The association of ambient air pollution and physical inactivity in the United States

Neighborhood Deprivation and Recovery Following Traumatic Brain Injury Among Older Adults

OBJECTIVE

Understanding the extent to which neighborhood impacts recovery following traumatic brain injury (TBI) among older adults could spur targeting of rehabilitation and other services to those living in more disadvantaged areas. The objective of the present study was to determine the extent to which neighborhood disadvantage influences recovery following TBI among older adults.

Setting and Participants: Community-dwelling Medicare beneficiaries aged ≥65 years hospitalized with TBI 2010-2018.

DESIGN AND MAIN MEASURES

In this retrospective cohort study, the Area Deprivation Index (ADI) was used to assess neighborhood deprivation by linking it to 9-digit beneficiary zip codes. We used national-level rankings to divide the cohort into the top 10% (highest neighborhood disadvantage), middle 11-90%, and bottom 10% (lowest neighborhood disadvantage). Recovery was operationalized as days at home, calculated by subtracting days spent in a care environment or deceased from monthly follow-up over the year post-TBI.

RESULTS

Among 13,747 Medicare beneficiaries with TBI, 1713 (12.7%) were in the lowest decile of ADI rankings and 1030 (7.6%) were in the highest decile of ADI rankings. Following covariate adjustment, beneficiaries in neighborhoods with greatest disadvantage [rate ratio (RtR) 0.96; 95% confidence interval (CI) 0.94, 0.98] and beneficiaries in middle ADI percentiles (RtR 0.98; 95% CI 0.97, 0.99) had fewer days at home per month compared to beneficiaries in neighborhoods with lowest disadvantage.

CONCLUSION

This study provides evidence that neighborhood is associated with recovery from TBI among older adults and highlights days at home as a recovery metric that is responsive to differences in neighborhood disadvantage.

Air Quality Perceptions, Awareness, and Associated Behaviors Among U.S. Adults With and Without Heart Disease

Introduction

Exposure to ambient air pollution can worsen cardiovascular disease and increase the risk of stroke, myocardial infarction, and cardiovascular disease mortality. Strategies to reduce air pollution exposure can therefore help prevent cardiovascular morbidity and mortality. This study was conducted to assess the awareness among U.S. adults of the effect of air pollution on cardiovascular health and actions individuals can take to reduce their air pollution exposure.

Methods

In May-July 2022, 4,156 adults responded to the summer wave of the 2022 ConsumerStyles survey and self-reported their heart disease status and perceptions, awareness, and behaviors about ambient air pollution and health. In 2023, the data were analyzed to generate weighted population estimates representative of noninstitutionalized U.S. adults. Associations between heart disease and responses about perceptions, awareness, and behaviors were estimated using binomial and multinomial regression methods for weighted data.

Results

Overall, 90% of the weighted population estimate of U.S. adults reported that air pollution can impact a person's health, and 44% reported that air pollution can cause or worsen heart disease. Percentages of adults reporting that air pollution can impact a person's health (prevalence ratio=1.09; 95% CI=1.06, 1.12) and that air pollution can cause or worsen heart disease (prevalence ratio=1.28; 95% CI=1.08, 1.51) were higher among adults with than without heart disease.

Conclusions

Less than half of U.S. adults are aware that air pollution affects heart disease. Improvements in awareness of the effect of air pollution on cardiovascular health and strategies to reduce exposure could help protect individuals with heart disease.

Prenatal exposure to ambient air pollution and risk of fetal overgrowth: Systematic review of cohort studies

OBJECTIVES

Fetal overgrowth has detrimental effects on both the mother and the fetus. The global issue of ambient air pollution has been found to contribute to fetal overgrowth through various pathways. This study aimed to identify the association between prenatal exposure to ambient air pollution and the risk of fetal overgrowth.

METHODS

We identified articles between January 2013 and February 2024 by searching the Web of Sciences(WoS), PubMed, Proquest, Scopus, and Google Scholar databases. Quality assessment was performed using the Newcastle Ottawa scale. This review was provided based on the PRISMA guideline and registered with PROSPERO, "CRD42023488936".

RESULTS

The search generated 1719 studies, of which 22 cohort studies were included involving 3,480,041 participants. Results on the effects of air pollutants on fetal overgrowth are inconsistent because they vary in population and geographic region. But in general, the results indicate that prenatal exposure to air pollutants, specifically PM2.5, NO2, and SO2, is linked to a higher likelihood of fetal overgrowth(macrosomia and large for gestational age). Nevertheless, the relationship between CO and O3 pollution and fetal overgrowth remains uncertain. Furthermore, PM10 has a limited effect on fetal overgrowth. It is essential to consider the time that reproductive-age women are exposed to air pollution. Exposure to air pollutants before conception and throughout pregnancy has a substantial impact on the fetus's vulnerability to overgrowth.

CONCLUSIONS

Fetal overgrowth has implications for the health of both mother and fetus. fetal overgrowth can cause cardiovascular diseases, obesity, type 2 diabetes, and other diseases in adulthood, so it is considered an important issue for the health of the future generation. Contrary to popular belief that air pollution leads to intrauterine growth restriction and low birth weight, this study highlights that one of the adverse consequences of air pollution is macrosomia or LGA during pregnancy. Therefore governments must focus on implementing initiatives that aim to reduce pregnant women's exposure to ambient air pollution to ensure the health of future generations.

Delayed effects of air pollution on public bike-sharing system use in Seoul, South Korea: A time series analysis

BACKGROUND

As a complementary means to urban public transit systems, public bike-sharing provides a green and active mode of sustainable mobility, while reducing carbon-dioxide emissions and promoting health. There has been increasing interest in factors affecting bike-sharing usage, but little is known about the effect of ambient air pollution.

METHOD

To assess the short-term impact of daily exposure to multiple air pollutants (PM2.5, PM10, NO2, and O3) on the public bike-sharing system (PBS) usage in Seoul, South Korea (2018-2021), we applied a quasi-Poisson generalized linear model combined with a distributed lag nonlinear model (DLNM). The model was adjusted for day of the week, holiday, temperature, relative humidity, and long-term trend. We also conducted stratification analyses to examine the potential effect modification by age group, seasonality, and COVID-19.

RESULTS

We found that there was a negative association between daily ambient air pollution and the PBS usage level at a single lag day 1 (i.e., air quality a day before the event) across all four pollutants. Our results suggest that days with high levels of air pollutants (at 95th percentile) are associated with a 0.91% (0.86% to 0.96%) for PM2.5, 0.89% (0.85% to 0.94%) for PM10, 0.87% (0.82% to 0.91%) for O3, and 0.92% (0.87% to 0.98%) for NO2, reduction in cycling behavior in the next day compared to days with low levels of pollutants (at 25th percentile). No evidence of effect modification was found by seasonality, age nor the COVID-19 pandemic for any of the four pollutants.

CONCLUSIONS

Our findings suggest that high concentrations of ambient air pollution are associated with decreased rates of PBS usage on the subsequent day regardless of the type of air pollutant measured.

Objectively measured the impact of ambient air pollution on physical activity for older adults

BACKGROUND

Air pollution poses a significant health risk to the human population, especially for vulnerable groups such as the elderly, potentially discouraging their engagement in physical activity. However, there is a lack of sufficient objective and longitudinal data in current research on how air pollution affects physical activity among older adults. With these gaps, we aimed to explore the relationship between air pollution and objective measurement-based physical activity among older adults by engaging in a longitudinal study design.

METHODS

A total of 184 older adults were recruited from three cities with varying levels of air quality. Mean daily minutes of physical activity were measured with 7 consecutive days of accelerometer monitoring (ActiGraph GT3X-BT). Corresponding air pollution data including daily PM2.5 (µg/m3), PM10 (µg/m3) and air quality index (AQI) were sourced from the China National Environmental Monitoring Centre at monitor locations close to older adults' addresses. Associations between air quality and physical activity were estimated using a fixed effect model, adjusting for average daytime temperature, rain, age and weight.

RESULTS

AQI and PM2.5 were observed to exhibit significant, inverse, and linear associations with mean daily walk steps, minutes of light physical activity (LPA), moderate physical activity (MPA) and moderate-to-vigorous physical activity (MVPA) in the single variable models. A one-level increase in AQI corresponded to a decline in 550.04 steps (95% [CI] = -858.97, -241.10; p < 0.001), 10.43 min (95% [CI] = -17.07, -3.79; p < 0.001), 4.03 min (95% [CI] = -7.48, -0.59; p < 0.001) and 4.16 min (95% [CI] = -7.77, -0.56; p < 0.001) in daily walking steps, LPA, MPA, and MVPA, respectively. A one-level increase in PM2.5 correlated with a decline in daily walk steps, LPA, MPA and MVPA by 361.85 steps (95% [CI] = -516.53, -207.16; p < 0.001), 8.97 min (95% [CI] = -12.28, -5.66; p < 0.001), 3.73 min (95% [CI] = -5.46, -2.01; p < 0.001,) and 3.79 min (95% [CI] = -5.59, -1.98; p < 0.001), respectively. However, PM10 displayed a significant negative association exclusively with LPA, with one-level increase in PM10 resulting in a 3.7-minute reduction in LPA (95% [CI] = -6.81, -0.59, p < 0.05).

CONCLUSION

Air pollution demonstrates an inverse association with physical activity levels among older adults, potentially discouraging their engagement in physical activity. Different air quality indicators may exert varying impacts on physical activity. Future studies are warranted to enhance policy interventions aimed at reducing air pollution and promoting physical activity.

