortality─A Pooled Analysis of 14 European Cohorts within the ELAPSE Project

Chen, Jie; Hoek, Gerard; de Hoogh, Kees; Rodopoulou, Sophia; Andersen, Zorana J; Bellander, Tom; Brandt, Jørgen; Fecht, Daniela; Forastiere, Francesco; Gulliver, John; Hertel, Ole; Hoffmann, Barbara; Hvidtfeldt, Ulla Arthur; Verschuren, W M Monique; Jöckel, Karl-Heinz; Jørgensen, Jeanette T; Katsouyanni, Klea; Ketzel, Matthias; Méndez, Diego Yacamán; Leander, Karin; Liu, Shuo; Ljungman, Petter; Faure, Elodie; Magnusson, Patrik K E; Nagel, Gabriele; Pershagen, Göran; Peters, Annette; Raaschou-Nielsen, Ole; Rizzuto, Debora; Samoli, Evangelia; van der Schouw, Yvonne T; Schramm, Sara; Severi, Gianluca; Stafoggia, Massimo; Strak, Maciej; Sørensen, Mette; Tjønneland, Anne; Weinmayr, Gudrun; Wolf, Kathrin; Zitt, Emanuel; Brunekreef, Bert; Thurston, George D
We assessed mortality risks associated with source-specific fine particles (PM2.5) in a pooled European cohort of 323,782 participants. Cox proportional hazard models were applied to estimate mortality hazard ratios (HRs) for source-specific PM2.5 identified through a source apportionment analysis. Exposure to 2010 annual average concentrations of source-specific PM2.5 components was assessed at baseline residential addresses. The source apportionment resulted in the identification of five sources: traffic, residual oil combustion, soil, biomass and agriculture, and industry. In single-source analysis, all identified sources were significantly positively associated with increased natural mortality risks. In multisource analysis, associations with all sources attenuated but remained statistically significant with traffic, oil, and biomass and agriculture. The highest association per interquartile increase was observed for the traffic component (HR: 1.06; 95% CI: 1.04 and 1.08 per 2.86 μg/m3 increase) across five identified sources. On a 1 μg/m3 basis, the residual oil-related PM2.5 had the strongest association (HR: 1.13; 95% CI: 1.05 and 1.22), which was substantially higher than that for generic PM2.5 mass, suggesting that past estimates using the generic PM2.5 exposure response function have underestimated the potential clean air health benefits of reducing fossil-fuel combustion. Source-specific associations with cause-specific mortality were in general consistent with findings of natural mortality.
PMID: 35737879
ISSN: 1520-5851
CID: 5278072

Temperature variability associations with cardiovascular and respiratory emergency department visits in Dhaka, Bangladesh

Rahman, Md Mostafijur; Garcia, Erika; Lim, Chris C; Ghazipura, Marya; Alam, Nur; Palinkas, Lawrence A; McConnell, Rob; Thurston, George
BACKGROUND:Greenhouse gas emissions are changing the Earth's climate, most directly by modifying temperatures and temperature variability (TV). Residents of low- and middle-income countries (LMICs) are likely more adversely affected, due to lack of air conditioning to compensate. To date, there is no local epidemiological evidence documenting the cardio-respiratory health effects of TV in Dhaka, Bangladesh, one of the most climate change vulnerable cities in the world. OBJECTIVES/OBJECTIVE:We assessed short-term TV associations with daily cardiovascular disease (CVD) and respiratory emergency department (ED) visits, as well as effect modification by age and season. METHODS:TV was calculated from the standard deviations of the daily minimum and maximum temperatures over exposure days. Time-series regression modeling was applied to daily ED visits for respiratory and CVD from January 2014 through December 2017. TV effect sizes were estimated after controlling for long-term trends and seasonality, day-of-week, holidays, and daily mean relative humidity and ambient temperature. RESULTS:) was associated with a 7.45% (95 %CI: 2.33%, 12.57%) increase in respiratory ED visits among patients above 50 years of age. CONCLUSION/CONCLUSIONS:This study provided novel and important evidence that cardio-pulmonary health in Dhaka is adversely affected year-round by day-to-day increases in TV, especially among older adults. TV is a key factor that should be considered in evaluating the potential human health impacts of climate change induced temperature changes.
PMID: 35533532
ISSN: 1873-6750
CID: 5214152

