Exposure to traffic-related air pollution and risk of development of childhood asthma: A systematic review and meta-analysis

Childhood air pollution exposure is related to cognitive, educational and mental health outcomes in childhood and adolescence: A longitudinal birth cohort study

BACKGROUND

A growing body of evidence supports an association between air pollution exposure and adverse mental health outcomes, especially in adulthood however, very little is known about the effects of early life air pollution exposure during childhood. We examined longitudinal associations between the extent and timing of children's annual air pollution exposure from conception to age 10 years and a wide range of cognitive, educational and mental health outcomes in childhood and adolescence that were assessed prospectively as part of a large birth cohort study.

METHODS

We linked historical air pollution data (μg.m-3) from pregnancy to age 10 years (1976-1987) using the addresses of all cohort members (n = 1265) of the Christchurch Health and Development Study (CHDS) who were born in New Zealand in mid-1977. Latent Class Growth Mixture Models were used to characterise different trajectories of air pollution exposure from the prenatal period to age 10 years. We then examined associations between these air pollution exposure trajectories and 16 outcomes in childhood and adolescence using R Studio and Stata V18.

FINDINGS

Four air pollution exposure trajectories were identified: i) low, ii) persistently high, iii) high prenatal and postnatal, and iv) elevated pre-school exposure. While some associations were attenuated, after adjusting for a variety of covariates spanning childhood, family sociodemographic background and family functioning characteristics, several associations remained. Relative to the lowest exposure trajectory, persistently high and high prenatal and postnatal exposure were both related to attentional problems. High prenatal and postnatal was also related to higher risk of substance abuse. Elevated pre-school exposure was associated with conduct problems, lower educational attainment and substance abuse and persistently high childhood exposure increased risk of substance abuse.

CONCLUSIONS

Our study highlights potential adverse and longer-term impacts of air pollution exposure during childhood on subsequent development in later life.

Trends in childhood asthma in Denmark, Finland, Norway and Sweden

AIM

Estimate the incidence of asthma among children aged 0 to 15 years in Denmark, Finland, Norway and Sweden during 2000-2017.

METHODS

Cases of preschool asthma (up to 6 years) and school-age asthma (from 6 years) were identified through national registers using an algorithm including hospital diagnoses and prescription medicines. The respective cumulative incidence (CI) was estimated in 1-year age intervals for each country and birth year.

RESULTS

The CI of algorithm-based preschool asthma peaked for the birth cohorts 2008 or 2009 at 14.8% in Denmark, 11.0% in Finland, 15.1% in Norway and 13.7% in Sweden. For later birth cohorts, a slight decrease was observed. The CI of school-age asthma was 7.1% in Denmark, 10.5% in Finland, 9.7% in Norway and 10.2% in Sweden (children born in 2002). A slight decline over time was seen in Denmark and Norway, and a slight increase in Sweden and Finland.

CONCLUSION

Finland had a markedly lower CI of preschool asthma and Denmark lower CI of school-age asthma as estimated by prescriptions and hospital diagnoses. Preschool asthma may have plateaued in the Nordic countries. For school-age asthma trends over time varied by country. Differences in diagnostic and prescription practices may have influenced the results.

The relationship between early life course air pollution exposure and general health in adolescence in the United Kingdom

Air pollution is associated with health in childhood. However, there is limited evidence on sensitive periods during the first 18 years of life. Data were drawn from the Millennium Cohort Study, a large and nationally representative cohort born in 2000/2002. Self-reported general health was assessed at age 17; number of hospital records were derived from linked health data (Hospital Episode Statistics) for consented participants. Residential history was linked to 25 × 25 m grid resolution annual PM2.5, PM10 and NO2 maps between 2000 and 2019; year-specific air pollution exposure in 200-m buffers around postcode centroids were computed. After adjusting for individual and time-variant area-level confounders, children exposed to higher air pollution in early (2-4 y) (n = 9137; PM2.5: OR = 1.06, 95% CI: 1.01-1.11; PM10: OR = 1.05, 95% CI: 1.01-1.09; NO2: OR = 1.01, 95% CI: 1.00-1.02) and middle childhood (5-7) (n = 9171; PM2.5: OR = 1.04, 95% CI: 1.00-1.07; PM10: OR = 1.03, 95% CI: 1.01-1.06) reported worse general health at age 17. Higher PM2.5 and NO2 exposure in adolescence increased the number of hospital episodes in young adulthood. Individuals from non-White and disadvantaged backgrounds were exposed to higher levels of air pollution. Air pollution in early and middle childhood might contribute to worse general health, with ethnic minority and disadvantaged children being more exposed.

Comparison of air pollution mortality effect estimates using different long-term exposure assessment modelling methods

INTRODUCTION

Epidemiological studies have used different approaches to assess long-term exposure to ambient air pollution. Little is known about how different exposure models affect health effect estimates in these studies. The aim of this study was to compare air pollution mortality effect estimates in an administrative cohort in the Netherlands based on different exposure assessment methods for black carbon (BC), nitrogen dioxide (NO2), ultrafine particles (UFP), and particulate matter <2.5 μm (PM2.5).

METHODS

Annual average air pollution exposure estimates using eight methods, differing in modelling and monitoring strategy, were applied to a Dutch national cohort of 10.7 million adults aged ≥30 years. Dispersion and land-use regression models based on mobile and fixed-site monitoring were evaluated. Follow-up was from 2013 to 2019. Hazard ratios (HR) for natural and cause-specific mortality were estimated using Cox proportional hazards models.

RESULTS

Exposure estimates from different models were highly correlated. Even though the direction of mortality effect estimates was similar between methods, their magnitude differed substantially, e.g. the HR for BC with natural mortality ranged from 1.01 to 1.09 per increment of 1 μg/m3. No consistent differences in effect estimates were found between deterministic and empirical fixed-site and mobile models. Model predictions over a 10-year period correlated highly and resulted in similar HRs.

DISCUSSION

Different exposure models resulted in similar conclusions about the presence of associations with mortality, but HRs differed up to a ratio of 1.27. Differences in exposure assessment may therefore contribute to the observed heterogeneity of mortality estimates in systematic reviews of epidemiological studies.

Adrenergic receptor subtypes differentially influence acrolein-induced ventilatory, vascular leakage, and inflammatory responses

Adrenergic receptors (AR) are manipulated therapeutically for the treatment of pulmonary and cardiovascular diseases; however, their role in air pollutant-induced respiratory effects is poorly understood. We examined the contribution of AR-subtypes in acrolein-induced respiratory effects through selective receptor inhibition. We pre-treated 12-week-old male Wistar-Kyoto rats intraperitoneally daily for 9-days with subtype-specific AR antagonists prazosin (PRZ, α1-AR antagonist; 2-mg/kg-day), yohimbine (YOH, α2-AR antagonist; 5-mg/kg-day), or propranolol (PROP, β-AR antagonist; 10-mg/kg-day). On day-8 and day-9 of treatment, rats were exposed nose-only to air or acrolein (1.6 or 3.2 ppm), ∼4 h/day. Head-out plethysmography during exposure on Day-9 revealed overall concentration-dependent acrolein-related reduced ventilatory capacity, which was exacerbated in PRZ- and YOH-treated animals. Nasal (NALF) and bronchoalveolar lavage fluid (BALF), and blood samples were collected on day-9. Plasma epinephrine levels did not change; however, corticosterone decreased in YOH- and PROP-treated air-exposed animals. Adrenal and spleen weights were higher in PRZ-treated animals. Acrolein, 3.2-ppm depleted circulating lymphocytes in saline-treated and increased neutrophils in PRZ- and YOH-treated animals. NALF and BALF analysis indicated 3.2-ppm acrolein-induced neutrophilic and lymphocytic inflammation (NALF>BALF), which was exacerbated in lung of PRZ- and YOH-treated rats and slightly dampened in PROP-treated rats. However, acrolein-induced vascular protein leakage and increases in inflammatory cytokines in NALF were reduced by PROP-treatment. In conclusion, this study highlights sympathetically-mediated adrenoreceptor influence on acrolein-indued respiratory health effects, and AR subtype-specific modulation of breathing, hemodynamic, and inflammatory responses. These results have broader translational implications, as those receiving adrenergic agonistic/antagonistic therapies might experience variable air pollution-related respiratory health effects.

Association between short-term exposure to PM2.5 and its components and mumps incidence in Lanzhou, China

To date, a limited number of studies have assessed the impact of individual and combined PM2.5 components on mumps incidence. Between 2013 and 2019, we collected data on 6270 mumps cases in Lanzhou, along with corresponding PM2.5 and its components, to analyze their temporal and spatial distributions. A generalized additive mixed model was constructed to examine the association between PM2.5 components and mumps incidence. Additionally, Bayesian kernel machine regression was used to evaluate the combined and interactive effects of co-exposure to PM2.5 components on mumps incidence and to identify key contributing components. A significant linear correlation was found between PM2.5 and mumps incidence at lag 1 month, with a relative risk (RR) of 1.85 (95 % CI: 1.14, 3.02) for each unit increase in PM2.5 (log-transformed PM2.5 concentration). Organic matter (OM) at lag 0 and 1 month, as well as black carbon (BC) at lag 1 month, were significantly positively correlated with mumps incidence. Furthermore, the joint exposure-effect curve for PM2.5 components and mumps incidence displayed an approximate V-shape. The effects of PM2.5 and its components on mumps incidence were more pronounced during the warm season. These findings suggest a significant association between short-term exposure to PM2.5 and its components and mumps incidence in Lanzhou, with potential variations in effect depending on the specific components of PM2.5.