Exposure to Airborne PM2.5 Water-Soluble Inorganic Ions Induces a Wide Array of Reproductive Toxicity

Water-soluble inorganic ions (WSIIs, primarily NH4+, SO42-, and NO3-) are major components in ambient PM2.5, but their reproductive toxicity remains largely unknown. An animal study was conducted where parental mice were exposed to PM2.5 WSIIs or clean air during preconception and the gestational period. After delivery, all maternal and offspring mice lived in a clean air environment. We assessed reproductive organs, gestation outcome, birth weight, and growth trajectory of the offspring mice. In parallel, we collected birth weight and placenta transcriptome data from 150 mother-infant pairs from the Rhode Island Child Health Study. We found that PM2.5 WSIIs induced a broad range of adverse reproductive outcomes in mice. PM2.5 NH4+, SO42-, and NO3- exposure reduced ovary weight by 24.22% (p = 0.005), 14.45% (p = 0.048), and 16.64% (p = 0.022) relative to the clean air controls. PM2.5 SO42- exposure reduced the weight of testicle by 5.24% (p = 0.025); further, mice in the PM2.5 SO42- exposure group had 1.81 (p = 0.027) fewer offspring than the control group. PM2.5 NH4+, SO42-, and NO3- exposure all led to lower birth than controls. In mice, 557 placenta genes were perturbed by exposure. Integrative analysis of mouse and human data suggested hypoxia response in placenta as an etiological mechanism underlying PM2.5 WSII exposure's reproductive toxicity.

Effects of ambient air pollution on obesity and ectopic fat deposition: a protocol for a systematic review and meta-analysis

INTRODUCTION

Globally, the prevalence of obesity tripled from 1975 to 2016. There is evidence that air pollution may contribute to the obesity epidemic through an increase in oxidative stress and inflammation of adipose tissue. However, the impact of air pollution on body weight at a population level remains inconclusive. This systematic review and meta-analysis will estimate the association of ambient air pollution with obesity, distribution of ectopic adipose tissue, and the incidence and prevalence of non-alcoholic fatty liver disease among adults.

METHODS AND ANALYSIS

The study will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for conduct and reporting. The search will include the following databases: Ovid Medline, Embase, PubMed, Web of Science and Latin America and the Caribbean Literature on Health Sciences, and will be supplemented by a grey literature search. Each article will be independently screened by two reviewers, and relevant data will be extracted independently and in duplicate. Study-specific estimates of associations and their 95% Confidence Intervals will be pooled using a DerSimonian and Laird random-effects model, implemented using the RevMan software. The I2 statistic will be used to assess interstudy heterogeneity. The confidence in the body of evidence will be assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

ETHICS AND DISSEMINATION

As per institutional policy, ethical approval is not required for secondary data analysis. In addition to being published in a peer-reviewed journal and presented at conferences, the results of the meta-analysis will be shared with key stakeholders, health policymakers and healthcare professionals.

PROSPERO REGISTRATION NUMBER

CRD42023423955.

Associations of long-term exposure to air pollution and physical activity with the risk of systemic inflammation-induced multimorbidity in Chinese adults: results from the China multi-ethnic cohort study (CMEC)

OBJECTIVE

Previous studies proved the effect of long-term exposure to air pollution or physical activity (PA) on the risk of systemic inflammation-induced multimorbidity (SIIM), while the evidence regarding their joint effects was rare, especially in low- and middle-income countries. Therefore, we aimed to examine the extent of interaction or joint relations of PA and air pollution with SIIM.

METHODS

This study included 72,172 participants from China Multi-Ethnic Cohort.The average concentrations of ambient particulate matter pollutants (PM1, PM2.5, and PM10) were estimated using satellite-based random forest models. Self-reported information on a range of physical activities related to occupation, housework, commuting, and leisure activities was collected by an interviewer-administered questionnaire. A total of 11 chronic inflammatory systemic diseases were assessed based on self-reported lifetime diagnosis or medical examinations. SIIM was defined as having ≥ 2 chronic diseases related to systemic inflammation. Logistic regression models were used to assess the complex associations of air pollution particulate matter and PA with SIIM.

RESULTS

We found positive associations between long-term air pollution particulates exposure and SIIM, with odds ratios (95%CI) of 1.07 (1.03 to 1.11), 1.18 (1.13 to 1.24), and 1.08 (1.05 to 1.12) per 10 µg/m3 increase in PM1, PM2.5, and PM10. No significant multiplicative interaction was found between ambient air pollutant exposure and PA on SIIM, whereas negative additive interaction was observed between long-term exposure to PM2.5 and PA on SIIM. The positive associations between low volume PA and SIIM were stronger among those exposed to high-level air pollution particulates. Compared with individuals engaged in high volume PA and exposed to low-level ambient air pollutants, those engaged in low volume PA and exposed to high-level ambient air pollutants had a higher risk of SIIM (OR = 1.49 in PM1 exposure, OR = 1.84 in PM2.5 exposure, OR = 1.19 in PM10 exposure).

CONCLUSIONS

Long-term (3 years average) exposure to PM1, PM2.5, and PM10 was associated with an increased risk of SIIM. The associations were modified by PA, highlighting PA's importance in reducing SIIM for all people, especially those living in high-level air pollution regions.

Using geospatial trajectories to explore how the COVID-19 pandemic affects the associations between environmental attributes and runnability of park trails

The worldwide coronavirus disease 2019 (COVID-19) pandemic and the associated social distancing measures have produced alterations in park visits of individuals, as well as their park-based physical activity (e.g. running exercise). Although studies on the influence of the COVID-19 pandemic on changes in running activity patterns are becoming an emerging focus, less is known about how these changes are related to the environmental attributes of parks before and after the pandemic, the knowledge of which is essential to planning green infrastructure that better supports physical activities. Therefore, we employed a volunteered geographic information approach to investigate the runnability of park trails in Shenzhen, utilizing self-tracking routes from Strava, in order to uncover the associations between trail characteristics and park features with the running intensity before and after the pandemic. Multilevel regression model analyses revealed that trail network connectivity was the only environmental attribute indicating consistent and positive associations with running intensity. Blue space density was positively correlated with running intensity in urban parks but indicated no significant association in forest parks before the pandemic. In the pre-pandemic era, population density was positively related to running intensity in urban and forest parks. However, after the pandemic, the associations between running behaviours and population density remained positive in forest parks but turned insignificant in urban parks. The outbreak of the pandemic also altered the influence of other park features (e.g. park shape and trail density) on running intensity. The evidence-based knowledge provides planners with significant insights into pandemic-resilient park planning for the post-COVID era.

Impact of air pollution on the health of the older adults during physical activity and sedentary behavior: A systematic review

BACKGROUND

Air pollution, in addition to presenting health risks, can impact the practice of physical activity (PA) and sedentary behavior (SB) in older adults. This study analyzed the impact of air pollution on the health of older adults during PA and SB, through a systematic review.

METHODS

A keyword and reference search was performed in PubMed, SCOPUS, SPORTDiscus, and Web of Science. Predetermined selection criteria included study designs: interventions or experiments, retrospective or prospective cohort studies, cross-sectional studies and case-control studies; population: older adults aged 60 years or older; exposures: specific air pollutants (particulate matter (PM), nitrogen dioxide (NO2), ozone (O3), carbon monoxide (CO), sulfur dioxide (SO2), black carbon (CN), ultrafine particles (PU), nitrogen oxides (NOx) and biomass fuels) indoors and outdoors; and outcomes: physical activity and/or sedentary behavior.

RESULTS

The beneficial effects of PA were attenuated or harmed in 11 studies, showing negative impacts on the health of the older adults, mainly by PM2.5 pollutants. On the other hand, in 10 studies the effects of PA were greater than the negative effects of air pollutants, with a greater frequency in relation to PM2.5. In general, even the articles presenting controversial results suggest that practicing PA in polluted environments is more favorable to the health of older adults than remaining in SB.

DISCUSSION AND CONCLUSIONS

On the one hand, air pollution negatively impacted the health of the older adults during PA practices, while on the other hand, PA can mitigate the negative effects of pollutants on the health of older adults during the practices. Evidence shows that practicing PA in environments with low concentrations of pollutants can provide gains and reduce health risks. Remaining in SB in environments with high levels of air pollution worsens the health of older adults.

Association Between the Combined Effects of Physical Activity Intensity and Particulate Matter and All-Cause Mortality in Older Adults

OBJECTIVE

To investigate the association between the combined effects of physical activity (PA) intensity and particulate matter ≤10 μm in diameter (PM10) and mortality in older adults.

METHODS

This nationwide cohort study included older adults without chronic heart or lung disease who engaged in regular PA. Physical activity was assessed by a standardized, self-reported questionnaire that asked the usual frequency of PA sessions with low (LPA), moderate (MPA), or vigorous intensity (VPA). Each participant's annual average cumulative PM10 was categorized as low to moderate and high PM10 on the basis of a cutoff value of 90th percentile.

RESULTS

A total of 81,326 participants (median follow-up, 45 months) were included. For participants engaged in MPA or VPA sessions, every 10% increase in the proportion of VPA to total PA sessions resulted in a 4.9% (95% CI, 1.0% to 9.0%; P=.014) increased and 2.8% (95% CI, -5.0% to -0.5%; P=.018) decreased risk of mortality for those exposed to high and low to moderate PM10, respectively (Pinteraction, <.001). For participants engaged only in LPA or MPA sessions, every 10% increase in the proportion of MPA to total PA sessions resulted in a 4.8% (95% CI, -8.9% to -0.4%; P=.031) and 2.3% (95% CI, -4.2% to -0.3%; P=.023) decreased risk of mortality for those exposed to high and low to moderate PM10, respectively (Pinteraction, .096).

CONCLUSION

We found that for the same level of total PA, MPA was associated with delayed mortality whereas VPA was associated with hastened mortality of older adults in high levels of PM10.

Association of air pollution, genetic risk, and lifestyle with incident adult-onset asthma: A prospective cohort study

BACKGROUND

Numerous studies have explored the association of air pollution with asthma but have yielded conflicting results. The exact role of air pollution in the incidence of adult-onset asthma and whether this effect is modified by genetic risk, lifestyle, or their interaction remain uncertain.

METHODS

We conducted a prospective cohort study on 298,738 participants (aged 37-73 years) registered in the UK Biobank. Cox proportional hazard models were used to evaluate the association of air pollution, including particulate matter (PM_2.5, PM_coarse, and PM₁₀), nitrogen dioxide (NO₂), and nitrogen oxides (NO_x), with asthma incidence. We constructed genetic risk and lifestyle scores, assessed whether the impact of air pollution on adult-onset asthma risk was modified by genetic susceptibility or lifestyle factors, and evaluated the identified interactions.

