Increase In Air Pollution Concentration Research Articles

Short-term effects of air pollution on hospitalization for acute lower respiratory infections in children: a time-series analysis study from Lanzhou, China

BackgroundShort-term exposure to air pollution is associated with acute lower respiratory infections (ALRI) in children. We investigated the relationship between hospitalization for ALRI in children and air pollutant concentrations from January 1, 2014 to December 31, 2020 in Lanzhou City.MethodsWe collected data on air pollutant concentrations and children’s hospitalization data during the study period. A time series regression analysis was used to assess the short-term effects of air pollutants on ALRI in children, and subgroup analyses and sensitivity analyses were performed.ResultsA total of 51,206 children with ALRI were studied, including 40,126 cases of pneumonia and 11,080 cases of bronchiolitis. The results of the study revealed that PM2.5, PM10, SO2 and NO2 were significantly associated with hospitalization for ALRI in children aged 0–14 years. For each 10 µg/m3 increase in air pollutant concentration in lag0-7, the relative risk of ALRI hospitalization in children due to PM2.5, PM10, SO2 and NO2 increased by 1.089 (95%CI:1.075, 1.103), 1.018 (95%CI:1.014, 1.021), 1.186 (95%CI:1.154. 1.219) and 1.149 (95%CI:1.130, 1.168), respectively.ConclusionsPM2.5, PM10, SO2 and NO2 short-term exposures were positively associated with ALRI, pneumonia and bronchiolitis hospitalizations in Lanzhou, China. Local governments should make efforts to improve urban ambient air quality conditions to reduce hospitalization rates for childhood respiratory diseases.

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

BackgroundExposure 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.MethodsPA 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), PM2.5 (µg/m³), and PM10 (µg/m³). Associations were estimated using linear individual fixed-effect regressions.ResultsA 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 PM2.5 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.ConclusionAir 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.

A systematic review and meta-analysis of air pollution and angina pectoris attacks: identification of hazardous pollutant, short-term effect, and vulnerable population.

We conducted a systematic review and meta-analysis of global epidemiological studies of air pollution and angina pectoris, aiming to explore the deleterious air pollutant(s) and vulnerable sub-populations. PubMed and Web of Science databases were searched for eligible articles published between database inception and October 2021. Meta-analysis weighted by inverse-variance was utilized to pool effect estimates based on the type of air pollutant, including particulate matters (PM2.5 and PM10: particulate matter with an aerodynamic diameter ≤ 2.5µm and ≤ 10µm), gaseous pollutants (NO2: nitrogen dioxide; CO: carbon monoxide; SO2: sulfur dioxide, and O3: ozone). Study-specific effect estimates were standardized and calculated with percentage change of angina pectoris for each 10µg/m3 increase in air pollutant concentration. Twelve studies involving 663,276 angina events from Asia, America, Oceania, and Europe were finally included. Meta-analysis showed that each 10µg/m3 increase in PM2.5 and PM10 concentration was associated with an increase of 0.66% (95%CI: 0.58%, 0.73%; p < 0.001) and 0.57% (95%CI: 0.20%, 0.94%; p = 0.003) in the risk of angina pectoris on the second day of exposure. Adverse effects were also observed for NO2 (0.67%, 95%CI: 0.33%, 1.02%; p < v0.001) on the second day, CO (0.010%, 95%CI: 0.006%, 0.014%; p < 0.001). The elderly and patients with coronary artery disease (CAD) appeared to be at higher risk of angina pectoris. Our findings suggest that short-term exposure to PM2.5, PM10, NO2, and CO was associated with an increased risk of angina pectoris, which may have implications for cardiologists and patients to prevent negative cardiovascular outcomes.

Associations between ambient air pollutants and clonal hematopoiesis of indeterminate potential (CHIP)