Implications of spatial and seasonal air pollution patterns, socioeconomic disparities, and 15-minute communities for achieving WHO air quality guidelines

Achieving WHO air pollution guidelines is critical to reduce the health burden of air pollution, which disproportionately affects socioeconomically disadvantaged populations and varies by sector, spatial distribution, and seasonal trends. This study explores the implications of sectorial and spatial-seasonal air pollution patterns, socio-economic disparities, and 15-minute communities to achieve (2021) WHO air quality guidelines for PM2.5 and NO2. The study analyses spatial-temporal patterns of air pollution in Belgium. Seasonal air pollution exposure is assessed through summer-to-winter ratios, stratified by land cover, urbanisation, and proximity to roads, and linked to socio-economic disparities using LOESS regression. A case study evaluates the mitigation potential of 15-minute communities for traffic-related air pollution, leveraging the Mobiscore tool to explore the relationship between accessibility and car ownership, a proxy for traffic-related emissions. NO2 and PM2.5 show marked seasonal and spatial variations, with higher concentration ratios in summer near busy roads and urban centres, especially for NO2. In general the NO2 spatial-seasonal pattern is more heterogenous compared to the PM2.5 pattern. Winter pollution exposure significantly hampers meeting WHO health targets, although summer levels of NO2 remain high around major traffic routes. The observed disparities in exposure to NO₂ highlight significant socio-economic inequalities, with the most deprived populations disproportionately burdened by traffic-related air pollution. The results from our case-study to mitigate traffic-related air pollution demonstrate that, up to a Mobiscore of 8.0, car ownership remains constant with increasing availability of services and public transport. From a turning point Mobiscore of 8.0, car ownerships starts to drop significantly, indicating that improving Mobiscores to very high scores ( > = 8.0) may lead to reduced car ownership and lower NO2 and PM2.5 emissions and exposure. Our study highlights important spatial-seasonal patterns in air pollution and their health implications, emphasizing the need for season-specific and structural traffic interventions to meet WHO guidelines for PM2.5 and NO2 exposure. A case study on mitigating traffic-related air pollution identifies a threshold where sufficient public transport and service accessibility lead to a reduction in car ownership. Addressing socio-economic disparities is crucial, as these areas often face greater challenges in meeting WHO air pollution guidelines, particularly for NO₂.

Sector-, Season-, and Country-Specific NO2-Associated Health Benefits from NO x Emission Reductions

Long-term exposure to NO2 is associated with elevated risks for pediatric asthma and premature death. Despite national policies targeting NO2's main source, NO x emissions, its global health burden remains high. Here, we use the air quality model GEOS-Chem adjoint with TROPOspheric Monitoring Instrument (TROPOMI)-based satellite downscaling to estimate that long-term NO2 exposure is responsible for 2.07 (95% CI 0.91-2.70) million pediatric asthma cases and 1.98 (95% CI 0.52-2.86) million deaths globally in 2019. We attribute these to anthropogenic NO x emissions by sector, country, and season using the adjoint model and provide a recommendation for the most impactful sector and season for NO x emission controls in each G20 country. Discrepancies exist between the health benefits incurred by emission reductions and the emission sector distributions, particularly in countries with emitters adjoining population centers. For example, we find that, if Russian anthropogenic NO x emissions were reduced uniformly by 10% across all sectors, the energy sector, 31% of annual NO x emissions, would account for 47% of pediatric asthma and 49% of premature death health benefits. The season in which these emission reductions occur also affects the magnitude of the health benefit, as seen by the fact that Russian wintertime NO x emission reductions alone are responsible for approximately one-third of the annual health benefits for each health outcome. We present the unique results for each of the G20 members to showcase how a country's NO x emission reductions can be most impactful in reducing the global NO2-associated health burden.

Exposure range matters: considering nonlinear associations in the meta-analysis of environmental pollutant exposure using examples of per- and polyfluoroalkyl substances and birth outcomes

Meta-analysis is a powerful analytic method for summarizing effect estimates across studies. However, conventional meta-analysis often assumes a linear exposure-outcome relationship and does not account for variability over the exposure ranges. In this work, we first used simulation techniques to illustrate that the linear-based meta-analytical approach may result in oversimplistic effect estimation based on 3 plausible nonlinear exposure-outcome curves (S-shape, inverted U-shape, and M-shape). We showed that subgroup meta-analysis that stratifies on exposure levels can investigate nonlinearity and identify the consistency of effect magnitudes in these simulated examples. Next, we examined the heterogeneity of effect estimates across exposure ranges in 2 published linear-based meta-analyses of prenatal exposure to per- and polyfluoroalkyl substances (PFAS) on changes in mean birth weight or risk of preterm birth. The reanalysis found some varying effect sizes and potential heterogeneity when restricting to different PFAS exposure ranges, but findings were sensitive to the cut-off choices used to rank the exposure levels. Finally, we discussed methodological challenges and recommendations for detecting and interpreting potential nonlinear associations in meta-analysis. Using meta-analysis without accounting for exposure range could contribute to literature inconsistency for exposure-induced health effects and impede evidence-based policymaking. Therefore, investigating result heterogeneity by exposure range is recommended. This article is part of a Special Collection on Environmental Epidemiology.

Assessing the impact of traffic restriction interventions on school air quality: a citizen science-based modelling study

Air pollution poses a significant threat to human health, especially for the vulnerable groups such as children. Given that schools are central to their daily lives, ensuring good air quality in these environments is crucial. This study evaluates the impact of traffic restriction interventions around schools by integrating citizen science monitoring data with advanced modeling techniques. From February 4 to March 4, 2023, within the framework of a citizen science project called "NO2, No Grazie!", NO2 concentrations were measured in Milan and Rome (Italy), Italy's two most populated cities, both affected by high traffic-related pollution, using passive samplers. The spatial distribution of NO2 across entire city territories was estimated using Land Use Random Forest (LURF) models. Four traffic restriction scenarios were developed alongside a business-as-usual one; furthermore, each school was characterized by the social vulnerability of its area. In total, 486 samplers were analyzed in Milan and 407 in Rome, with NO2 levels averaging 47.1 μg/m3 and 42.6 μg/m3, respectively. LURF models explained 64 % and 53 % of the measured variability, with traffic proximity as a major predictor. Among 659 schools in Milan and 1595 in Rome, all traffic restriction scenarios led to significant NO2 reductions. The most effective scenario reduced NO2 by 2.7 μg/m3 in Milan and 1.9 μg/m3 in Rome on average, with maximum observed decreases of 11.1 μg/m3 and 16.1 μg/m3, respectively. Schools in socioeconomically deprived areas had lower NO2 levels and were less impacted by the restrictions. The study underscores the value of traffic policies in improving air quality around schools.

Emerging evidence for the impact of Electric Vehicle sales on childhood asthma: Can ZEV mandates help?

Growing epidemiological studies indicate a significant fraction of asthma cases can be attributed to traffic-related air pollution (TRAP). Zero emission vehicle (ZEV) mandates - one of the most forward-looking climate policies in the United States - aim to reduce TRAP by mandating automakers to sell a certain fraction of Electric Vehicles (EVs) annually; however, their public health benefits are largely unknown. We conduct the screening step of the health impact assessment (HIA) of real-world EV sales to estimate the impact of ZEV mandates in reducing childhood asthma. Using publicly available US state and national datasets, we isolate the burden of childhood asthma attributable to TRAP from 2013 to 2019 and examine the influence of EV and non-EV vehicle sales and fleets on asthma incidence and prevalence using a generalized linear mixed model. Our analyses indicate that new EV sales have reduced asthma, with one asthma case prevented for every 264 (95% CI: 113-401) new EVs on the road. The rise of new childhood asthma cases from new car sales can be prevented when non-EV sales are replaced with EV sales at an annual market share of 21.4% (7.1-41.6%). Extending our analysis to the entire vehicle fleet, we project that when EVs reach 53.0% (35.5%-76.9%), childhood asthma due to tailpipe emissions can be eradicated completely. Screening results conclude that ZEV mandates implemented over the past decade are already exhibiting measurable public health benefits, suggesting that a broader adoption could significantly reduce the asthma burden, thus we recommend a full HIA for ZEV mandates to fully assess their potential.

Comparison of air pollution exposure assessment methods and the association with children's respiratory health

INTRODUCTION

Epidemiological studies of the associations of long-term exposure to outdoor air pollution with asthma onset and lung function in children have used different exposure assessment methods. Little is known about how these different methods affect the magnitude of the effect estimates. The aim of this study was to compare associations of long-term air pollution exposures, estimated with different exposure assessment methods, with asthma incidence and lung function.

METHODS

Eight exposure assessment methods, differing in modelling (dispersion, empirical) and monitoring strategy (fixed site, mobile), were applied to estimate annual average air pollution levels at the residential addresses of 3,687 participants of the Dutch PIAMA birth cohort. Associations of air pollution exposure with asthma and lung function were assessed and compared between methods. Heterogeneity in the associations was assessed with meta-analyses.

RESULTS

Estimated exposure levels and contrasts differed substantially between methods. Exposure estimates from the different methods were moderately to highly correlated, with Pearson correlations ranging from 0.5 to 0.9. Higher air pollution levels were consistently associated with higher asthma incidence and lower FEV1. However, the magnitude of the association differed between methods (e.g. the ORs (95 % CI) for asthma incidence ranged from 1.09 (0.99; 1.21) to 2.56 (1.50; 4.36) for BC per 1 µg/m3 increment).

CONCLUSION

Different air pollution exposure assessment methods resulted in consistent conclusions about the presence and direction of associations with asthma incidence and lung function in children, but associations differed in magnitude. Differences in exposure assessment methods may partially drive heterogeneity in associations between different studies.

The odds of developing asthma and wheeze among children and adolescents exposed to particulate matter: asystematic review and meta-analysis

BACKGROUND

Exposure to air pollution specifically particulate matter causes significant health risk to children which increases their susceptibility to respiratory diseases.

OBJECTIVES

This review aimed to pool the association between particulate matter exposure and childhood asthma and wheeze among children and adolescents.

METHODS

This review included observational study articles retrieved from electronic data bases such as PubMed, Google Scholar, Hinari, Science Direct, and Semantic Scholar from 1996 to June 17, 2024. Data were extracted and analyzed using Microsoft Excel 16 and STATA version 17, respectively. Joanna Briggs Institute evaluation criteria and I2 test statistics were used for quality and heterogeneity assessment, respectively.