RESULTS

We found that each interquartile range increase in annual concentrations of PM_2.5, NO₂, and NO_x was related to 1.04 (95% confidence interval [CI]: 1.01, 1.08), 1.04 (95% CI: 1.00, 1.08), and 1.03 (95% CI: 1.00, 1.06) times the risk of adult-onset asthma, respectively. The size of the effect of air pollution was greater among subpopulations with low genetic risk or unfavorable lifestyles. We also identified an additive interaction effect of air pollution with lifestyle factors, but not with genetic risk, on the risk of adult-onset asthma.

CONCLUSION

Our analyses show that air pollution increases the risk of adult-onset asthma, but that the size of the effect is modified by lifestyle and genetic risk. These findings emphasize the need for integrated interventions for environmental pollution by the government as well as adherence to healthy lifestyles to prevent adult-onset asthma.

Associations of weather and air pollution with objective physical activity and sedentary time before and after bariatric surgery: a secondary analysis of a prospective cohort study

Background--

Most metabolic and bariatric surgery (MBS) patients perform too little moderate-to-vigorous intensity physical activity (MVPA) and too much sedentary time (ST). Identifying factors that influence MVPA and ST in MBS patients is necessary to inform the development of interventions to target these behaviors. Research has focused on individual-level factors and neglected those related to the physical environment (e.g., weather and pollution). These factors may be especially important considering rapid climate change and emerging data that suggest adverse effects of weather and pollution on physical activity are more severe in people with obesity.

Objectives--

To examine the associations of weather (maximal, average and Wet Bulb Globe Temperatures), and air pollution indices (air quality index [AQI]) with daily physical activity (PA) of both light (LPA) and MVPA and ST before and after MBS.

Methods--

Participants (n=77) wore an accelerometer at pre- and 3, 6, and 12-months post-MBS to assess LPA/MVPA/ST (min/d). These data were combined with participants' local (Boston, MA or Providence, RI, USA) daily weather and AQI data (extracted from federal weather and environmental websites).

Results--

Multilevel generalized additive models showed inverted U-shaped associations between weather indices and MVPA (R2≥.63, p<.001), with a marked reduction in MVPA for daily maximal temperatures ≥20°C. Sensitivity analysis showed a less marked decrease of MVPA (min/d) during higher temperatures after versus before MBS. Both MVPA before and after MBS (R2=0.64, p<.001) and ST before MBS (R2=0.395; p≤.05) were negatively impacted by higher AQI levels.

Discussion--

This study is the first to show that weather and air pollution indices are related to variability in activity behaviors, particularly MVPA, during pre- and post-MBS. Weather/environmental conditions should be considered in MVPA prescription/strategies for MBS patients, especially in the context of climate change.

Impact of ambient air pollution on physical activity and sedentary behavior in children

BACKGROUND

Exposure to air pollution has become a serious environmental issue affecting children's health and health-related behavior in China. Previous studies have focused on the associations between air pollution and physical activity among adults; however, few have examined the relationship between air pollution and health-related behavior among children, which are particularly susceptible population subgroups. The present study aims to examine the impact of air pollution on daily physical activity (PA) and sedentary behavior (SB) among children in China.

METHODS

PA and SB data were collected by actiGraph accelerometers for eight consecutive days. PA and SB data from 206 children were matched to daily air pollution obtained from the Ministry of Environmental Protection of the People's Republic of China, including the average daily air quality index (AQI), PM_2.5 (µg/m³), and PM₁₀ (µg/m³). Associations were estimated using linear individual fixed-effect regressions.

RESULTS

A 10-unit increase in daily AQI was associated with a reduction in daily PA by 5.94 (95% confidence interval [CI] = -8.79, -3.08) minutes of moderate to vigorous physical activity (MVPA) and 229.82 (95% CI = -345.35, -114.28) walking steps and an increase in daily SB by 15.77 (95% CI = 9.01, 22.53) minutes. A 10 µg/m³ increase in air pollution concentration in daily PM_2.5 was associated with a reduction in daily PA by 7.51 (95% CI = -11.04, -3.97) minutes of MVPA, 295.69 (95% CI = -438.46, -152.92) walking steps and an increase in daily SB by 21.12 (95% CI = 12.77, 29.47) minutes. A 10 µg/m³ increase in air pollution concentration in daily PM₁₀ was associated with a reduction in daily PA by 13.18 (95% confidence interval [CI] = -15.98, -10.37) minutes of MVPA, 518.34 (95% CI = -631.77, -404.91) walking steps and an increase in daily SB by 19.87 (95% CI = 13.10, 26.64) minutes.

CONCLUSION

Air pollution may discourage physical activity and increase sedentary behavior among children. Policy interventions are needed to reduce air pollution and develop strategies to decrease risks to children's health.

Residential greenness and air pollution concerning excessive gestational weight gain during pregnancy: A cross-sectional study in Wuhan, China

BACKGROUND

Previous studies have indicated that exposure to residential greenness may benefit the health status of pregnant women, and air pollution may exert a mediating effect. Gestational weight gain (GWG) is an important indicator of pregnant women and fetuses' health and nutrition status. However, evidence concerning the impact of residential greenness on excessive gestational weight gain (EGWG) is scarce, and to what extent air pollution in urban settings mediates this relationship remains unclear.

OBJECTIVE

This study aims to explore the association of residential greenness with EGWG, consider the mediating effect of air pollution, and estimate the combined impact of residential greenness and air pollution exposures on EGWG.

METHOD

This population-based cross-sectional study involved 51,507 pregnant women with individual-level data on residential addresses in the Wuhan Maternal and Child Health Management Information System. Two spectral indexes, the normalized difference vegetation index (NDVI) and soil-adjusted vegetation index (SAVI), were used to proxy residential greenness. The air pollution data included six indicators (PM_2.5, PM₁₀, SO₂, CO, NO₂, O₃) and used the Ordinary Kriging interpolation method to estimate overall pregnancy exposure to air pollutants. Generalized linear mixed regression models were utilized to explore the relationship between residential greenness and EGWG. Restricted cubic spline (RCS) models were developed to examine the dose-response relationships. Mediation analyses explored the potential mediating role of air pollution in the residential greenness-EGWG associations. Finally, the weighted-quantile-sum (WQS) regression model was used to investigate the association between residential greenness-air pollutants co-exposure and EGWG.

RESULT

Among all participants, 26,442 had EGWG. In the adjusted model, the negative association was found significant for NDVI_100-m, NDVI_200-m, and NDVI_500-m with EGWG. For example, each IQR increase in NDVI_100-m was associated with 2.8% (95% CI: 0.6-5.0) lower odds for EGWG. The result of WQS regression showed that, when considering the six air pollutants and NDVI_-100m together, both positive and negative WQS indices were significantly associated with EGWG, PM₁₀, PM_2.5, with SO₂ having significant weights in the positive effect direction and CO, O₃, NO₂, and NDVI_100-m having a negative effect. Our results also suggested that SO₂, NO₂, PM₁₀, PM_2.5, and CO significantly mediated the association between NDVI_-100m and EGWG, and our estimates were generally robust in the sensitivity analysis.

CONCLUSION

Exposure to a higher level of residential greenness is associated with a reduced risk of EGWG, in which air pollution may exert a mediating effect. Pregnant women might benefit more in gaining healthy gestational weight when greenness levels increase from low to medium than from medium to high. Given the current cross-sectional study design, large-sale prospective cohort studies are needed to confirm our findings further.

High Levels of PM10 Reduce the Physical Activity of Professional Soccer Players

The aim of this study is to determine the impact of air quality, analyzed on the basis of the PM10 parameter in three regions of Poland, on the physical activity of soccer players from the Polish Ekstraklasa. The study material consisted of 4294 individual match observations of 362 players during the 2019/2020 domestic season. The measured indices included the parameter of air quality-PM10-and players' physical activities: total distance (TD) and high-speed running (HSR). Poland was divided into three regions (North, Central, South). The statistical analysis of particulate matter (PM) and athletes' physical activities, compared by region, revealed the effects in relation to the PM10 (H = 215.6566(2); p = 0.0001) and TD (H = 28.2682(2); p = 0.0001). Players performed better in regards to physical parameters in the North Region, where air pollution is significantly lower than in other regions. This means that even a short stay in more polluted regions can reduce the performance of professional footballers, which can indirectly affect the outcome of the match. Therefore, greater actions should be taken to improve air quality, especially through changes in daily physical activity, as this will reduce the carbon footprint.

Associations and pathways between residential greenness and metabolic syndromes in Fujian Province

Background

Greenness exposure is beneficial to human health, but its potential mechanisms through which the risk for metabolic syndrome (MetS) could be reduced have been poorly studied. We aimed to estimate the greenness-MetS association in southeast China and investigate the independent and joint mediation effects of physical activity (PA), body mass index (BMI), and air pollutants on the association.

Methods

A cross-sectional study was conducted among the 38,288 adults based on the Fujian Behavior and Disease Surveillance (FBDS), established in 2018. MetS was defined as the presence of three or more of the five components: abdominal obesity, elevated triglyceride, reduced high-density lipoprotein cholesterol (HDL-C), high blood pressure, and elevated fasting glucose. The residential greenness exposure was measured as the 3-year mean values of the normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI) within the 250, 500, and 1,000 meters (m) buffer zones around the residential address of each participant. Logistic regression models were used to estimate the greenness-MetS association. The causal mediation analysis was used to estimate the independent and joint mediation effects of PA, BMI, particulate matter with an aerodynamic diameter of 2.5 μm (PM_2.5), particulate matter with an aerodynamic diameter ≤ 10 μm (PM₁₀), nitrogen dioxide (NO₂), and sulfur dioxide (SO₂).