A hybrid satellite and land use regression model of source-specific PM2.5 and PM2.5 constituents

Rahman, Md Mostafijur; Thurston, George
Although PM2.5 mass varies in source and composition over time and space, most health effects assessment have made the inherent assumption that all PM2.5 mass has the same health implications, irrespective of composition. Nationwide estimates of source-specific PM2.5 mass and constituents at local-scale would allow for epidemiological studies and health effects assessments that consider the variability in PM2.5 characteristics in their health impact assessments. In response, we developed US models of annual exposures at the census tract level for five major PM2.5 sources (traffic, soil, coal, oil, and biomass combustion) and six trace elements (elemental carbon, sulfur, silicon, selenium, nickel, and non-soil potassium) for 2001 through 2014. We employed Absolute Factor Analysis (APCA) to derive the source-specific PM2.5 impacts at monitoring stations. Random forest algorithms that incorporated predictors derived from satellite, chemical transport model, and census tract resolution land-use data on traffic, meteorology, and emissions, which were rigorously tested by 10-fold cross-validation (CV), were then employed to estimate elemental and source-specific PM2.5 levels at non-monitoring site census-tracts over the study years. Model performances were moderate to good, with CV R2 ranging from 0.41 to 0.95. For PM2.5 sources, the highest CV R2 was attained for traffic PM2.5 (CV R2 = 0.73), followed by coal (CV R2 = 0.65), oil (CV R2 = 0.62), soil (CV R2 = 0.60), and biomass (CV R2 = 0.41). Among constituents, the CV was highest for sulfur (CV R2 = 0.95). Our analyses provided highly resolved spatial estimates of annual elemental and source-specific PM2.5 concentrations at the census-tract level, for 2001 through 2014. This dataset offers exposure estimates in support of future nationwide long-term health effects studies of source-specific PM2.5 mass and constituents, enabling epidemiological research that addresses the fact that not all particles are the same.
PMID: 35429918
ISSN: 1873-6750
CID: 5202072

Particle toxicity's role in air pollution [Comment]

Thurston, George D; Chen, Lung Chi; Campen, Matthew
[Figure: see text].
PMID: 35113686
ISSN: 1095-9203
CID: 5153772

Respiratory Emergency Department Visits Associations with Exposures to PM2.5 Mass, Constituents, and Sources in Dhaka, Bangladesh Air Pollution

Rahman, Md Mostafijur; Nahar, Kamrun; Begum, Bilkis A; Hopke, Philip K; Thurston, George D
RATIONALE/BACKGROUND:To date, there is no published local epidemiological evidence documenting the respiratory health effects of source specific air pollution in South Asia, where PM2.5 composition is different from past studies. Differences include more biomass and residue crop-burning emissions, which may have differing health implications. OBJECTIVES/OBJECTIVE:We assessed PM2.5 associations with respiratory emergency department (ED) visits in a biomass-burning dominated high pollution region, and evaluated their variability by pollution source and composition. METHODS:Time-series regression modeling was applied to daily ED visits from January 2014 through December 2017. Air pollutant effect sizes were estimated after addressing long-term trends and seasonality, day-of-week, holidays, relative humidity, ambient temperature, and the effect modification by season, age, and sex. RESULTS:PM2.5 yielded a significant association with increased respiratory ED visits [0.84% (95% CI: 0.33%, 1.35%)] per 10 μg/m3 increase. The PM2.5 health effect size varied with season, the highest being during monsoon season, when fossil-fuel combustion sources dominated exposures. Results from a source-specific health effect analysis was also consistent with fossil-fuel PM2.5 having a larger effect size per 10 μg/m3 than PM2.5 from other sources [fossil-fuel PM2.5: 2.79% (0.33% to 5.31%), biomass-burning PM2.5: 1.27% (0% to 2.54%), and other-PM2.5: 0.95% (0.06% to 1.85%)]. Age-specific associations varied, with children and older adults being disproportionately affected by the air pollution, especially by the combustion-related particles. CONCLUSIONS:This study provided novel and important evidence that respiratory health in Dhaka is significantly affected by particle air pollution, with a greater health impact by fossil-fuel combustion derived PM2.5.
PMID: 34283949
ISSN: 2325-6621
CID: 4948112