RESULTS

Fourty seven studies with a total of 417,874 of children and adolescents met the inclusion criteria. The pooled odd ratio (OR) of the association between Particulate Matter with a diameter of 10 micrometers or less (PM10) and Particulate Matter with a diameter of 2.5 micrometers or less (PM2.5) with asthma were 1.04 (95% CI: 1.03-1.06, p < 0.001) with significant extreme heterogeneity (I² = 82.7%, p < 0.001) and 1.05 (95% CI 1.04-1.07, p < 0.001) with high heterogeneity (I² = 80.6%, p < 0.001) among the included studies, respectively. The overall pooled estimate indicates a statistically significant association between PM10 and wheeze, with OR of 1.06 (95% CI: 1.05, 1.07) and moderate heterogeneity among included studies (I²=57.5%, p < 0.007) where as more association was observed between PM2.5 and wheeze with OR of 1.15. (95% CI: 1.10, 1.20) with an (I² =72.8%, p < 0.001).

CONCLUSION

The findings of this systematic review and meta-analysis demonstrated a statistically significant association between exposure to both PM10 and PM2.5 and the occurrence of asthma and wheezing in children and adolescents. Both PM10 and PM2.5 are associated with increased odds of asthma and wheezing, with PM2.5 showing a stronger relationship. The significant levels of heterogeneity observed suggest variations across studies, which may be due to differences in study designs, exposure level and outcome measurement types. These findings indicate the need for strategies to reduce particle air pollution to mitigate its adverse effects on children's respiratory health.

Exploring the link between ambient PM2.5 concentrations and respiratory diseases in the elderly: a study in the Muang district of Khon Kaen, Thailand

The impact of air pollution is a major public health concern. However, there are few studies on the correlation between PM2.5 and respiratory infections. This study aimed to determine a link between PM2.5 and respiratory diseases among the elderly in Thailand. The data source for this study consisted of 43 electronic files from the Khon Kaen Provincial Health Office covering years 2020 and 2021 and surveyed a total of 43,534 people. The generalized linear mixed model (GLMM) was used to determine the adjusted odds ratio (AOR), and 95 % CI. We found that exposure to PM2.5 concentrations (in 10 μg m-3 increments) was associated with respiratory diseases (AOR: 3.98; 95 % CI [1.53-10.31]). Respondents who are male, aged less than 80 years, single, self-employed, or working as contractors, have a body mass index (BMI) not equal to the standard, have NCDs (hypertension, diabetes mellitus, and cardiovascular disease), are smokers, live in sub-districts where more than 5 % of the land is planted to sugarcane, or live in close proximity to a biomass power plant were at significantly higher risk of developing respiratory diseases (p<0.05). Therefore, environmental factors including ambient PM2.5 concentrations, the proportion of sugarcane plantation areas, and biomass power plants impact the occurrence of respiratory diseases among the elderly. Also, demographic factors and NCDs are serious issues. Systematic approaches to reducing PM2.5 levels in industrial and agricultural sectors are necessary for both the general population and vulnerable groups, including the elderly and NCD patients.

Air pollution and systemic immune biomarkers in early life: A systematic review

INTRODUCTION

Children's rapid development and immature immune systems place them at a higher risk of adverse health outcomes associated with air pollution exposure. However, the specific mechanisms in which air pollution mediates immune dysregulation in youth are poorly understood. Thus, we aimed to systematically review the available epidemiological evidence surrounding the effects of indoor and ambient air pollution exposure on systemic immune biomarkers in early life (from birth to 18 years old).

METHODS

based on PRISMA guidelines, we developed a systematic search strategy and defined inclusion and exclusion criteria to retrieve publications from PubMed, SCOPUS and Web of Science published up to August 10th, 2024. Quality assessment and evidence evaluation were also performed. Five independent reviewers participated in the process.

RESULTS

In total, 96 studies were included. We found limited evidence of a causal relationship between prenatal ambient PM2.5 and reduced T-cells (CD3+ and CD8+), as well as between postnatal PM exposure and increased IgE levels or allergic sensitization. For the rest of exposure-outcome combinations we classified the evidence as inadequate, mainly due to the limited number of studies available or the lack of consistency in the results obtained among them. This was particularly the case for indoor air pollution research, for which only 12 studies were available.

CONCLUSION

the present systematic review highlights the need for further research on the impacts of air pollution on youth's immune system. We provided recommendations for future studies in order to better understand the early subclinical and clinical effects of air pollution and the underlying biological pathways, and identify the dynamics of the innate and adaptive immune responses to environmental threats. Considering the significance of childhood immunity on health outcomes within all stages of life, and the globally extensive burden of air pollution exposure, further research on this topic should be prioritized.

All-cause hospital admissions and incidence of asthma in children in Kazakhstan: a population-based retrospective cohort study

This study describes the incidence of asthma and all-cause hospital admissions among children in Kazakhstan diagnosed between 2014 and 2021. In this retrospective cohort study, we included children aged 0-17 years diagnosed with asthma (ICD-10 codes J45.x) and registered in the Unified National Electronic Health System (UNEHS) during 2014-2021. In the outpatient asthma subgroup, we analyzed asthma incidence rates per 100,000 population and all-cause hospitalization rates per 1,000 person-years. Cox regression was used to assess hospitalization risks. The cohort included 53,463 children, 63.7% male, 47.9% aged 5-11 years, and 74.1% urban residents. The incidence rate ranged from 67.5 to 185.9 among boys and 38.2 to 115.7 among girls per 100,000 population, highest in the 5-11 age group (308-351 cases). Among 31,525 outpatients, 915 (2.8%) were hospitalized, with an incidence rate of 6.91 per 1,000 person-years. The 5-11 age group had a 2.59 times higher hospitalization risk than the 0-4 age group. Respiratory infections, allergic rhinitis, and acute rhinosinusitis were the factors associated with the highest risks of hospitalization (HRs: 14.48, 12.95, and 7.28, respectively). The insights from this study enhance our understanding of asthma in Kazakhstan and offer valuable lessons applicable to similar contexts globally.

Intercomparison of Modeled Urban-Scale Vehicle NOx and PM2.5 Emissions-Implications for Equity Assessments

Accurate characterization of emissions is essential for understanding spatiotemporal variations of air pollutants and their societal impacts, including population exposure, health outcomes, and environmental justice implications. Characterizing emissions from the transportation sector is challenging due to uncertainties in emission-producing processes and in fleet composition and activity-factors that lead to differences across modeled vehicle emissions data sets. Here, we compare four data sets─Fuel-Inventory Vehicle Emissions, Neighborhood Emission Mapping Operation, Lake Michigan Air Director Consortium-Northwestern University, and University of Vermont─over the Greater Chicago region at three shared spatial resolutions (1.0, 1.3, and 4 km2). While domain-level data set agreement is strongest at the coarsest resolution, at finer resolutions we find notable inconsistencies, particularly at local scales. At 1 km2, simulated domain total NOx emissions across the four data sets differ up to 82% (∼32-58 k tons/year), while grid cell maximum PM2.5 emissions vary up to 272% (∼1.5-5.5 tons/km2/year). Intercompared emissions data sets share similar inputs; however, divergent outcomes arise from differences in emission factors, simulated vehicle processes, and characterization of traffic data. While domain-level emission burdens among racial/ethnic subgroups are generally ranked similarly across data sets, the magnitude of relative disparities can vary up to 11%-a potentially consequential factor to consider in downstream impact analyses.

Association of exposure to ambient particulate matter with asthma in children: Systematic review and meta-analysis

Objective: To assess the association between airborne particulate matter (PM) exposure and the development of asthma in children, a systematic review and meta-analysis that included nearly 10 years of related literature was conducted. Study Design: The study investigators conducted a systematic review of relevant research articles published between March 2013 and March 2023, which were accessible through several medical literature data bases of. Random-effects meta-analyses were used to analyze the effects of PM on childhood asthma. Subgroup analyses, including exposure period, type of PM, regional factors, and study type, were also used. Odds ratio (OR) and 95% confidence intervals (CI) were used to represent the estimated effect of the population. Publication bias was assessed by using the Egger test and funnel plot. Data analyses were performed using statistical analysis software and a systematic review management tool. Results: A total of 15,365 articles were identified, of which 19 studies were included in this meta-analysis. The results showed that PM exposure was positively correlated with asthma in children, with the overall random-effects risk estimates of OR 1.10 (95% CI, 1.07-1.13). In stratified analyses, PM exposure was found to be a risk factor for the development of childhood asthma. Both prenatal and postnatal PM exposure were associated with an increased risk of asthma in children, but prenatal exposure was associated with a greater increase in risk than postnatal exposure, with an effect estimate OR of 1.21 (95% CI, 1.02-1.43). In the analysis of different PM types, the OR of PM2.5 (PM < 2.5 μm in diameter) exposure was OR 1.10 (95% CI, 1.05-1.15), and no association was found between PM10 (PM < 10 μm in diameter), coarse PM (PM with an aerodynamic diameter between 2.5 and 10 μm), and black carbon BC (diameter of 0.01-0.05 μm) exposure. In different regional analyses, the effects of PM exposure on childhood asthma risk were OR 1.15 (95% CI, 1.13-1.17) in South America and OR 1.02 (95% CI, 1.01-1.03) in Asia, but no association was found in Europe and North America. In addition, the results of different study types only found that the literature that used the time-series research method had a significant association with OR 1.03 (95% CI, 1.02-1.04), whereas the literature that used the cohort study method had no statistical difference. Conclusion: Exposure to airborne PM increased the risk of asthma in children. Both prenatal and postnatal PM exposure was associated with an increased risk of childhood asthma, but prenatal PM exposure was associated with a greater increase than postnatal PM exposure.

Mapping Source-Specific Air Pollution Exposures Using Positive Matrix Factorization Applied to Multipollutant Mobile Monitoring in Seattle, WA

Mobile monitoring strategies are increasingly used to provide fine spatial estimates of multiple air pollutant concentrations. This study demonstrates a novel approach using positive matrix factorization (PMF) applied to multipollutant mobile monitoring data to assess source-specific air pollution exposures and to estimate associated emission factors. Data were collected from one-year mobile monitoring, with an average of 26 repeated measures of size-resolved particle number counts (PNC), PM2.5, BC, NO2, and CO2 at 309 sites in Seattle from 2019 to 2020. PMF was used to characterize underlying source-related factors. The sources associated with these six factors included emissions from aviation, diesel trucks, gasoline/hybrid vehicles, oil combustion, wood combustion, and accumulation mode aerosols. Fuel-based emission factors for three transportation-related sources were also estimated. This study reveals that PNC of ultrafine particles with size <18, 18-42, and 42-178 nm was dominated by features associated with aircraft, diesel trucks, and both oil and wood combustion. Gasoline and hybrid vehicles contributed the most to CO2 and NO2 concentrations. This approach can also be extended to other metropolitan areas, enhancing the exposure assessment in epidemiology studies.