Results

Each interquartile range (IQR) increase in greenness was associated with a decrease of 13% (OR = 0.87 [95%CI: 0.83, 0.92] for NDVI_500m and OR = 0.87 [95%CI: 0.82, 0.91] for EVI_500m) in MetS risk after adjusting for covariates. This association was stronger in those aged < 60 years (e.g., OR = 0.86 [95%CI: 0.81, 0.92] for NDVI_500m), males (e.g., OR = 0.73 [95%CI: 0.67, 0.80] for NDVI_500m), having an educational level of primary school or above (OR = 0.81 [95%CI: 0.74, 0.89] for NDVI_500m), married/cohabitation (OR = 0.86 [95%CI: 0.81, 0.91] for NDVI_500m), businessman (OR = 0.82 [95%CI: 0.68, 0.99] for NDVI_500m), other laborers (OR = 0.77 [95%CI: 0.68, 0.88] for NDVI_500m), and non-smokers (OR = 0.77 [95%CI: 0.70, 0.85] for NDVI_500m). The joint effect of all six mediators mediated about 48.1% and 44.6% of the total effect of NDVI_500m and EVI_500m on the MetS risk, respectively. Among them, BMI showed the strongest independent mediation effect (25.0% for NDVI_500m), followed by NO₂ and PM₁₀.

Conclusion

Exposure to residential greenness was associated with a decreased risk for MetS. PA, BMI, and the four air pollutants jointly interpreted nearly half of the mediation effects on the greenness-MetS association.

Effects of Ambient Particulate Matter (PM2.5) Exposure on Calorie Intake and Appetite of Outdoor Workers

Malaysia has been experiencing smoke-haze episodes almost annually for the past few decades. PM2.5 is the main component in haze and causes harmful impacts on health due to its small aerodynamic size. This study aimed to explore the implications of PM2.5 exposure on the dietary intake of working individuals. Two phased 13-weeks follow-up study was conducted involving 440 participants, consisting of two cohorts of outdoor and indoor workers. Ambient PM2.5 concentrations were monitored using DustTrakTM DRX Aerosol Monitor. Data on Simplified Nutritional Appetite Questionnaire (SNAQ) and 24 h diet recall were collected weekly. The highest PM2.5 concentration of 122.90 ± 2.07 µg/m3 was recorded in August, and it vastly exceeded the standard value stipulated by US EPA and WHO. SNAQ scores and calorie intake were found to be significantly (p < 0.05) associated with changes in PM2.5 exposure of outdoor workers. Several moderate and positive correlations (R-value ranged from 0.4 to 0.6) were established between SNAQ scores, calorie intake and PM2.5 exposure. Overall findings suggested that long hours of PM2.5 exposure affect personal dietary intake, potentially increasing the risk of metabolic syndromes and other undesired health conditions. The current policy should be strengthened to safeguard the well-being of outdoor workers.

Is ambient air pollution associated with sarcopenia? Results from a nation-wide cross-sectional study

BACKGROUND

sarcopenia is a disease that involves the degeneration of muscle strength, muscle mass and physical performance. It remains unknown whether air pollution exposure increases the risk of sarcopenia.

METHODS

the baseline survey of the UK Biobank was used in this study. Sarcopenia was identified according to European Working Group on Sarcopenia in Older People 2 (EWGSOP2) and classified into non-sarcopenia and probable sarcopenia. Land use regressions were used to estimate concentrations of particulate matter (PM2.5), coarse particles (PMcoarse), PM10, PM2.5 absorbance, nitrogen dioxide (NO2) and nitrogen oxides (NOx). Logistic regression models were applied to estimate the associations between air pollution and sarcopenia and its components.

RESULTS

out of 352,265 participants, 28,710 (8.2%) were identified with probable sarcopenia. In adjusted models, there were increased odds of probable sarcopenia for each interquartile range increase in PM2.5 (OR: 1.06; 95% CI: 1.04, 1.07), PM10 (OR: 1.15; 95% CI: 1.13, 1.17), PMcoarse (OR: 1.02; 95% CI:1.01, 1.03), PM2.5 absorbance (OR: 1.08; 95% CI: 1.07, 1.10), NO2 (OR: 1.12; 95% CI:1.10, 1.14) and NOx (OR: 1.06; 95% CI: 1.05, 1.08).

CONCLUSIONS

this study suggests that exposure to ambient air pollution might be one risk factor of sarcopenia. Prospective studies are needed to further confirm our findings.

Association between air pollution and 24-h movement behaviours in a representative sample of Spanish youth

PURPOSE

The aim of this study was to analyse the relationship between air pollution and 24-h movement guidelines in Spanish children/adolescents.

METHODS

This cross-sectional study analysed secondary data from the Encuesta Nacional de Salud Española (2017), a representative survey for the Spanish population. The original dataset included 6016 Spanish young people (aged 0-14 years). Since the data on 24-h movement recommendations were limited to Spanish young people aged 2-14 years, the final sample included 4398 (49.2% girls) Spanish young people. Air pollution was evaluated by particulate matter 2.5 (PM_2.5) from different Spanish regions and divided into tertiles representing areas with low, medium, and high pollution. Sleep duration and recreational screen time and were reported by the parents/caregivers. Physical activity was evaluated by an adapted version of the International Physical Activity Questionnaire. Time spent in screen time, sleep, and physical activity were classified as meeting or not the 24-h movement guidelines.

RESULTS

After adjusting for several covariates (sex, age, immigrant status, region, socioeconomic status, and body mass index), lower odds of meeting with the 24-h movement recommendations were found in those living in areas with medium (odds ratio [OR] = 0.55; confident interval [CI] 95%, 0.46-0.67) or high air pollution (OR = 0.45; CI 95%, 0.36-0.55), compared with those living in areas with low air pollution.

CONCLUSIONS

The movement behaviour of young people seems to be associated with the presence of air pollution among Spanish youth. Spanish public health agencies could consider the development of strategies to mitigate the health risks for children/adolescents in high air polluted areas.

Gestational PM2.5 exposure may increase the risk of small for gestational age through maternal blood pressure and hemoglobin: A mediation analysis based on a prospective cohort in China, 2014-2018

BACKGROUND

Maternal gestational PM_2.5 exposure was associated with small for gestational age (SGA). Identifying potential mediating factors may help design preventive strategies to reduce this risk.

OBJECTIVE

This study aimed to explore the roles of maternal blood pressure and hemoglobin may play in the PM_2.5 exposure and SGA relationship among 117,162 births in 16 counties across China during 2014-2018.

METHODS

Daily PM_2.5 concentration was collected from China National Environmental Monitoring Center. According to maternal residency during pregnancy, the PM_2.5 exposure for each trimester and the whole pregnancy was assessed using an inverse-distance weighting approach. Repeated measurements of maternal blood pressure and hemoglobin during pregnancy were collected for each woman. We estimated the total effect of gestational PM_2.5 exposure on SGA, and further tested the mediation effects of maternal blood pressure and hemoglobin concentration during pregnancy.

RESULTS

Of 117,162 included mother-infant pairs, 11,361 (9.7 %) were SGA. The odds ratios of SGA associated with PM_2.5 exposure (per 10 μg/m³ increase) in the second trimester and the whole pregnancy were 1.023 (95 % CI: 1.009, 1.037) and 1.024 (1.001, 1.048), respectively. We identified the independent mediating effect of blood pressure and hemoglobin in the second and third trimesters, with the proportion of mediation ranging from 1.64 % to 5.78 % and 2.40 % to 8.70 %, respectively. When considering the mediators jointly, we found a stronger mediating effect with a proportion of mediation ranging from 3.93 % to 13.69 %.

DISCUSSION

Increases in maternal blood pressure and hemoglobin in the second and third trimesters can independently and jointly mediate the effects of gestational PM_2.5 exposure on SGA. Monitoring and managing maternal blood pressure and hemoglobin during prenatal care may constitute a promising avenue to reducing SGA risk associated with gestational PM_2.5 exposure.

Engagement in outdoor physical activity under ambient fine particulate matter pollution: A risk-benefit analysis

BACKGROUND

Outdoor physical activity (PA) brings important health benefits, but exposure to polluted air increases health risks. This study aimed to quantify the tradeoff of PA under fine particulate matter (PM2.5) air pollution by estimating the optimal PA duration under various pollution levels.

METHODS

A risk-benefit analysis was performed to estimate the optimal outdoor moderate-intensity PA (MPA) duration under varying PM2.5 concentrations.

RESULTS

An inverse nonlinear relationship was identified between optimal MPA duration and background PM2.5 concentration levels. When background PM2.5 concentration increased to 186 µg/m3, the optimal outdoor MPA duration decreased to 2.5 h/week, the minimum level recommended by current PA guidelines. When background PM2.5 concentration further increased to 235 µg/m3, the optimal outdoor MPA duration decreased to 1 h/week. The relationship between optimal MPA duration and background PM2.5 concentration levels was stronger when exercising at a location closer to a source of air pollution. Compared to the general adult population, adults aged 60 years and older had substantially steeper curves-the optimal outdoor MPA duration decreased to 2.5 h/week when background PM2.5 concentration reached 45 µg/m3.

CONCLUSION

The health benefit of outdoor MPA by far outweighs the health risk of PM2.5 pollution for the global average urban background concentration (22 μg/m3). This modeling study examined a single type of air pollutant and suffered from measurement errors and estimation uncertainties. Future research should examine other air pollutants and indoor PA, incorporate short- and mid-term health effects of MPA and air pollution into the risk-benefit analysis, and provide estimates specific for high-risk subgroups.

Spatial Disparity of Visitors Changes during Particulate Matter Warning Using Big Data Focused on Seoul, Korea

This study examined the changes in the number of visitors to regions during periods of high particulate matter (PM) concentrations in Seoul and analyzed the regional differences of these changes. Further, it examined the spatial characteristics that affect these regional differences. This study mapped the regional differences by conducting a spatial cluster analysis using GIS and examined factors affecting the regional differences using logistic regression analysis. The visiting population data used in this study were obtained from the Big Data on the de facto population measured every hour at mobile base stations, and all analyses were conducted in terms of weekdays and weekends. The results indicated that the visiting population decreases significantly on weekdays when there are high PM concentrations; however, visits increase on weekends, even during periods of high PM concentrations. Moreover, there was a huge regional gap in visiting population changes. Regions with more commercial use, higher bus accessibility, and better pedestrian environment (pedestrian paths, Walk Score) were more likely to be hotspots, whereas regions with high residential and industrial use were more likely to be cold spots. These results can be used as the basic data for PM policies based on regional characteristics.