Respiratory Emergency Department Visit Associations with Exposures to Fine Particulate Matter Mass, Constituents, and Sources in Dhaka, Bangladesh Air Pollution

Rahman, Md Mostafijur; Nahar, Kamrun; Begum, Bilkis A.; Hopke, Philip K.; Thurston, George D.
ISSN: 1546-3222
CID: 5207362

Fossil fuel combustion and PM2.5 mass air pollution associations with mortality

Thurston, George D
PMID: 34974236
ISSN: 1873-6750
CID: 5106722

Cardiovascular morbidity and mortality associations with biomass- and fossil-fuel-combustion fine-particulate-matter exposures in Dhaka, Bangladesh

Rahman, Md Mostafijur; Begum, Bilkis A; Hopke, Philip K; Nahar, Kamrun; Newman, Jonathan; Thurston, George D
BACKGROUND:Fine-particulate-matter (i.e. with an aerodynamic diameter of ≤2.5 µm, PM2.5) air pollution is commonly treated as if it had 'equivalent toxicity', irrespective of the source and composition. We investigate the respective roles of fossil-fuel- and biomass-combustion particles in the PM2.5 relationship with cardiovascular morbidity and mortality using tracers of sources in Dhaka, Bangladesh. Results provide insight into the often observed levelling of the PM2.5 exposure-response curve at high-pollution levels. METHODS:A time-series regression model, adjusted for potentially confounding influences, was applied to 340 758 cardiovascular disease (CVD) emergency-department visits (EDVs) during January 2014 to December 2017, 253 407 hospital admissions during September 2013 to December 2017 and 16 858 CVD deaths during January 2014 to October 2017. RESULTS:Significant associations were confirmed between PM2.5-mass exposures and increased risk of cardiovascular EDV [0.27%, (0.07% to 0.47%)] at lag-0, hospitalizations [0.32% (0.08% to 0.55%)] at lag-0 and deaths [0.87%, (0.27% to 1.47%)] at lag-1 per 10-μg/m3 increase in PM2.5. However, the relationship of PM2.5 with morbidity and mortality effect slopes was less steep and non-significant at higher PM2.5 concentrations (during crop-burning-dominated exposures) and varied with PM2.5 source. Fossil-fuel-combustion PM2.5 had roughly a four times greater effect on CVD mortality and double the effect on CVD hospital admissions on a per-µg/m3 basis than did biomass-combustion PM2.5. CONCLUSION/CONCLUSIONS:Biomass burning was responsible for most PM2.5 air pollution in Dhaka, but fossil-fuel-combustion PM2.5 dominated the CVD adverse health impacts. Such by-source variations in the health impacts of PM2.5 should be considered in conducting ambient particulate-matter risk assessments, as well as in prioritizing air-pollution-mitigation measures and clinical advice.
PMID: 33822936
ISSN: 1464-3685
CID: 4839162

The role of fossil fuel combustion metals in PM2.5 air pollution health associations

Maciejczyk, Polina; Chen, Lung Chi; Thurston, George
In this review, we elucidate the central role played by fossil fuel combustion in the health-related effects that have been associated with inhalation of ambient fine particulate matter (PM2.5). We especially focus on individual properties and concentrations of metals commonly found in PM air pollution, as well as their sources and their adverse health effects, based on both epidemiologic and toxicological evidence. It is known that transition metals, such as Ni, V, Fe, and Cu, are highly capable of participating in redox reactions that produce oxidative stress. Therefore, particles that are enriched, per unit mass, in these metals, such as those from fossil fuel combustion, can have greater potential to produce health effects than other ambient particulate matter. Moreover, fossil fuel combustion particles also contain varying amounts of sulfur, and the acidic nature of the resulting sulfur compounds in particulate matter (e.g., as ammonium sulfate, ammonium bisulfate, or sulfuric acid) makes transition metals in particles more bioavailable, greatly enhancing the potential of fossil fuel combustion PM2.5 to cause oxidative stress and systemic health effects in the human body. In general, there is a need to further recognize particulate matter air pollution mass as a com-plex source-driven mixture, in order to more effectively quantify and regulate particle air pollution exposure health risks.
ISSN: 2073-4433
CID: 5008112