The burden of acute respiratory infection attributable to fine particulate matter brought by dust storms among children under 5 years of age in low- and middle-income countries

BACKGROUND

Long-term exposure to fine particulate matter brought by dust storms (dust PM2.5) poses a significant risk to children's health, particularly those in low- and middle-income countries (LMICs). To quantify the impact of dust PM2.5 on children, current research focuses on acute respiratory infection (ARI) as a key health outcome, given its significant contribution to child mortality. However, the relationship used to evaluate the disease burden is mainly based on the total PM2.5 concentration, neglecting the specific effect of dust PM2.5 distinct from other PM2.5.This study aimed to develop a dust-specific exposure-response function (ERF) of ARI in children <5 years of age (U5-ARI) for future risk assessments.

METHOD

We combined population data derived from the Demographic and Health Survey covering 53 LMICs, with environmental data, including the gridded concentration of dust PM2.5. ARI in children <5 years of age (U5-ARI) was the outcome of interest, which was defined by a standard questionnaire-based method. The dust PM2.5 exposure was derived from the integration of two well-recognized datasets, and matched to each participant at the community level. We analyzed the linear association between the annual average dust PM2.5 concentration and the odds of U5-ARI with logistic regression and fixed effects after adjusting for multiple covariates. We also used the spline method to develop a dust-specific ERF. Based on the function, we estimated the burden of dust-associated U5-ARI across 100 LMICs and compared it with the results from two well-established functions of total PM2.5 mass.

RESULTS

The analysis of 1,223,118 children showed that a 10 μg/m3 increase in dust PM2.5 was associated with a 7.43% (95% confidence interval [CI]: 4.77-10.15%) increase in the odds of U5-ARI. The spline model indicated that the risk of U5-ARI increased monotonically and linearly with dust PM2.5 concentration with no evident effect threshold. In 2017, based on the dust-specific ERF, across the 100 LMICs, the number of dust-associated U5-ARI was estimated to be 159,000 (95% CI: 153,000-165,000), which was consistently higher than the estimates from ERFs based on total PM2.5 mass (142,000 [95% CI: 97,000-181,000] or 114,000 [95% CI: 80,000-153,000]). The long-term dust PM2.5 exposure contributed to 12-13% of all the children affected by U5-ARI between 2000 and 2017. The geographic hotspots were the arid and populous areas of South Asia and Africa.

CONCLUSION

This study provides critical insight into the association between long-term exposure to dust PM2.5 and the health of children in LMICs, highlighting the need for specific ERFs to distinguish the adverse effects of different PM2.5 components. Personal protection during sand dust storms can be an effective intervention to safeguard the respiratory health of children.

bneR: A collaborative workflow for air pollution exposure modeling and uncertainty characterization using the Bayesian Nonparametric Ensemble

BACKGROUND

Air pollution is a major public health threat globally. Health studies, regulatory actions, and policy evaluations typically rely on air pollutant concentrations from single exposure models, assuming accurate estimations and ignoring related uncertainty. We developed a modeling framework, bneR, to apply the Bayesian Nonparametric Ensemble (BNE) prediction model that combines existing exposure models as inputs to provide air pollution estimates and their spatio-temporal uncertainty.

METHODS

The bneR modeling framework (1) harmonizes air pollutant datasets to use standardized inputs for the BNE algorithm; (2) applies the BNE algorithm to obtain the posterior predictive distribution of pollutant concentrations; and (3) generates visualizations. We applied bneR to estimate NO2 concentrations and characterize uncertainty levels at high spatio-temporal resolution (daily, 1 km2) over New York State (NYS) for 2015. We met with stakeholders and modelers to discuss bneR user-friendliness and interpretation of its estimates.

RESULTS

Using bneR, we harmonized the spatial scale of four input NO2 models (using the finer resolution, 1 km2 for BNE estimations), applied BNE to obtain the NO2 daily posterior predictive distribution, and visualized the results. Over NYS, the daily average NO2 concentration was 6.0 (interquartile range, IQR: 4.6-6.8) pbb with daily average uncertainty (as SD) of 1.2 (IQR: 1.0-1.3) ppb. BNE performed well with cross-validated RMSE=2.84 ppb and R2=0.80.

CONCLUSION

Meeting stakeholders and modelers allowed us to understand that efficient communication on how uncertainty is estimated and interpreted is a key feature for these communities to engage in using bneR and its data products.

Long-Term Exposure to Nitrogen Dioxide and Ozone and Respiratory Health in Children

Rationale: Further evaluation of the impact of long-term exposure to the gaseous air pollutants nitrogen dioxide (NO2) and ozone (O3) on child lung function and of NO2 or O3 on eosinophilic airway inflammation is needed. Objectives: To determine whether NO2 and O3 are associated with lung function and fractional exhaled nitric oxide (FeNO) in children. Methods: We measured lung function (forced expiratory volume in 1 second [FEV1] and forced vital capacity [FVC]) at midchildhood (mean age, 7.9 yr; n = 703), early teens (13.2 yr; n = 976), and midteens (17.6 yr; n = 624) study visits, and FeNO at the early and midteens study visits in Project Viva, a cohort of mother-child pairs in the Boston area. Long-term exposure to NO2 and O3 was estimated at the home address using geospatial models. We examined associations of home address NO2 and O3 exposure and proximity to roadway with lung function and FeNO using linear regression models, adjusting for age, sex, height, weight, season, relative humidity, temperature, parental smoking, and measures of socioeconomic status. We examined for effect modification of the midteen associations by blood eosinophil concentration, physical activity, aeroallergen sensitization, and parental atopy. Results: Median exposure to NO2 was 33.1 ppb (interquartile range [IQR], 10.4 ppb) and to O3 was 35.3 ppb (IQR, 3.4) in the first year of life. Exposure to NO2 was associated with lower FEV1 and FVC across all age groups and exposure time intervals: For example, an IQR increment of NO2 exposure from birth through the early teen visit was associated with 189.9 ml lower FEV1 (95% confidence interval, -273.3, -106.5) at the midteen visit. Lifetime NO2 exposure at was associated with higher FeNO at the early teen visit: for example, 16.2% higher FeNO (95% confidence interval, 7.1-26.4%) per IQR of lifetime NO2 through the early teen visit. O3 exposure was not associated with lung function or FeNO. Aeroallergen sensitization (measured in a subset of participants) modified associations of NO2 and O3 with FeNO. Conclusions: Exposure to NO2 was associated with lower lung function and higher FeNO among generally healthy children and teenagers. Because NO2 exposure levels were within the annual U.S. Environmental Protection Agency standard, these findings suggest a need to reduce exposure to this pollutant to optimize child respiratory health.

Long-Term Greenness Effects of Urban Forests to Reduce PM10 Concentration: Does the Impact Benefit the Population Vulnerable to Asthma?

This study investigates the effect of urban forests in reducing particulate matter (PM) concentrations and its subsequent impact on the number of asthma care visits. Understanding the mechanisms behind the relationship between the greenness of blocking forests and the reduction in PM is crucial for assessing the associated human health benefits. This study analyzed the influencing factors for reducing long-term PM10 concentrations, utilizing the vegetation index and meteorological variables. Results showed that the reduction in PM10 began in 2011, five years after the establishment of the blocking forest. The annual mean PM10 concentrations decreased significantly, driven primarily by summer wind speed and summer Enhanced Vegetation Index (EVI), explaining approximately 62% of the variation. A decrease in the number of asthma care visits was observed, similar to the trend of PM10 reduction in the residential area and the increase in the greenness of the blocking forest. The influx of PM into the city, primarily driven by prevailing northwesterly winds, may have been mitigated by the growing blocking forest, contributing to a reduction in asthma-related medical visits among urban residents. In particular, since the onset of the COVID-19 pandemic in 2020, the increase in the PM2.5/PM10 ratio in residential areas has become more closely linked to the increase in asthma-related medical visits. It suggests another PM2.5 emission source in the residential area. The number of asthma care visits among children (under 11) and the elderly (over 65) exhibited a strong positive correlation with PM10 levels and a negative correlation with the Normalized Difference Vegetation Index (NDVI). This suggests a link between air quality improvement from the greenness of blocking forests with their capacity to capture PM and respiratory health outcomes, especially for the vulnerable groups to asthma. These findings highlight the need to manage pollutant sources such as transportation and the heating system in residential areas beyond industrial emissions as the point pollution source. The management policies have to focus on protecting vulnerable populations, such as children and the elderly, by implementing small-sized urban forests to adsorb the PM2.5 within the city and establishing blocking forests to prevent PM10 near the industrial complex.

Effects of fine particulate matter and its chemical constituents on influenza-like illness in Guangzhou, China

BACKGROUND

Although the link between fine particulate matter (PM2.5) and influenza-like illness (ILI) is well established, the effect of the chemical constituents of PM2.5 on ILI remains unclear. This study aims to explore this effect in Guangzhou, China.

METHODS

Daily data on ILI cases, PM2.5 levels, and specific PM2.5 constituents (black carbon [BC], chlorine [Cl-], ammonia [NH4+], nitrate [NO3-], and sulfate [SO42-]) in Guangzhou, China, were collected for the period of 2014-2019. Additionally, data on gaseous pollutants and meteorological conditions were obtained. By using quasi-Poisson regression models, the association between exposure to PM2.5 and its constituents and ILI risk was estimated. Stratified subgroup analyses were performed by gender, age, and season to explore in depth the effects of these factors on disease risk.

RESULTS

Single-pollutant modeling results showed that an increase of one interquartile range (IQR) in Cl-, SO42-, PM2.5, NH4+, BC, and NO3- corresponded to relative risks of ILI of 1.046 (95 % CI: 1.004, 1.090) (lag03), 1.098 (95 % CI: 1.058, 1.139) (lag01), 1.091 (95 % CI: 1.054, 1.130) (lag02), 1.093 (95 % CI: 1.049, 1.138) (lag02), 1.111 (95 % CI: 1.074, 1.150) (lag03), and 1.103 (95 % CI: 1.061, 1.146) (lag03), respectively. Notably, the association between ILI and BC remained significant even after adjusting for PM2.5 mass. Subgroup analyses indicated that individuals aged 5-14 and 15-24 years may exhibit higher sensitivity to BC and Cl- exposure than other individuals. Furthermore, stronger associations were observed during the cold season than during the warm season.