Effectiveness of Particulate Matter Forecasting and Warning Systems within Urban Areas

The close relation between atmospheric pollution and human health has been well documented. Accordingly, various policies have been enacted worldwide to reduce and regulate air pollution, with most countries having established correlated monitoring systems. Notably in South Korea, increasing concerns about particulate matter (PM) concentrations led to the establishment of a nationwide forecasting and warning system in 2014. In this study, the PM trends in South Korea over the past decade were examined, and the correlated social issues were analyzed. In addition, the relationships between PM concentration, the forecasting–warning system, and people’s urban park use were analyzed to assess the efficacy of policy introduction. The results indicated that PM concentrations were an obstacle to outdoor activities, and the PM forecasting–warning system affected urban park use. Whereas the effects of PM forecasting and warning systems have not been sufficiently explored in practical terms in the literature, this study could be significant in proving the validity of environmental policies through the evidence including urban park visitors. This study also suggests future directions for developing PM forecasting and warning systems.

Prenatal exposure to air pollution and the risk of macrosomia: Identifying windows of susceptibility

This study explores the effects of prenatal exposure to air pollution on the risk of macrosomia and its window of susceptibility. We conducted a retrospective cohort study utilizing records of birth certificates for all full-term live newborns born in Xi'an city, China from January 1, 2015, to December 31, 2018.Weekly- and trimester-specific exposures of PM_2.5, PM₁₀, NO₂, and O₃ during pregnancy were calculated by inverse distance weighting (IDW) based on their residences. Cox proportional hazard model and distributed lag models (DLMs) were performed to estimate the effects of air pollution exposure during pregnancy on macrosomia risk and its window of susceptibility. In total, 318,323 full-term newborns were identified, including 24,996 (7.8%) cases of macrosomia. An IQR increase in PM_2.5 exposure (45.46 μg/m³) from the 33rd until the 37th weeks of gestation was positively associated with an elevated risk of macrosomia, with the strongest effect in the 37th weeks (HR = 1.007, 95%CI: 1.002-1.013). The window of susceptibility for NO₂ exposure on macrosomia risk was in the 29th-35th gestational weeks, with the strongest effect in the 34th weeks (IQR = 21.96 μg/m³, HR = 1.006, 95%CI:1.000-1.013). For prenatal exposure to O₃, 5th-24th weeks of gestation was identified as susceptible windows for elevated risk of macrosomia, with the strongest associations observed in the 15th weeks (IQR = 80.53 μg/m³, HR = 1.022, 95%CI: 1.011-1.033). However, we did not observe any associations between weekly exposure of PM₁₀ and macrosomia. Our findings imply that the windows of susceptibility to PM_2.5 and NO₂ exposure on macrosomia are mainly in late pregnancy, whereas the windows of susceptibility to O₃ exposure are in early and middle pregnancy.

Air pollution in association with mental and self-rated health and the mediating effect of physical activity

BACKGROUND

Recent studies showed that air pollution might play a role in the etiology of mental disorders. In this study we evaluated the association between air pollution and mental and self-rated health and the possible mediating effect of physical activity in this association.

METHODS

In 2008, 2013 and 2018 the Belgian Health Interview Survey (BHIS) enrolled 16,455 participants who completed following mental health dimensions: psychological distress, suboptimal vitality, suicidal ideation, and depressive and generalized anxiety disorder and self-rated health. Annual exposure to nitrogen dioxide (NO₂), particulate matter ≤ 2.5 µm (PM_2.5) and black carbon (BC) were estimated at the participants' residence by a high resolution spatiotemporal model. Multivariate logistic regressions were carried out taking into account a priori selected covariates.

RESULTS

Long-term exposure to PM_2.5, BC and NO₂ averaged 14.5, 1.4, and 21.8 µg/m³, respectively. An interquartile range (IQR) increment in PM_2.5 exposure was associated with higher odds of suboptimal vitality (OR = 1.27; 95% CI: 1.13, 1.42), poor self-rated health (OR = 1.20; 95% CI: 1.09, 1.32) and depressive disorder (OR = 1.19; 95% CI: 1.00, 1.41). Secondly, an association was found between BC exposure and higher odds of poor self-rated health and depressive and generalized anxiety disorder and between NO₂ exposure and higher odds of psychological distress, suboptimal vitality and poor self-rated health. No association was found between long-term ambient air pollution and suicidal ideation or severe psychological distress. The mediation analysis suggested that between 15.2% (PM_2.5-generalized anxiety disorder) and 40.1% (NO₂-poor self-rated health) of the association may be mediated by a difference in physical activity.

CONCLUSIONS

Long-term exposure to PM_2.5, BC or NO₂ was adversely associated with multiple mental health dimensions and self-rated health and part of the association was mediated by physical activity. Our results suggest that policies aiming to reduce air pollution levels could also reduce the burden of mental health disorders in Belgium.

Did air pollution continue to affect bike share usage in Seoul during the COVID-19 pandemic?

INTRODUCTION

The role of cycling has become more important in the urban transport system during the Covid-19 pandemic. As public transport passengers have tried to avoid crowded vehicles due to safety concerns, a rapid surge of cycling activities has been noted in many countries. This implies that more cyclists might be exposed to air pollution, potentially leading to health problems in cities like Seoul where the level of air pollution is high.

METHODS

We utilised three years of bike sharing programme (Ddareungi) data in Seoul and time series models to examine the changes in the relationship between particulate concentration (PM_2.5) and total daily cycling duration before and during the pandemic.

RESULTS

We find that cyclists reacted less to the PM_2.5 level during the pandemic, potentially due to the lack of covid-secure travel modes. Specifically, our results show significant negative associations between concentrations of PM_2.5 and total daily cycling duration before the pandemic (year 2018 and 2019). However, this association became insignificant in 2020.

CONCLUSIONS

Building comprehensive cycling infrastructure that can reduce air pollution exposure of cyclists and improving air quality alert systems could help build a more resilient city for the future.

Exposure to Outdoor Particulate Matter Air Pollution and Risk of Gastrointestinal Cancers in Adults: A Systematic Review and Meta-Analysis of Epidemiologic Evidence

BACKGROUND

Outdoor air pollution is a known lung carcinogen, but research investigating the association between particulate matter (PM) and gastrointestinal (GI) cancers is limited.

OBJECTIVES

We sought to review the epidemiologic literature on outdoor PM and GI cancers and to put the body of studies into context regarding potential for bias and overall strength of evidence.

METHODS

We conducted a systematic review and meta-analysis of epidemiologic studies that evaluated the association of fine PM [PM with an aerodynamic diameter of ≤2.5μm (PM2.5)] and PM10 (aerodynamic diameter ≤10μm) with GI cancer incidence or mortality in adults. We searched five databases for original research published from 1980 to 2021 in English and summarized findings for studies employing a quantitative estimate of exposure overall and by specific GI cancer subtypes. We evaluated the risk of bias of individual studies and the overall quality and strength of the evidence according to the Navigation Guide methodology, which is tailored for environmental health research.

RESULTS

Twenty studies met inclusion criteria and included participants from 14 countries; nearly all were of cohort design. All studies identified positive associations between PM exposure and risk of at least one GI cancer, although in 3 studies these relationships were not statistically significant. Three of 5 studies estimated associations with PM10 and satisfied inclusion criteria for meta-analysis, but each assessed a different GI cancer and were therefore excluded. In the random-effects meta-analysis of 13 studies, PM2.5 exposure was associated with an increased risk of GI cancer overall [risk ratio (RR)=1.12; 95% CI: 1.01, 1.24]. The most robust associations were observed for liver cancer (RR=1.31; 95% CI: 1.07, 1.56) and colorectal cancer (RR=1.35; 95% CI: 1.08, 1.62), for which all studies identified an increased risk. We rated most studies with "probably low" risk of bias and the overall body of evidence as "moderate" quality with "limited" evidence for this association. We based this determination on the generally positive, but inconsistently statistically significant, effect estimates reported across a small number of studies.

CONCLUSION

We concluded there is some evidence of associations between PM2.5 and GI cancers, with the strongest evidence for liver and colorectal cancers. Although there is biologic plausibility for these relationships, studies of any one cancer site were few and there remain only a small number overall. Studies in geographic areas with high GI cancer burden, evaluation of the impact of different PM exposure assessment approaches on observed associations, and investigation of cancer subtypes and specific chemical components of PM are important areas of interest for future research. https://doi.org/10.1289/EHP9620.

The Process and Platform for Predicting PM2.5 Inhalation and Retention during Exercise

In recent years, people have been increasingly concerned about air quality and pollution since a number of studies have proved that air pollution, especially PM2.5 (particulate matter), can affect human health drastically. Though the research on air quality prediction has become a mainstream research field, most of the studies focused only on the prediction of urban air quality and pollution. These studies did not predict the actual impact of these pollutants on people. According to the researchers’ best knowledge, the amount of polluted air inhaled by people and the amount of polluted air that remains inside their body are two important factors that affect their health. In order to predict the quantity of PM2.5 inhaled by people and what they have retained in their body, a process and a platform have been proposed in the current research work. In this research, the experimental process is as follows: (1) First, a personalized PM2.5 sensor is designed and developed to sense the quantity of PM2.5 around people. (2) Then, the Bruce protocol is applied to collect the information and calculate the relationship between heart rate and air intake under different activities. (3) The amount of PM2.5 retained in the body is calculated in this step using the International Commission on Radiological Protection (ICRP) air particle retention formula. (4) Then, a cloud platform is designed to collect people’s heart rate under different activities and PM2.5 values at respective times. (5) Finally, an APP is developed to show the daily intake of PM2.5. The result reveals that the developed app can show a person’s daily PM2.5 intake and retention in a specific population.