CONCLUSIONS

Results showed that the mass and constituents of PM2.5 were significantly correlated with ILI. Specifically, the carbonaceous fractions of PM2.5 were found to have a pronounced effect on ILI. These findings underscore the importance of implementing effective measures to reduce the emission of specific sources of PM2.5 constituents to mitigate the risk of ILI. Nevertheless, limitations such as potential exposure misclassification and regional constraints should be considered.

Gene-Air Pollution Interaction and Diversity of Genetic Sampling: The Southern California Children's Health Study

Gene-environment interactions have been observed for childhood asthma, however few have been assessed in ethnically diverse populations. Thus, we examined how polygenic risk score (PRS) modifies the association between ambient air pollution exposure (nitrogen dioxide [NO2], ozone, particulate matter < 2.5 and < 10 μm) and childhood asthma incidence in a diverse cohort. Participants (n = 1794) were drawn from the Southern California Children's Health Study, a multi-wave prospective cohort followed from 4th to 12th grade. PRS was developed using single nucleotide polymorphisms previously associated with childhood asthma. PRS-asthma associations and PRS-air pollutant interactions were estimated using Poisson regression. An interquartile range PRS increase was associated with 36% (95% CI: 9%, 70%) higher asthma incidence among non-Hispanic children, but not associated with asthma among Hispanic children (rate ratio: 0.81 [95% CI: 0.62, 1.04]). NO2-PRS interaction was borderline significant in the overall sample (coefficient: 0.23 [95% CI: -0.03, 0.49]). Limited evidence was observed for a positive interaction between PRS and NO2 exposure associated with asthma incidence; however, the literature-based PRS was not associated with asthma among Hispanic participants. Equitable, diverse genetic sampling approaches are needed to better identify clinically relevant SNPs in this population.

Cell-free DNA methylation signatures reflect the risk of vascular endothelial cell injury associated with traffic-related air pollution

Traffic-related air pollution (TRAP) contains a plethora of hazardous pollutants, and is associated with a multitude of adverse health effects. However, up to now, no early biomarkers that can quickly reflect the health damage induced by TRAP. We conducted a randomized crossover trial in 35 healthy adults. Each subject was exposed to high- and low- levels of TRAP by walking in the park and along the side road leading to the freeway (road). The cardiopulmonary function parameters were measured before and after each walk session, and blood was collected 2 h after the two sessions. The present study revealed an intriguing phenomenon: the cardiac function was preferentially damaged by acute TRAP exposure. Then, we investigated the extent of damage to various human cells from exposure to TRAP by the technology of cell-of-origin of plasma cell-free DNA. Consequently, we found that only the cell-specific DNA methylation level of endothelial cells (EC) was elevated after exposure to TRAP (road) in comparison with the control (park), indicating that TRAP exposure primarily damages the EC. EC is an integral part of the cardiovascular system. This evidence indicated that TRAP exposure primarily damaged the cardiac function, compared with the other functions. Based on the cell-specific gene database of EC, we found higher levels of DNA methylation in the exon region after exposure to the TRAP session compared with the control session. Meanwhile, we also found that TRAP exposure could induce an elevated level of NACC2 in plasma, suggesting that plasma NACC2 could serve as a potential biomarker for damage of EC induced by TRAP exposure. This study suggests that the first target cell type damaged by TRAP is EC, and that the expression of NACC2 and its DNA methylation level in plasma may be a useful biomarker reflecting TRAP exposure-induced EC damage.

Estimating the potential health effects of cleaner air in the initial stages of the COVID-19 pandemic: a study in Malmö, Sweden

BACKGROUND

During the initial phase of the COVID-19 pandemic, reductions in air pollution were globally observed owing to decreased human activities, underscoring the potential for cleaner air through shifts in human behaviour.

OBJECTIVES

The objective of the present study was to hypothetically estimate the resulting population health impacts in Malmö, Sweden, if these improvements in air quality were to become permanent.

METHODS

We utilized air pollution data from two measurement campaigns conducted in the spring of 2019 and the spring of 2020 for our Health Impact Assessment, applying standard methods. This assessment involved making assumptions about baseline population risk and using established concentration-response functions.

RESULTS

In the spring of 2020, the NO2 concentrations exhibited an average decrease of 6.6 μg/m3 (42%) decrease and PM2.5 concentrations a 1.9 μg/m3 (22%) decrease, compared to the spring of 2019. If sustained, such improvements could lead to an estimated 1-3% decrease in premature deaths, a 2% decrease in preeclampsia cases, a 6% decrease in low birthweight children, a 4% decrease in bronchitis cases among children, a 2% decrease in asthma cases, a 0.2% decrease in hospital admissions for respiratory diagnoses, and an estimated 11% decrease in dementia cases annually.

CONCLUSION

The findings illustrate the potential for enhanced health in Malmö due to improved air quality. Efforts to combat air pollution and implement long-term strategies, such as those targeting urban mobility and commuting patterns, are essential for the health and well-being of both local and global populations.

Urban environment and children's health: An umbrella review of exposure response functions for health impact assessment

BACKGROUND

Urban settlements have become the main living environment. Understanding the impact of urban exposures on human health has therefore become a growing area of research. Up-to-date knowledge about the influence of urban exposures on pregnant women's and children's health is especially relevant, as they are particularly vulnerable to certain external influences.

AIM

This review aims to provide a synthesis of systematic reviews with meta-analyses reporting on an association between the urban environmental risk factors and health outcomes in pregnancy, infants, children and adolescents.

METHODS

We conducted an umbrella review, methodically analysing systematic reviews with meta-analyses, published between January 2016 and December 2022 in PubMed or Scopus. Adhering to the PRISMA checklist, we searched for free text using Medical Subject Headings (MeSH) terms related to air pollution, noise pollution, temperature, green space exposure, built and food environment, health outcomes, children (aged 0-18 years), pregnancy and systematic reviews with meta-analyses. We extracted key characteristics of each included study and assessed the quality of the included studies via the R-AMSTAR 2 tool.

RESULTS

Twenty-four studies met our inclusion criteria and identified 104 associations including 15 exposures and 60 health outcomes. The most frequently studied associations were related to air pollutants, followed by the built and food environment and noise. Birth outcomes (including low birth weight, pre-term birth or stillbirth) were the most commonly affected health outcomes, followed by respiratory outcomes such as asthma or respiratory infections. A total of 45 exposure-response function were reported to be statistically significant, including 10 exposures and 23 health effects.

CONCLUSION

This umbrella review provides an overview of the evidence and availability of exposure response functions between selected urban exposures and child health outcomes. This helps to identify research gaps and to build the basis for health impact assessment.

Variation in the Impact of New York on Pause on Traffic Congestion by Racialized Economic Segregation and Environmental Burden

During the 2019 coronavirus pandemic, stay-at-home policies such as New York's (NY) NY on Pause dramatically reduced traffic congestion. Despite high traffic burden in NY's environmental justice communities, this reduction has not been evaluated through an environmental justice lens-our objective in this analysis. We obtained census tract-level traffic congestion data from Google traffic maps hourly for 2018-2020. We defined congestion as the percent of streets in a census tract with heavy traffic (red- or maroon-color). We used the Index of Concentration at the Extremes (ICE) to measure racialized economic segregation and the CDC's Environmental Justice Index (EJI) as a measure of combined environmental, social, and chronic disease burden. We divided census tracts into quintiles of ICE and EJI and used linear mixed models stratified by ICE and EJI quintile in an interrupted time series design. Prior to NY on Pause, less marginalized and burdened census tracts (Q5) tended to have higher levels of traffic congestion; during NY on Pause, this trend reversed. For both ICE and EJI, more marginalized and burdened (Q1-Q2 vs. Q4-Q5) tracts had smaller absolute decreases in percent traffic congestion. For example, percent traffic congestion in ICE Q5 decreased by 7.8% (% change: -36.6%), but in Q1, it decreased by 4.2% (% change: -51.7%). NY on Pause, while protecting residents during COVID-19, may have resulted in inequitable reductions in traffic congestion. It is critical that such inequities are measured and acknowledged so that future policies to reduce traffic congestion and respond to pandemics can enhance equity.

Ambient air pollution exposure and adult asthma incidence: a systematic review and meta-analysis

BACKGROUND

Ambient (outdoor) air pollutant exposures have emerged as a plausible risk factor for incident childhood asthma. However, the effect of ambient air pollutant exposures on risk of incident adult asthma is unclear. We aimed to investigate associations between specific ambient air pollutants and the risk of incident adult asthma.

METHODS

In this systematic review and meta-analysis, we searched MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and Web of Science from inception to Nov 27, 2023. We included observational studies with the outcome of new-onset asthma during adulthood (onset at ≥18 years), and metric of exposure of ambient air pollutants (particulate matter [PM]2·5, nitrogen dioxide [NO2], ozone [O3], and sulphur dioxide [SO2]). Study data were extracted independently by two reviewers and study quality was assessed using the Newcastle-Ottawa scale. When four or more eligible studies were available for a given pollutant, we applied meta-analysis using inverse variance weighting in a random effects model to estimate pooled relative risk (RR), and used meta-regression to explore sources of heterogeneity. The protocol was registered with PROSPERO, CRD42023420139.

FINDINGS

Our search identified 1891 references. After excluding 651 (34%) duplicates and ineligible studies, we included 25 studies in the systematic review. After excluding studies with overlapping populations or reporting effect estimates that could not be pooled, we performed meta-analysis for PM2·5 (nine studies), NO2 (nine studies), and O3 (four studies). Pooled random effects RRs for incident adult asthma per 5 μg/m3 increase in PM2·5 were 1·07 (95% CI 1·01 to 1·13) and per 10 μg/m3 in NO2 were 1·11 (1·03 to 1·20). We found no significant association between increasing O3 concentration and incident adult asthma (per 60-μg/m3 increase in O3, pooled RR 1·04 [0·79 to 1·36]). We found substantial heterogeneity across studies (I2=88% for all analyses). In exploratory meta-regression, average exposure level was a significant source of heterogeneity for the pooled NO2 estimate (95% CI -0·0077 to -0·0025 per μg/m3).

INTERPRETATION

Exposure to increased ambient PM2·5 or NO2 might present an additional risk factor for incident adult asthma, although high heterogeneity among included studies warrants caution in interpretation. Evidence was inconsistent for O3 and insufficient for SO2. To increase confidence and population representation in pooled estimates, further primary investigations are necessary, ideally with aligned methodology and reporting.

FUNDING

None.

Effects of Air Pollution on Respiratory Events and Pain Crises among Children with Sickle Cell Disease in New York City

Rationale: The disease burden of sickle cell disease (SCD) is highest among U.S. Black and Hispanic populations, which are often disproportionately represented in communities with poor air quality. There are limited data on the effects of air pollution exposure and social environmental factors on health outcomes in children with SCD. Objectives: The objectives of our study were to examine the associations between air pollution exposure and acute respiratory and vaso-occlusive pain crises (VOCs) and to further study the associations when stratifying by asthma status and neighborhood disadvantages. Methods: We conducted a retrospective study, collecting data on outpatient sick and emergency department visits, hospital admissions for respiratory events (i.e., respiratory tract infections, asthma exacerbation, acute chest syndrome), and hospitalizations for VOCs among children with SCD in a tertiary care center in New York City from 2015 to 2018. Modeled data from the New York City Community Air Survey data using home addresses' estimated street-level annual average exposure to air pollution (i.e., black carbon, particulate matter with an aerodynamic diameter ≤2.5 μm, and nitrogen dioxide). The area deprivation index (ADI) continuous national ranking percentile (1-100) was used, representing a composite index for neighborhood-level social disadvantage. We further dichotomized study participants at the upper tertile (high vs. low ADI). Multivariable Poisson regression in generalized estimating equation models were used to estimate relative risks (RRs) after adjusting for potential covariates. Results: A total of 114 children with SCD were included in this study and had between one and four annual repeated measures of annual average air pollutants over a total of 425 visits. Overall, there were no significant associations between air pollution levels and acute respiratory pain crises and VOCs among children with SCD and when stratified by asthma status. We found significant interactions between air pollution levels and the continuous ADI variable on respiratory outpatient and frequent respiratory outpatient/ED visits (P < 0.1). When stratified by high ADI, increased exposure to particulate matter with an aerodynamic diameter ≤2.5 μm was significantly associated with more frequent respiratory outpatient/emergency department visits among children residing in higher ADI neighborhoods (RR [95% confidence interval], 1.13 [1.01, 1.27]; P < 0.05), but not among those in lower ADI neighborhoods. Increased exposure to nitrogen dioxide was associated with more outpatient respiratory events for children in high ADI neighborhoods (RR [95% confidence interval], 2.74 [1.24, 6.08]; P < 0.05) compared with low ADI neighborhoods. Conclusions: Air pollution exposures increased respiratory complications among children with SCD living in deprived neighborhoods.

Projected health benefits of air pollution reductions in a Swedish population

BACKGROUND

A large part of the Swedish population is exposed to higher levels of air pollution than the health-centered air quality guidelines recommended by the World Health Organization (WHO).

AIM

The aim of the study was to illustrate the potential health benefits of cleaner air in Sweden by conducting a comprehensive health impact assessment, using a population sample of 100,000 individuals representing the country's demographics.

METHODS

Exposure-response functions for various health outcomes were derived from epidemiological literature, mainly from systematic reviews and low-exposure settings. Two hypothetical scenarios were studied: a 1 µg/m3 decrease in particulate matter with an aerodynamic diameter <2.5µm (PM2.5) and nitrogen dioxide (NO2), and a reduction in PM2.5 or NO2 from average exposure corresponding to Sweden's Clean Air objectives to WHO's air quality guidelines.

RESULTS

The findings demonstrated that even a modest decrease in air pollution concentrations can yield significant health benefits. For example, reducing PM2.5 by 1 µg/m3 was projected to correspond to a 1% to 2% decrease in mortality, a 2% reduction in myocardial infarction cases, a 4% decrease in stroke incidence, a 2% decline in chronic obstructive pulmonary disease, and a 1% decreases in lung cancer and type 2 diabetes annually. Moreover, this reduction is estimated to lower childhood asthma cases, incidences of hypertension during pregnancy, and premature births by 3%, 3% and 2%, respectively, each year.

CONCLUSIONS

The results highlighted that even minor enhancements in air quality would lead to substantial improvements in public health.

Redox cell signalling triggered by black carbon and/or radiofrequency electromagnetic fields: Influence on cell death

The capacity of environmental pollutants to generate oxidative stress is known to affect the development and progression of chronic diseases. This scientific review identifies previously published experimental studies using preclinical models of exposure to environmental stress agents, such as black carbon and/or RF-EMF, which produce cellular oxidative damage and can lead to different types of cell death. We summarize in vivo and in vitro studies, which are grouped according to the mechanisms and pathways of redox activation triggered by exposure to BC and/or EMF and leading to apoptosis, necrosis, necroptosis, pyroptosis, autophagy, ferroptosis and cuproptosis. The possible mechanisms are considered in relation to the organ, cell type and cellular-subcellular interaction with the oxidative toxicity caused by BC and/or EMF at the molecular level. The actions of these environmental pollutants, which affect everyday life, are considered separately and together in experimental preclinical models. However, for overall interpretation of the data, toxicological studies must first be conducted in humans, to enable possible risks to human health to be established in relation to the progression of chronic diseases. Further actions should take pollution levels into account, focusing on the most vulnerable populations and future generations.

MOSES: a methylation-based gene association approach for unveiling environmentally regulated genes linked to a trait or disease

BACKGROUND

DNA methylation is a critical regulatory mechanism of gene expression, influencing various human diseases and traits. While traditional expression quantitative trait loci (eQTL) studies have helped elucidate the genetic regulation of gene expression, there is a growing need to explore environmental influences on gene expression. Existing methods such as PrediXcan and FUSION focus on genotype-based associations but overlook the impact of environmental factors. To address this gap, we present MOSES (methylation-based gene association), a novel approach that utilizes DNA methylation to identify environmentally regulated genes associated with traits or diseases without relying on measured gene expression.

RESULTS

MOSES involves training, imputation, and association testing. It employs elastic-net penalized regression models to estimate the influence of CpGs and SNPs (if available) on gene expression. We developed and compared four MOSES versions incorporating different methylation and genetic data: (1) cis-DNA methylation within 1 Mb of promoter regions, (2) both cis-SNPs and cis-CpGs, 3) both cis- and a part of trans- CpGs (±5Mb away) from promoter regions), and 4) long-range DNA methylation (±10 Mb away) from promoter regions. Our analysis using nasal epithelium and white blood cell data from the Epigenetic Variation and Childhood Asthma in Puerto Ricans (EVA-PR) study demonstrated that MOSES, particularly the version incorporating long-range CpGs (MOSES-DNAm 10 M), significantly outperformed existing methods like PrediXcan, MethylXcan, and Biomethyl in predicting gene expression. MOSES-DNAm 10 M identified more differentially expressed genes (DEGs) associated with atopic asthma, particularly those involved in immune pathways, highlighting its superior performance in uncovering environmentally regulated genes. Further application of MOSES to lung tissue data from idiopathic pulmonary fibrosis (IPF) patients confirmed its robustness and versatility across different diseases and tissues.

CONCLUSION

MOSES represents an innovative advancement in gene association studies, leveraging DNA methylation to capture the influence of environmental factors on gene expression. By incorporating long-range CpGs, MOSES-DNAm 10 M provides superior predictive accuracy and gene association capabilities compared to traditional genotype-based methods. This novel approach offers valuable insights into the complex interplay between genetics and the environment, enhancing our understanding of disease mechanisms and potentially guiding therapeutic strategies. The user-friendly MOSES R package is publicly available to advance studies in various diseases, including immune-related conditions like asthma.

Effects of climate and environmental factors on childhood and adolescent asthma: A systematic review based on spatial and temporal analysis evidence

BACKGROUND

Asthma is a prevalent chronic respiratory disease among children, influenced by various climate and environmental factors. Despite its prevalence, the specific effects of these factors on asthma remain unclear. This study aims to systematically assess the epidemiological evidence using spatial and temporal methods on the impact of climate and environmental factors on childhood asthma.

METHODS

A systematic review was conducted to analyse the impact of climate and environmental factors on childhood asthma and wheezing, focusing on spatial and temporal trends. Searches were carried out in PubMed, Embase, and CINAHL databases for studies published from January 2000 to April 2024, using key search terms 'asthma/wheezing', 'extreme weather, 'green space', 'air pollution' and 'spatial or temporal analyses".

RESULTS

The systematic review analysed 28 studies, with six employing spatial and 22 using temporal analysis methods; however, none incorporated spatio-temporal analysis in their models. The findings reveal that extreme weather events, including heatwaves and heavy rainfall, elevate childhood asthma risks across various climates, with significant effects observed during summer and winter months. Dust storms in arid and subtropical regions are linked to immediate spikes in hospital admissions due to asthma exacerbations. The effects of green spaces on childhood asthma are mixed, with some studies indicating protective effects while others suggest increased risks, influenced by local environmental factors. Air pollutants such as PM2.5, NO2, and ozone can exacerbate asthma symptoms and along with other environmental factors, contribute to seasonal effects. High temperatures generally correlate with increased asthma risks, though the effects vary by age, sex, and climate.

CONCLUSION

Future research should integrate spatial and temporal methods to better understand the effects of environmental and climate changes on childhood asthma.