Positive Association between Indoor Gaseous Air Pollution and Obesity: An Observational Study in 60 Households

This study aims to analyze whether exposure to indoor air pollution affects obesity. In our research, we recruited 127 participants, with an average age of 43.30 ± 15.38 years old, residing in 60 households. We monitored indoor air quality for 24 h, and conducted both questionnaire surveys and collected serum samples for analysis, to assess the relationship between indoor air pollutant exposure and obesity. After adjusting for demographic characteristics, the results showed that CO₂ exposure is positively associated with being overweight and with a higher risk of being abdominally obese. Exposures to CO and formaldehyde were also positively associated with being overweight. IQR increase in TVOC was positively associated with increases in the risk of a high BMI, being abdominally obese and having a high body fat percentage. Two-pollutant models demonstrate that TVOCs presented the strongest risks associated with overweightness. We concluded that persistent exposure to indoor gaseous pollutants increases the risk of overweightness and obesity, as indicated by the positive association with BMI, abdominal obesity, and percentage body fat. TVOCs display the strongest contribution to obesity.

Ambient air pollution and movement behaviours: A scoping review

This scoping review summarizes the literature about how ambient (outdoor) air pollution impacts movement behaviours (i.e., physical activity, sedentary behaviour, and sleep), or beliefs about movement behaviours. Of 6552 potential documents, 58 documents and 218 findings were included in the final synthesis. Most studies were from the United States and China, involved cross-sectional designs, and included mixed age groups. Overall, unfavourable changes/associations (i.e., decreased/lower physical activity, increased/higher sedentary-related behaviour, and decreased/lower sleep duration and quality) or no change/association in movement behaviours in relation to ambient air pollution were identified. Our findings suggest that more attention should be given to understanding the impact of ambient air pollution on movement behaviours in general and in diverse countries and vulnerable populations such as children or older adults.

Nail Samples of Children Living near Coal Ash Storage Facilities Suggest Fly Ash Exposure and Elevated Concentrations of Metal(loid)s

Children who live near coal-fired power plants are exposed to coal fly ash, which is stored in landfills and surface impoundments near residential communities. Fly ash has the potential to be released as fugitive dust. Using data collected from 263 children living within 10 miles of coal ash storage facilities in Jefferson and Bullitt Counties, Kentucky, USA, we quantified the elements found in nail samples. Furthermore, using principal component analysis (PCA), we investigated whether metal(loid)s that are predominately found in fly ash loaded together to indicate potential exposure to fly ash. Concentrations of several neurotoxic metal(loid)s, such as chromium, manganese, and zinc, were higher than concentrations reported in other studies of both healthy and environmentally exposed children. From PCA, it was determined that iron, aluminum, and silicon in fly ash were found to load together in the nails of children living near coal ash storage facilities. These metal(loid)s were also highly correlated with each other. Last, results of geospatial analyses partially validated our hypothesis that children's proximity to power plants was associated with elevated levels of concentrations of fly ash metal(loid)s in nails. Taken together, nail samples may be a powerful tool in detecting exposure to fly ash.

When physical activity meets the physical environment: precision health insights from the intersection

BACKGROUND

The physical environment can facilitate or hinder physical activity. A challenge in promoting physical activity is ensuring that the physical environment is supportive and that these supports are appropriately tailored to the individual or group in question. Ideally, aspects of the environment that impact physical activity would be enhanced, but environmental changes take time, and identifying ways to provide more precision to physical activity recommendations might be helpful for specific individuals or groups. Therefore, moving beyond a "one size fits all" to a precision-based approach is critical.

MAIN BODY

To this end, we considered 4 critical aspects of the physical environment that influence physical activity (walkability, green space, traffic-related air pollution, and heat) and how these aspects could enhance our ability to precisely guide physical activity. Strategies to increase physical activity could include optimizing design of the built environment or mitigating of some of the environmental impediments to activity through personalized or population-wide interventions.

CONCLUSIONS

Although at present non-personalized approaches may be more widespread than those tailored to one person's physical environment, targeting intrinsic personal elements (e.g., medical conditions, sex, age, socioeconomic status) has interesting potential to enhance the likelihood and ability of individuals to participate in physical activity.

Ambient air pollution and the development of overweight and obesity in children: a large longitudinal study

BACKGROUND

Ambient air pollution may play a role in childhood obesity development, but evidence is scarce, and the modifying role of socioeconomic status (SES) is unclear. We aimed to examine the association between exposure to air pollution during early childhood and subsequent risk of developing overweight and obesity, and to evaluate whether SES is a modifier of this association.

METHODS

This longitudinal study included 416,955 children identified as normal weight between 2-5 years old and registered in an electronic primary healthcare record between 2006 and 2016 in Catalonia (Spain). Children were followed-up until they developed overweight or obesity, reached 15 years of age, died, transferred out, or end of study period (31/12/2018). Overweight and obesity were defined following the WHO reference obtained from height and weight measures. We estimated annual residential census levels of nitrogen dioxide (NO₂) and particulate matter <10 μm (PM₁₀), <2.5 μm (PM_2.5), and 2.5-10 μm (PM_coarse) at study entry. We estimated the risk of developing overweight and obesity per interquartile range increase in air pollution exposure with Cox proportional hazard models.

RESULTS

A total of 142,590 (34.2%) children developed overweight or obesity. Increased exposure to NO₂, PM₁₀, and PM_coarse was associated with a 2-3% increased risk of developing overweight and obesity (hazard ratio [HR] per 21.8 μg/m³ NO₂ = 1.03 [95% CI: 1.02-1.04]; HR per 6.4 μg/m³ PM₁₀ = 1.02 [95% CI: 1.02-1.03]; HR per 4.6 µg/m³ PM_coarse = 1.02, [95% CI: 1.01-1.02]). For all air pollutants, associations were stronger among children living in most compared to least deprived areas.

CONCLUSIONS

This study suggests that early life exposure to air pollution may be associated with a small increase in the risk of developing overweight and obesity in childhood, and that this association may be exacerbated in the most deprived areas. Even these small associations are of potential global health importance because air pollution exposure is widespread and the long-term health consequences of childhood obesity are clear.

Objectively measured association between air pollution and physical activity, sedentary behavior in college students in Beijing

The purpose of this study is to examine the association between hourly air pollution on hourly physical activity (PA) and sedentary behavior (SB) among college students in Beijing, China. The secondary aim was to examine such associations varied at specific time. A total of 340 participants were recruited from the Tsinghua University, in Beijing, China. Accelerometers provided PA measures, including moderate-to-vigorous physical activity (MVPA), walking steps, energy expenditure and sedentary time for 7 consecutive days. Corresponding air pollution data by the Beijing Municipal Ecological Environment Bureau in the closed site (Wan Liu site) in Tsinghua University were collected including average hourly air quality index (AQI) and PM_2.5 (μg/m³). Associations were estimated using linear individual fixed-effect regressions. We also conducted an air pollution risk perception survey among 2307 freshmen (76.6% males) who were enrolled in Tsinghua in 2016, and the survey was done in May 22-26, 2017. A one level increase in hourly air quality index (AQI) was associated with a reduction in 1-h PA by 0.083 (95% confidence interval [CI] = -0.137, -0.029) minutes of MVPA, 8.8 (95% CI = -15.0, -2.6) walking steps, 0.65 (95% CI = -1.03, -0.27) kcals of energy expenditure. A 10 μg/m³ increase in air pollution concentration in hourly PM_2.5 was associated with a reduction in 1-h PA by 0.021 (95% confidence interval [CI] = -0.033, -0.010) minutes of MVPA, 2.2 (95% CI = -3.5, -0.9) walking steps, 0.170 (95% CI = -0.250, -0.089) kcals of energy expenditure an increase in 1-h sedentary behavior 0.045 (0.005, 0.0845). At specific time, stronger negative associations of AQI and PM_2.5 air pollution with PA at 8 a.m., 4 p.m., 5 p.m. and 7 p.m. Similarly, stronger positive associations of 1 h AQI and PM_2.5 air pollution with SB at 8 a.m., 9 a.m., 11 a.m., and 7 p.m. A total of 94.9% participants (n = 2235) responded "yes" to air pollution change activities in the survey, which may partially explain PA change. Air pollution may discourage physical activity and increases sedentary behavior among freshman students living in Beijing, China. This is preliminary study. The impact of air pollution on physical activity and sedentary behavior at a specific time may be different.

Air pollution, physical activity and health: A mapping review of the evidence

BACKGROUND

Exposure to air pollution and physical inactivity are both significant risk factors for non-communicable diseases (NCDs). These risk factors are also linked so that the change in exposure in one will impact risks and benefits of the other. These links are well captured in the active transport (walking, cycling) health impact models, in which the increases in active transport leading to increased inhaled dose of air pollution. However, these links are more complex and go beyond the active transport research field. Hence, in this study, we aimed to summarize the empirical evidence on the links between air pollution and physical activity, and their combined effect on individual and population health.

OBJECTIVES AND METHODS

We conducted a non-systematic mapping review of empirical and modelling evidence of the possible links between exposure to air pollution and physical activity published until Autumn 2019. We reviewed empirical evidence for the (i) impact of exposure to air pollution on physical activity behaviour, (ii) exposure to air pollution while engaged in physical activity and (iii) the short-term and (iv) long-term health effects of air pollution exposure on people engaged in physical activity. In addition, we reviewed (v) public health modelling studies that have quantified the combined effect of air pollution and physical activity. These broad research areas were identified through expert discussions, including two public events performed in health-related conferences.

RESULTS AND DISCUSSION

The current literature suggests that air pollution may decrease physical activity levels during high air pollution episodes or may prevent people from engaging in physical activity overall in highly polluted environments. Several studies have estimated fine particulate matter (PM2.5) exposure in active transport environment in Europe and North-America, but the concentration in other regions, places for physical activity and for other air pollutants are poorly understood. Observational epidemiological studies provide some evidence for a possible interaction between air pollution and physical activity for acute health outcomes, while results for long-term effects are mixed with several studies suggesting small diminishing health gains from physical activity due to exposure to air pollution for long-term outcomes. Public health modelling studies have estimated that in most situations benefits of physical activity outweigh the risks of air pollution, at least in the active transport environment. However, overall evidence on all examined links is weak for low- and middle-income countries, for sensitive subpopulations (children, elderly, pregnant women, people with pre-existing conditions), and for indoor air pollution.

CONCLUSIONS

Physical activity and air pollution are linked through multiple mechanisms, and these relations could have important implications for public health, especially in locations with high air pollution concentrations. Overall, this review calls for international collaboration between air pollution and physical activity research fields to strengthen the evidence base on the links between both and on how policy options could potentially reduce risks and maximise health benefits.

Physical activity in an air-polluted environment: behavioral, psychological and neuroimaging protocol for a prospective cohort study (Healthy Aging in Industrial Environment study - Program 4)

BACKGROUND

Air pollution has been linked to increased mortality and morbidity. The Program 4 of the Healthy Aging in Industrial Environment study investigates whether the health and wellbeing benefits of physical activity (PA) can be fully realized in individuals living in highly polluted environments. Herein, we introduce the behavioral, psychological and neuroimaging protocol of the study.

METHODS

This is a prospective cohort study of N = 1500 individuals aged 18-65 years comparing: (1) individuals living in the highly polluted, industrial region surrounding the city of Ostrava (n = 750), and (2) controls from the comparison region with relative low pollution levels in Southern Bohemia (n = 750). Quota sampling is used to obtain samples balanced on age, gender, PA status (60% active runners vs. 40% insufficiently active). Participants are screened and complete baseline assessments through online questionnaires and in-person lab-based assessments of physiological, biomechanical, neuroimaging and cognitive function parameters. Prospective 12-month intensive monitoring of air pollution and behavioral parameters (PA, inactivity, and sleep) follows, with a focus on PA-related injuries and psychological factors through fitness trackers, smartphones, and mobile apps. Subsequently, there will be a 5-year follow-up of the study cohort.

DISCUSSION

The design of the study will allow for (1) the assessment of both short-term variation and long-term change in behavioral parameters, (2) evaluation of the incidence of musculoskeletal injuries and psychological factors impacting behavior and injury recovery, and (3) the impact that air pollution status (and change) has on behavior, psychological resilience, and injury recovery. Furthermore, the integration of MRI techniques and cognitive assessment in combination with data on behavioral, biological and environmental variables will provide an opportunity to examine brain structure and cognitive function in relation to health behavior and air pollution, as well as other factors affecting resilience against and vulnerability to adverse changes in brain structure and cognitive aging. This study will help inform individuals about personal risk factors and decision-makers about the impact of environmental factors on negative health outcomes and potential underlying biological, behavioral and psychological mechanisms. Challenges and opportunities stemming from the timing of the study that coincided with the COVID-19 pandemic are also discussed.

Greenness surrounding schools and adiposity in children and adolescents: Findings from a national population-based study in China

BACKGROUND

Previous studies have indicated that exposure to green space may benefit human health. However, the available evidence concerning the effects of greenness, especially school-based greenness, on pediatric obesity is scarce.

OBJECTIVE

To explore the association between school-based greenness and adiposity in children and adolescents in China.

METHOD

We conducted a nationwide cross-sectional study of 56,620 children and adolescents (aged 6-18 years) in seven provinces/municipalities across China. School-based greenness was assessed using satellite-derived Normalized Difference Vegetation Index (NDVI) and Soil Adjusted Vegetation Index (SAVI) within 100-, 500-, and 1000-m circular buffers around each school's address. Generalized linear mixed regression models were used to estimate associations of greenness with BMI z-scores (zBMI), waist circumference, and prevalent overweight/obesity. We also explored the potential mediating role of ambient air pollution and physical activity in the greenness-adiposity associations.

RESULT

In the adjusted model, an IQR increase in NDVI_-1000m was associated with lower zBMI (β: -0.11, 95% confidence interval[CI]: -0.13,-0.09) and waist circumference (β: -0.64, 95%CI: -0.78,-0.50). Consistently, an IQR increase in NDVI_-100m, NDVI_-500m, NDVI_-1000m was associated with 7-20% lower odds of overweight/obesity in the adjusted models. Air pollutants mediated 6.5-29.1% of the association between greenness and zBMI. No significant mediation effect was observed for physical activity.

CONCLUSION

Higher school-based greenness levels were associated with lower zBMI, waist circumference, and lower odds of overweight and obesity in children and adolescents. Ambient air pollutants may partially mediate the greenness-adiposity associations.

Relationship between inter-city air pollution levels and physical fitness parameters among sixth-grade Mongolian primary school boys, China, 2013–2016

Objectives

Adverse health effects due to air pollution have recently been recognized as a serious social problem in China. In this study, we investigated inter-city relationships between air pollution and physical fitness levels among Mongolian elementary school boys in five cities of the Inner Mongolia Autonomous Region (IMAR), China.

Study design

Retrospective cross-sectional cohort study.

Methods

Physical fitness measurements of 1443 male Mongolian sixth-grade children were obtained from an existing dataset from the year 2013–2016, and correlations were calculated between these measurements and the percentage of good air quality days for five different cities: Hohhot, Baotou, Chifeng, Bayannur, and Xilinhot.

Results

Significant differences in the percentage of good air quality days from 2013 to 2016 were observed among the five cities studied. Statistical analysis showed a significantly positive correlation between good days and students’ vital capacity, and a significantly negative correlation between good days and 50 ​m ​× ​8 shuttle run time for the students included in this study. Differences in the extent of air pollution among the study cities might account for differences in lung function and cardiovascular endurance levels in these Mongolian children.

Conclusions

There is an urgent need for policy intervention to reduce air pollution levels in the IMAR. It is necessary to improve school physical education classes and physical training considering the current air pollution situation. Future research needs to replicate school year survey results from other cities, include longitudinal studies, and clarify the relationship between air pollution, physical exercise, and overall health.

•

Inter-city relationship between air pollution and physical fitness.

•

Policy intervention to reduce air pollution in the Inner Mongolia Autonomous Region.

•

Need to improve school physical education training due to current air pollution.

Trace metals contamination in groundwater and implications on human health: comprehensive assessment using hydrogeochemical and geostatistical methods

Monitoring the groundwater chemical composition and identifying the presence of pollutants is an integral part of any comprehensive groundwater management strategy. The present study was conducted in a part of West Tripura, northeast India, to investigate the presence and sources of trace metals in groundwater and the risk to human health due to direct ingestion of groundwater. Samples were collected from 68 locations twice a year from 2016 to 2018. Mixed Ca-Mg-HCO3, Ca-Cl and Ca-Mg-Cl were the main groundwater types. Hydrogeochemical methods showed groundwater mineralization due to (1) carbonate dissolution, (2) silicate weathering, (3) cation exchange processes and (4) anthropogenic sources. Occurrence of faecal coliforms increased in groundwater after monsoons. Nitrate and microbial contamination from wastewater infiltration were apparent. Iron, manganese, lead, cadmium and arsenic were above the drinking water limits prescribed by the Bureau of Indian Standards. Water quality index indicated 1.5% had poor, 8.7% had marginal, 16.2% had fair, 66.2% had good and 7.4% had excellent water quality. Correlation and principal component analysis reiterated the sources of major ions and trace metals identified from hydrogeochemical methods. Human exposure assessment suggests health risk due to high iron in groundwater. The presence of unsafe levels of trace metals in groundwater requires proper treatment measures before domestic use.

Windows of opportunity for daily physical activity

Air pollution is a serious concern to people who want to engage in physical activities to improve and maintain their health. However, air quality data collected at the nearest monitoring site may not be the best source of information because the data may be incomplete (e.g., some pollutants are not monitored) or not representative. This paper puts forward a method that uses air quality data from a large area to derive a diurnal profile of air quality variation for that area and identify the time window in which the air quality is typically the best during a day. If people exercise in that time window then they can minimize their exposure to air pollution. Three years’ worth of air quality data in five California counties were analyzed to identify the general pattern of diurnal variation of air quality. The analysis shows the pattern of air quality variation is very similar among those five counties which represent diverse geographical and meteorological conditions. The analysis further reveals that in California air quality is generally the best in early mornings; as such, people should exercise in the early morning if their daily schedule allows it. A similar analysis can be performed for other areas to help people choose the best time window to exercise.

Assessment of Accelerometer-Based Physical Activity During the 2017-2018 California Wildfire Seasons

This cohort study investigates the accelerometer-based physical activity in Californians residing within 10 miles of a monitoring station that registered at least 1 day with an air quality index score greater than 200 during the 2017 to 2018 wildfire seasons.

Pollution, Health, and the Moderating Role of Physical Activity Opportunities

Air and water pollution have detrimental effects on health, while physical activity opportunities have a positive relationship. The purpose of this study was to explore whether physical activity opportunities moderate the relationships among air and water pollution, and measures of health. Aggregate data were collected at the county level in the United States (n = 3104). Variables included the mean daily density of fine particle matter (air pollution), reported cases of health-related drinking water violations (water pollution), subjective ratings of poor or fair health (overall health), the number of physically and mentally unhealthy (physical and mental health, respectively), and the percentage of people living in close proximity to a park or recreation facility (access to physical activity). Air and water pollution have a significant positive effect on all measures of residents’ poor health, while physical activity opportunities only have a negative effect on overall health and physical health. Access to physical activity only moderates the relationship between air pollution and all health outcomes. Since physical activity behavior can be more rapidly changed than some causes of pollution, providing the resident population with better access to physical activity can represent an effective tool in environmental health policy.

Associations between perceived environmental pollution and health-related quality of life in a Chinese adult population

BACKGROUND

Health-related quality of life (HRQoL) measures are being used in increasingly diverse populations. However, there have no known studies to date to examine the associations between perceived environmental pollution and HRQoL in a Chinese population. This study aimed to report the associations between air, water, noise pollution and HRQoL among Chinese adult population.

METHODS

A cross-sectional survey data was used from East Asian Social Survey 2010 with a sample of 3866 Chinese populations regarding environmental pollution. HRQoL was computed by SF-12 and reflected by physical and mental component summary score (PCS & MCS). Ordinary least regression analyses were used to examine associations between perceived environmental pollution and PCS and MCS scores. Models in SPSS PROCESS were selected to demonstrate the moderating and mediating effects.