Influence of Oil and Gas End-Use on Summertime Particulate Matter and Ozone Pollution in the Eastern US

The influence of oil and gas end-use activities on ambient air quality is complex and understudied, particularly in regions where intensive end-use activities and large biogenic emissions of isoprene coincide. In these regions, vehicular emissions of nitrogen oxides (NOx≡NO + NO2) modulate the oxidative fate of isoprene, a biogenic precursor of the harmful air pollutants ozone, formaldehyde, and particulate matter (PM2.5). Here, we investigate the direct and indirect influence of the end-use emissions on ambient air quality. To do so, we use the GEOS-Chem model with focus on the eastern United States (US) in summer. Regional mean end-use NOx of 1.4 ppb suppresses isoprene secondary organic aerosol (OA) formation by just 0.02 μg m-3 and enhances abundance of the carcinogen formaldehyde by 0.3 ppb. Formation of other reactive oxygenated volatile organic compounds is also enhanced, contributing to end-use maximum daily mean 8-h ozone (MDA8 O3) of 8 ppb. End-use PM2.5 is mostly (67%) anthropogenic OA, followed by 20% secondary inorganic sulfate, nitrate and ammonium and 11% black carbon. These adverse effects on eastern US summertime air quality suggest potential for severe air quality degradation in regions like the tropics with year-round biogenic emissions, growing oil and gas end-use and limited environmental regulation.

Home and school pollutant exposure, respiratory outcomes, and influence of historical redlining

BACKGROUND

The discriminatory and racist policy of historical redlining in the United States during the 1930s played a role in perpetuating contemporary environmental health disparities.

OBJECTIVE

Our objectives were to determine associations between home and school pollutant exposure (fine particulate matter [PM2.5], NO2) and respiratory outcomes (Composite Asthma Severity Index, lung function) among school-aged children with asthma and examine whether associations differed between children who resided and/or attended school in historically redlined compared to non-redlined neighborhoods.

METHODS

Children ages 6 to 17 with moderate-to-severe asthma (N = 240) from 9 US cities were included. Combined home and school exposure to PM2.5 and NO2 was calculated based on geospatially assessed monthly averaged outdoor pollutant concentrations. Repeated measures of Composite Asthma Severity Index and lung function were collected.

RESULTS

Overall, 37.5% of children resided and/or attended schools in historically redlined neighborhoods. Children in historically redlined neighborhoods had greater exposure to NO2 (median: 15.4 vs 12.1 parts per billion) and closer distance to a highway (median: 0.86 vs 1.23 km), compared to those in non-redlined neighborhoods (P < .01). Overall, PM2.5 was not associated with asthma severity or lung function. However, among children in redlined neighborhoods, higher PM2.5 was associated with worse asthma severity (P < .005). No association was observed between pollutants and lung function or asthma severity among children in non-redlined neighborhoods (P > .005).

CONCLUSIONS

Our findings highlight the significance of historical redlining and current environmental health disparities among school-aged children with asthma, specifically, the environmental injustice of PM2.5 exposure and its associations with respiratory health.

Influence and distinctions of particulate matter exposure across varying etiotypes in chronic obstructive pulmonary disease (COPD) mouse model

BACKGROUND

Air pollution, notably particulate matter (PM), significantly impacts chronic respiratory disease such chronic obstructive pulmonary disease (COPD). Although asthma-COPD overlap (ACO), considered one of the COPD etiotype, is associated with greater severity in both symptoms and outcomes, effects of PM exposure remain unclear. Thus, this study aimed to evaluate impact of PM on chronic airway disease animal models.

METHODS

We established two distinct COPD etiotypes, cigarette smoking-related COPD (COPD-C) and COPD with asthma (COPD-A), using porcine pancreatic elastase (PPE) for COPD-C and a combination of PPE with ovalbumin for COPD-A. To reflect smoking influence, cigarette smoking extract was administered to both disease models. To assess impact of PM exposure, bronchoalveolar lavage fluid (BALF), proinflammatory cytokines, lung histology, and cellular damage mechanisms were analyzed.

RESULTS

In the COPD-A model, cell counts and type 2 cytokines were elevated in BALF independent of PM exposure. All models exhibited increased lung inflammation and emphysema due to PM exposure. Expression levels of apoptosis-related protein B-cell lymphoma protein 2 (Bcl-2) associated X (Bax) showed an inclination to increase with PM exposure. In the COPD-A model, decreased expression of basal nuclear factor erythroid-derived 2-like 2 (Nrf-2) and increased production of reactive oxygen species (ROS) due to PM exposure were noted.

CONCLUSION

We developed two distinct models for the etiotypes of COPD and found increased vulnerability to cell damage in COPD-A after PM exposure. Moreover, the control group displayed escalated airway inflammation and emphysema due to PM exposure, substantiating the risk of respiratory diseases.

Windows of susceptibility and joint effects of prenatal and postnatal ambient air pollution and temperature exposure on asthma and wheeze in Mexican children

INTRODUCTION

Prenatal and early-life exposure to air pollution and extreme temperatures are associated with childhood asthma and wheeze. However, potential windows of susceptibility and their sex-specific and interactive effects have not been fully elucidated. We aimed to identify critical windows of susceptibility and evaluate sex-specific effects in these associations, and evaluate exposure interactions.

METHODS

We analyzed data from 468 mother-child pairs enrolled in the PROGRESS birth cohort in Mexico City. Daily residential levels of PM2.5, NO2, and temperature were generated from our validated spatiotemporally resolved models from conception to age 4 years. Childhood asthma and wheeze outcomes were collected at 4-6 and 7-8 years. Distributed lag nonlinear models (DLNMs) were used to identify susceptible windows for prenatal weekly-specific and postnatal monthly-specific associations of air pollution and temperature with respiratory outcomes adjusting for covariates. To evaluate sex-specific effects, DLNMs were stratified. Joint effects were assessed using relative excess risk due to interaction and attributable proportion.

RESULTS

Mid-gestation was a critical window for both PM2.5 (weeks 20-28, cumulative OR: 1.18 [95% CI: 1.01, 1.37]; weeks 19-26, cumulative OR: 1.18 [95% CI: 1.02, 1.36]) and NO2 (weeks 18-25, cumulative OR: 1.16 [95% CI: 1.02, 1.31]) exposure, associated with higher odds of wheeze. Postnatal exposure to PM2.5 and NO2 during the first year of life was also linked to higher odds of wheeze. The warmer and colder temperatures showed mixed effects on respiratory outcomes. We observed a synergistic interaction between high PM2.5 and high temperature exposure during the first year of life, associated with higher odds of current wheeze. The associations of prenatal air pollution and temperature exposure with respiratory outcomes were more pronounced in males.

CONCLUSIONS

Early-life air pollution exposure contributes to the development of childhood asthma and wheeze, while exposure to temperature showed mixed associations with respiratory outcomes.

Controlled human exposures: a review and comparison of the health effects of diesel exhaust and wood smoke

One of the most pressing issues in global health is air pollution. Emissions from traffic-related air pollution and biomass burning are two of the most common sources of air pollution. Diesel exhaust (DE) and wood smoke (WS) have been used as models of these pollutant sources in controlled human exposure (CHE) experiments. The aim of this review was to compare the health effects of DE and WS using results obtained from CHE studies. A total of 119 CHE-DE publications and 25 CHE-WS publications were identified for review. CHE studies of DE generally involved shorter exposure durations and lower particulate matter concentrations, and demonstrated more potent dysfunctional outcomes than CHE studies of WS. In the airways, DE induces neutrophilic inflammation and increases airway hyperresponsiveness, but the effects of WS are unclear. There is strong evidence that DE provokes systemic oxidative stress and inflammation, but less evidence exists for WS. Exposure to DE was more prothrombotic than WS. DE generally increased cardiovascular dysfunction, but limited evidence is available for WS. Substantial heterogeneity in experimental methodology limited the comparison between studies. In many areas, outcomes of WS exposures tended to trend in similar directions to those of DE, suggesting that the effects of DE exposure may be useful for inferring possible responses to WS. However, several gaps in the literature were identified, predominantly pertaining to elucidating the effects of WS exposure. Future studies should strongly consider performing head-to-head comparisons between DE and WS using a CHE design to determine the differential effects of these exposures.

Particulate Matter-Induced Emerging Health Effects Associated with Oxidative Stress and Inflammation

Environmental pollution continues to increase with industrial development and has become a threat to human health. Atmospheric particulate matter (PM) was designated as a Group 1 carcinogen by the International Agency for Research on Cancer in 2013 and is an emerging global environmental risk factor that is a major cause of death related to cardiovascular and respiratory diseases. PM is a complex composed of highly reactive organic matter, chemicals, and metal components, which mainly cause excessive production of reactive oxygen species (ROS) that can lead to DNA and cell damage, endoplasmic reticulum stress, inflammatory responses, atherosclerosis, and airway remodeling, contributing to an increased susceptibility to and the exacerbation of various diseases and infections. PM has various effects on human health depending on the particle size, physical and chemical characteristics, source, and exposure period. PM smaller than 5 μm can penetrate and accumulate in the alveoli and circulatory system, causing harmful effects on the respiratory system, cardiovascular system, skin, and brain. In this review, we describe the relationship and mechanism of ROS-mediated cell damage, oxidative stress, and inflammatory responses caused by PM and the health effects on major organs, as well as comprehensively discuss the harmfulness of PM.

Childhood Air Pollution Exposure Associated with Self-reported Bronchitic Symptoms in Adulthood

Rationale: Few studies have examined the effects of long-term childhood air pollution exposure on adult respiratory health, including whether childhood respiratory effects underlie this relation. Objectives: To evaluate associations between childhood air pollution exposure and self-reported adult bronchitic symptoms while considering child respiratory health in the Southern California Children's Health Study. Methods: Exposures to nitrogen dioxide (NO2), ozone, and particulate matter <2.5 μm and <10 μm in diameter (PM10) assessed using inverse-distance-squared spatial interpolation based on childhood (birth to age 17 yr) residential histories. Bronchitic symptoms (bronchitis, cough, or phlegm in the past 12 mo) were ascertained via a questionnaire in adulthood. Associations between mean air pollution exposure across childhood and self-reported adult bronchitic symptoms were estimated using logistic regression. We further adjusted for childhood bronchitic symptoms and asthma to understand whether associations operated beyond childhood respiratory health impacts. Effect modification was assessed for family history of asthma, childhood asthma, and adult allergies. Measurements and Main Results: A total of 1,308 participants were included (mostly non-Hispanic White [56%] or Hispanic [32%]). At adult assessment (mean age, 32.0 yr; standard deviation [SD], 4.7), 25% reported bronchitic symptoms. Adult bronchitic symptoms were associated with NO2 and PM10 childhood exposures. Odds ratios per 1-SD increase were 1.69 (95% confidence interval, 1.14-2.49) for NO2 (SD, 11.1 ppb) and 1.51 (95% confidence interval, 1.00-2.27) for PM10 (SD, 14.2 μg/m3). Adjusting for childhood bronchitic symptoms or asthma produced similar results. NO2 and PM10 associations were modified by childhood asthma, with greater associations among asthmatic individuals. Conclusions: Childhood NO2 and PM10 exposures were associated with adult bronchitic symptoms. Associations were not explained by childhood respiratory health impacts; however, participants with childhood asthma had stronger associations.