RESULTS

Only considering one pollutant, perceived air pollution and perceived water pollution had significant associations with PCS and MCS scores. Perceived noise pollution had significant associations with PCS scores. Perceived air×noise, air×water, noise×water, and air×noise×water pollution had significant associations with PCS and MCS scores. Conditional (moderated) mediation showed that there were no moderating effects and mediating effects of perceived one pollutant on another pollutant.

CONCLUSIONS

Co-occurring perceived environmental pollution were mainly associated with progressive increase in PCS and MCS scores among the Chinese adult population. These results suggested that some effective policies should be carried out to improve environmental quality in Chinese adult population.

The association between long-term exposure to low-level PM2.5 and mortality in the state of Queensland, Australia: A modelling study with the difference-in-differences approach

BACKGROUND

To date, few studies have investigated the causal relationship between mortality and long-term exposure to a low level of fine particulate matter (PM2.5) concentrations.

METHODS AND FINDINGS

We studied 242,320 registered deaths in Queensland between January 1, 1998, and December 31, 2013, with satellite-retrieved annual average PM2.5 concentrations to each postcode. A variant of difference-in-differences (DID) approach was used to investigate the association of long-term PM2.5 exposure with total mortality and cause-specific (cardiovascular, respiratory, and non-accidental) mortality. We observed 217,510 non-accidental deaths, 133,661 cardiovascular deaths, and 30,748 respiratory deaths in Queensland during the study period. The annual average PM2.5 concentrations ranged from 1.6 to 9.0 μg/m3, which were well below the current World Health Organization (WHO) annual standard (10 μg/m3). Long-term exposure to PM2.5 was associated with increased total mortality and cause-specific mortality. For each 1 μg/m3 increase in annual PM2.5, we found a 2.02% (95% CI 1.41%-2.63%; p < 0.01) increase in total mortality. Higher effect estimates were observed in Brisbane than those in Queensland for all types of mortality. A major limitation of our study is that the DID design is under the assumption that no predictors other than seasonal temperature exhibit different spatial-temporal variations in relation to PM2.5 exposure. However, if this assumption is violated (e.g., socioeconomic status [SES] and outdoor physical activities), the DID design is still subject to confounding.

CONCLUSIONS

Long-term exposure to PM2.5 was associated with total, non-accidental, cardiovascular, and respiratory mortality in Queensland, Australia, where PM2.5 levels were measured well below the WHO air quality standard.

Personal strategies to minimise effects of air pollution on respiratory health: advice for providers, patients and the public

As global awareness of air pollution rises, so does the imperative to provide evidence-based recommendations for strategies to mitigate its impact. While public policy has a central role in reducing air pollution, exposure can also be reduced by personal choices. Qualified evidence supports limiting physical exertion outdoors on high air pollution days and near air pollution sources, reducing near-roadway exposure while commuting, utilising air quality alert systems to plan activities, and wearing facemasks in prescribed circumstances. Other strategies include avoiding cooking with solid fuels, ventilating and isolating cooking areas, and using portable air cleaners fitted with high-efficiency particulate air filters. We detail recommendations to assist providers and public health officials when advising patients and the public regarding personal-level strategies to mitigate risk imposed by air pollution, while recognising that well-designed prospective studies are urgently needed to better establish and validate interventions that benefit respiratory health in this context.

Leisure-Time Physical Inactivity’s Association With Environmental, Demographic, and Lifestyle Factors in the United States

Background: This study examined the effects of environmental, demographic, and lifestyle factors on leisure-time physical inactivity (LTPI). Methods: Analyses were based on county-level data in the contiguous United States. Statistical methods included simple regression, univariate, and multivariate 2-level organizational models (mixed models), and the intraclass correlation coefficient. Results: Higher average daily maximum air temperature was directly and indirectly (through smoking and obesity) positively associated with LTPI. Higher average fine particulate matter was positively associated with LTPI. Higher precipitation was negatively associated with LTPI. Altitude (≥1500 m) was associated with lower LTPI, directly because of better physical health at higher altitude and indirectly through temperature, fine particulate matter, precipitation, poverty, smoking, and obesity. Urban dwelling had direct and indirect (through poverty) negative associations with LTPI. Poverty had direct and indirect (through smoking and obesity) associations with LTPI. Smoking, poverty, and black race were each positively associated with LTPI. The association between black race and LTPI was explained by poverty. Modifying influences of gender, precipitation, and altitude were identified. Conclusions: The significant effects of temperature, fine particulate matter, precipitation, altitude, urban dwelling, poverty, smoking, and obesity on LTPI were both direct and indirect, and sex, precipitation, and altitude modified many of these associations.

Residential greenness, air pollution and psychological well-being among urban residents in Guangzhou, China

China's rapid urbanization has led to an increasing level of exposure to air pollution and a decreasing level of exposure to vegetation among urban populations. Both trends may pose threats to psychological well-being. Previous studies on the interrelationships among greenness, air pollution and psychological well-being rely on exposure measures from remote sensing data, which may fail to accurately capture how people perceive vegetation on the ground. To address this research gap, this study aimed to explore relationships among neighbourhood greenness, air pollution exposure and psychological well-being, using survey data on 1029 adults residing in 35 neighbourhoods in Guangzhou, China. We used the Normalized Difference Vegetation Index (NDVI) and streetscape greenery (SVG) to assess greenery exposure at the neighbourhood level, and we distinguished between trees (SVG-tree) and grasses (SVG-grass) when generating streetscape greenery exposure metrics. We used two objective (PM_2.5 and NO₂ concentrations) measures and one subjective (perceived air pollution) measure to quantify air pollution exposure. We quantified psychological well-being using the World Health Organization Well-Being Index (WHO-5). Results from multilevel structural equation models (SEM) showed that, for parallel mediation models, while the association between SVG-grass and psychological well-being was completely mediated by perceived air pollution and NO₂, the relationship between SVG-tree and psychological well-being was completely mediated by ambient PM_2.5, NO₂ and perceived air pollution. None of three air pollution indicators mediated the association between psychological well-being and NDVI. For serial mediation models, measures of air pollution did not mediate the relationship between NDVI and psychological well-being. While the linkage between SVG-grass and psychological well-being scores was partially mediated by NO₂-perceived air pollution, SVG-tree was partially mediated by both ambient PM_2.5-perceived air pollution and NO₂-perceived air pollution. Our results suggest that street trees may be more related to lower air pollution levels and better mental health than grasses are.

Short-term Effect of Air Pollution on Tuberculosis Based on Kriged Data: A Time-series Analysis

Tuberculosis (TB) has a very high mortality rate worldwide. However, only a few studies have examined the associations between short-term exposure to air pollution and TB incidence. Our objectives were to estimate associations between short-term exposure to air pollutants and TB incidence in Wuhan city, China, during the 2015–2016 period. We applied a generalized additive model to access the short-term association of air pollution with TB. Daily exposure to each air pollutant in Wuhan was determined using ordinary kriging. The air pollutants included in the analysis were particulate matter (PM) with an aerodynamic diameter less than or equal to 2.5 micrometers (PM_2.5), PM with an aerodynamic diameter less than or equal to 10 micrometers (PM₁₀), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), carbon monoxide (CO), and ground-level ozone (O₃). Daily incident cases of TB were obtained from the Hubei Provincial Center for Disease Control and Prevention (Hubei CDC). Both single- and multiple-pollutant models were used to examine the associations between air pollution and TB. Seasonal variation was assessed by splitting the all-year data into warm (May–October) and cold (November–April) seasons. In the single-pollutant model, for a 10 μg/m³ increase in PM_2.5, PM₁₀, and O₃ at lag 7, the associated TB risk increased by 17.03% (95% CI: 6.39, 28.74), 11.08% (95% CI: 6.39, 28.74), and 16.15% (95% CI: 1.88, 32.42), respectively. In the multi-pollutant model, the effect of PM_2.5 on TB remained statistically significant, while the effects of other pollutants were attenuated. The seasonal analysis showed that there was not much difference regarding the impact of air pollution on TB between the warm season and the cold season. Our study reveals that the mechanism linking air pollution and TB is still complex. Further research is warranted to explore the interaction of air pollution and TB.

Long-term exposure to PM2.5 and fasting plasma glucose in non-diabetic adolescents in Yogyakarta, Indonesia

BACKGROUND

Indonesia is facing serious air pollution. However, very few studies have been conducted to examine the health risks of air pollution in Indonesia, particularly for adolescents.

OBJECTIVE

To assess the association between long-term exposure to ambient particles with a diameter of <2.5 μm (PM_2.5) and fasting plasma glucose (FPG) in adolescents.

METHODS

A cross-sectional study was conducted in 482 adolescents aged 14-18 years in Yogyakarta, Indonesia in 2016. We finally included 469 (97.30%) participants who had no missing data for data analysis. We collected individual data on socio-demographics, behavioral habits, and health information through standardized questionnaires. Satellite-based PM_2.5 concentrations from 2013 to 2016 were assigned based on participants' residential addresses. The association between PM_2.5 and FPG was examined using a generalized linear regression model while FPG was modeled as a continuous variable. An ordered logistic regression model was used to assess the relationship between PM_2.5 and FPG categories.

RESULTS

Every 1 μg/m³ increase in PM_2.5 was associated with a 0.34 mg/dL [95 confidence interval (95% CI): 0.08 mg/dL, 0.59 mg/dL] increase in FPG levels. Comparing with the low FPG level (under 86 mg/dL), every 1 μg/m³ increase in PM_2.5 was associated with a 10.20% (95% CI: 1.60%, 19.80%) increase in the odds of impaired fasting glucose (IFG) (100-125 mg/dL). Stratified analyses indicated greater effects on participants with hypertension [odds ratio (OR) = 1.30, 95% CI: 1.09, 1.57] and those had higher physical activities (OR = 1.36, 95% CI: 1.09, 1.57). Adolescents' sex, obesity status and different cutoff points of FPG did not modify the association between the exposure to PM_2.5 and FPG levels.

CONCLUSION

Long-term exposure to PM_2.5 was associated with increased FPG levels in Indonesian non-diabetic adolescents.