Improved Air Quality and Asthma Incidence from School Age to Young Adulthood: A Population-based Prospective Cohort Study

Rationale: The benefits of improved air quality on asthma remain understudied. Objectives: Our aim was to investigate associations of changes in ambient air pollution with incident asthma from school age until young adulthood in an area with mostly low air pollution levels. Methods: Participants in the BAMSE (Swedish abbreviation for Children, Allergy, Environment, Stockholm, Epidemiology) birth cohort from Stockholm without asthma before the 8-year follow-up were included (N = 2,371). We estimated the association of change in individual-level air pollutant exposure (particulate matter with an aerodynamic diameter ≤ 2.5 μm [PM2.5] and ≤ 10 μm [PM10], black carbon [BC], and nitrogen oxides [NOx]) from the first year of life to the 8-year follow-up with asthma incidence from the 8-year until the 24-year follow-up. Multipollutant trajectories were identified using the group-based multivariate trajectory model. We also used parametric G-computation to quantify the asthma incidence under different hypothetical interventions regarding air pollution levels. Results: Air pollution levels at residency decreased during the period, with median reductions of 5.6% for PM2.5, 3.1% for PM10, 5.9% for BC, and 26.8% for NOx. A total of 395 incident asthma cases were identified from the 8-year until the 24-year follow-up. The odds ratio for asthma was 0.89 (95% confidence interval [CI], 0.80-0.99) for each interquartile range reduction in PM2.5 (equal to 8.1% reduction). Associations appeared less clear for PM10, BC, and NOx. Five multipollutant trajectories were identified; the largest reduction trajectory displayed the lowest odds of asthma (odds ratio, 0.55; 95% CI, 0.31-0.98) compared with the lowest reduction trajectory. If the PM2.5 exposure had not declined up to the 8-year follow-up, the hypothetical asthma incidence was estimated to have been 10.9% higher (95% CI, 0.8-20.8%). Conclusions: A decrease in PM2.5 levels during childhood was associated with a lower risk of incident asthma from school age to young adulthood in an area with relatively low air pollution levels, suggesting broad respiratory health benefits from improved air quality.

Environmental exposures associated with early childhood recurrent wheezing in the mother and child in the environment birth cohort: a time-to-event study

BACKGROUND

Antenatal factors and environmental exposures contribute to recurrent wheezing in early childhood.

AIM

To identify antenatal and environmental factors associated with recurrent wheezing in children from birth to 48 months in the mother and child in the environment cohort, using time-to-event analysis.

METHOD

Maternal interviews were administered during pregnancy and postnatally and children were followed up from birth to 48 months (May 2013-October 2019). Hybrid land-use regression and dispersion modelling described residential antenatal exposure to nitrogen dioxide (NO2) and particulate matter of 2.5 µm diameter (PM2.5). Wheezing status was assessed by a clinician. The Kaplan-Meier hazard function and Cox-proportional hazard models provided estimates of risk, adjusting for exposure to environmental tobacco smoke (ETS), maternal smoking, biomass fuel use and indoor environmental factors.

RESULTS

Among 520 mother-child pairs, 85 (16%) children, had a single wheeze episode and 57 (11%) had recurrent wheeze. Time to recurrent wheeze (42.9 months) and single wheeze (37.8 months) among children exposed to biomass cooking fuels was significantly shorter compared with children with mothers using electricity (45.9 and 38.9 months, respectively (p=0.03)). Children with mothers exposed to antenatal ETS were 3.8 times more likely to have had recurrent wheeze compared with those not exposed (adjusted HR 3.8, 95% CI 1.3 to 10.7). Mean birth month NO2 was significantly higher among the recurrent wheeze category compared with those without wheeze. NO2 and PM2.5 were associated with a 2%-4% adjusted increased wheezing risk.

CONCLUSION

Control of exposure to ETS and biomass fuels in the antenatal period is likely to delay the onset of recurrent wheeze in children from birth to 48 months.

NPCC4: Concepts and tools for envisioning New York City's futures

This chapter of the New York City Panel on Climate Change 4 (NPCC4) report discusses the many intersecting social, ecological, and technological-infrastructure dimensions of New York City (NYC) and their interactions that are critical to address in order to transition to and secure a climate-adapted future for all New Yorkers. The authors provide an assessment of current approaches to "future visioning and scenarios" across community and city-level initiatives and examine diverse dimensions of the NYC urban system to reduce risk and vulnerability and enable a future-adapted NYC. Methods for the integration of community and stakeholder ideas about what would make NYC thrive with scientific and technical information on the possibilities presented by different policies and actions are discussed. This chapter synthesizes the state of knowledge on how different communities of scholarship or practice envision futures and provides brief descriptions of the social-demographic and housing, transportation, energy, nature-based, and health futures and many other subsystems of the complex system of NYC that will all interact to determine NYC futures.

Choices of morbidity outcomes and concentration-response functions for health risk assessment of long-term exposure to air pollution

Background

Air pollution health risk assessment (HRA) has been typically conducted for all causes and cause-specific mortality based on concentration-response functions (CRFs) from meta-analyses that synthesize the evidence on air pollution health effects. There is a need for a similar systematic approach for HRA for morbidity outcomes, which have often been omitted from HRA of air pollution, thus underestimating the full air pollution burden. We aimed to compile from the existing systematic reviews and meta-analyses CRFs for the incidence of several diseases that could be applied in HRA. To achieve this goal, we have developed a comprehensive strategy for the appraisal of the systematic reviews and meta-analyses that examine the relationship between long-term exposure to particulate matter with an aerodynamic diameter smaller than 2.5 µm (PM2.5), nitrogen dioxide (NO2), or ozone (O3) and incidence of various diseases.

Methods

To establish the basis for our evaluation, we considered the causality determinations provided by the US Environmental Protection Agency Integrated Science Assessment for PM2.5, NO2, and O3. We developed a list of pollutant/outcome pairs based on these assessments and the evidence of a causal relationship between air pollutants and specific health outcomes. We conducted a comprehensive literature search using two databases and identified 75 relevant systematic reviews and meta-analyses for PM2.5 and NO2. We found no relevant reviews for long-term exposure to ozone. We evaluated the reliability of these studies using an adaptation of the AMSTAR 2 tool, which assesses various characteristics of the reviews, such as literature search, data extraction, statistical analysis, and bias evaluation. The tool's adaptation focused on issues relevant to studies on the health effects of air pollution. Based on our assessment, we selected reviews that could be credible sources of CRF for HRA. We also assessed the confidence in the findings of the selected systematic reviews and meta-analyses as the sources of CRF for HRA. We developed specific criteria for the evaluation, considering factors such as the number of included studies, their geographical distribution, heterogeneity of study results, the statistical significance and precision of the pooled risk estimate in the meta-analysis, and consistency with more recent studies. Based on our assessment, we classified the outcomes into three lists: list A (a reliable quantification of health effects is possible in an HRA), list B+ (HRA is possible, but there is greater uncertainty around the reliability of the CRF compared to those included on list A), and list B- (HRA is not recommended because of the substantial uncertainty of the CRF).

Results

In our final evaluation, list A includes six CRFs for PM2.5 (asthma in children, chronic obstructive pulmonary disease, ischemic heart disease events, stroke, hypertension, and lung cancer) and three outcomes for NO2 (asthma in children and in adults, and acute lower respiratory infections in children). Three additional outcomes (diabetes, dementia, and autism spectrum disorders) for PM2.5 were included in list B+. Recommended CRFs are related to the incidence (onset) of the diseases. The International Classification of Diseases, 10th revision codes, age ranges, and suggested concentration ranges are also specified to ensure consistency and applicability in an HRA. No specific suggestions were given for ozone because of the lack of relevant systematic reviews.

Conclusion

The suggestions formulated in this study, including CRFs selected from the available systematic reviews, can assist in conducting reliable HRAs and contribute to evidence-based decision-making in public health and environmental policy. Future research should continue to update and refine these suggestions as new evidence becomes available and methodologies evolve.

Patterns and drivers of disparities in pediatric asthma outcomes among Medicaid-enrolled children living in subsidized housing in NYC

OBJECTIVE

There are persistent disparities in pediatric asthma morbidity in the U.S. We linked claims data with information on neighborhood-level risk factors to explore drivers of asthma disparities among Medicaid-enrolled children in New York City subsidized housing.

METHODS

We constructed a cohort of Medicaid-enrolled children living in public or other subsidized housing, based on residential address, in NYC between 2016 and 2019 (n = 108,969). We examined claims-derived asthma prevalence across age and racial and ethnic groups, integrating census tract-level information and using the Bayesian Improved Surname Geocoding (BISG) algorithm to address high rates of missing data in self-reported race and ethnicity. We used inverse probability weighting (IPW) to explore the extent to which disparities persisted when exposure to asthma risk factors - related to the built environment, neighborhood poverty, and air quality - were balanced across groups. This analysis was conducted in 2022-2023.

RESULTS

Claims-derived asthma prevalence was highest among children <7 years at baseline and among non-Hispanic Black and Hispanic children. For example, among children aged 3-6 years at baseline, claims-derived prevalence was 17.3% and 18.1% among non-Hispanic Black and Hispanic children, respectively, compared to 9.3% and 9.0% among non-Hispanic White and non-Hispanic Asian American/Pacific Islander children. Using IPW to balance exposure to asthma risk factors across racial and ethnic groups attenuated, but did not eliminate, disparities in asthma prevalence.

CONCLUSIONS

We found high asthma burden among children living in subsidized housing. Modifiable place-based characteristics may be important contributors to pediatric asthma disparities.