BACKGROUND AND AIM: Biological mechanisms underlying the relationship between exposure to ambient air pollution and development of cardiovascular disease (CVD) have not been adequately described. One pathway could involve acquisition of somatic mutations associated with incidence of hematologic cancers and CVD termed “clonal hematopoiesis of indeterminate potential” (CHIP), most commonly mutated in DNMT3A. We assessed cross-sectional associations between long-term air pollutant concentrations and CHIP mutation prevalence. METHODS: CHIP mutations were identified in the Trans-omics for Precision Medicine program using blood DNA-derived whole genome sequencing for participants of the Multi-Ethnic Study of Atherosclerosis. A spatio-temporal modeling framework predicted individual-level average air pollution concentrations (particulate matter 2.5 µm, PM2.5; nitrogen dioxide, NO2; oxides of nitrogen, NOx) at residential locations one year before blood draw (Exams 1-3, 2000-2005). Primary exclusions were history of hematologic malignancy or myelosuppressive chemotherapeutics. Logistic regression estimated odds ratios (OR) of CHIP mutation per IQR increase in air pollutant concentration, adjusting for age, gender, smoking status, race/ethnicity, income, and calendar year. RESULTS:4,445 individuals were included and 196 (4.41%) had CHIP mutations. 67.9% of CHIP mutations were in DNMT3A. Adjusted ORs for CHIP per increase in air pollution were increased, however did not reach statistical significance. ORs for CHIP mutation were 1.05 (95% CI 0.90, 1.23) per 4 µg/m3 for PM2.5, 1.18 (95% CI 0.87, 1.59) per 16 ppb for NO2, and 1.21 (95% CI 0.93, 1.56) per 38 ppb for NOx. Adjusted ORs for DNMT3A-specific CHIP were 1.13 (95% CI 0.94, 1.36) for PM2.5, 1.26 (95% CI 0.87, 1.81) for NO2, and 1.28 (95% CI 0.93, 1.75) for NOx. CONCLUSIONS:Our results are suggestive of associations between long term concentrations in air pollution and prevalence of CHIP mutations, but not statistically significant. A larger sample size may be required to provide insight into the relationship between air pollution and CHIP. KEYWORDS: air pollution, pm2.5, no2, CHIP

Hourly air pollution exposure and emergency department visit for acute myocardial infarction: Vulnerable populations and susceptible time window

Although short-term exposure to air pollution can trigger sudden heart attacks, evidence is scarce regarding the relationship between sub-daily changes in air pollution level and the risk of acute myocardial infarction (AMI). Here we assessed the intraday effect of air pollution on AMI risk and potential effect modification by pre-existing cardiac risk factors. Hourly data on emergency department visits (EDVs) for AMI and air pollutants in Brisbane, Australia during 2013–2015 were acquired from pertinent government departments. A time-stratified case-crossover analysis was adopted to examine relationships of AMI risk with hourly changes in particulate matters (aerodynamic diameter ≤ 2.5 μm (PM2.5) and ≤10 μm (PM10)) and gaseous pollutants (ozone and nitrogen dioxide) after adjusting for potential confounders. We also conducted stratified analyses according to age, gender, disease history, season, and day/night time exposure. Excess risk of AMI per 10 μg/m3 increase in air pollutant concentration was reported at four time windows: within 1, 2–6, 7–12, and 13–24 h. Both single- and multi-pollutant models found an elevated risk of AMI within 2–6 h after exposure to PM2.5 (excessive risk: 12.34%, 95% confidence interval (CI): 1.44%–24.42% in single-pollutant model) and PM10 within 1 h (excessive risk: 5.21%, 95% CI: 0.26%–10.40% in single-pollutant model). We did not find modification effect by age, gender, season or day/night time, except that PM2.5 had a greater effect on EDVs for AMI during night-time than daytime. Our findings suggest that AMI risk could increase within hours after exposure to particulate matters.

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 PM2.5 (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 PM2.5 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 PM2.5 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 PM2.5 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.

Short term association between air pollution (PM10, NO2 and O3) and secondary spontaneous pneumothorax

Secondary spontaneous pneumothorax (SSP) occurs in the context of underlying pulmonary disease. Our objectives were to estimate the relationship between SSP and short term air pollution exposure with nitrogen dioxide (NO2), ozone (O3) and particulate matter with a diameter ≤ 10 μm (PM10). Patients with SSP were included between June 1, 2009 and May 31, 2013, in 14 Emergency Departments in France. In this case–crossover design study, PM10, NO2, and O3 data were collected hourly from monitoring stations. Quantitative values, fast increase in air pollutant concentration, and air quality threshold exceedance were retained. These assessments were calculated for each of the 4 days prior to the event (Lag 1–Lag 4) for all case and control period, and for the entire exposure period. A total of 135 patients with SSP were included, with a mean age of 55.56 (SD 18.54) years. For short term exposure of PM10, NO2 and O3, no differences were observed between case and control periods in terms of quantitative values of air pollutant exposure (P > 0.68), fast increase in concentration (P > 0.12) or air quality threshold exceedance (P > 0.68). An association between O3 exposures cannot be ruled out, especially when considering the Lag 2 prior to the event and in warm seasons.

Does air pollution aggravate income inequality in China? An empirical analysis based on the view of health

Given the rapid development of the Chinese economy, especially its accelerated urbanization, air pollution and income inequality, as two of the most important global issues, have also become hot topics in China. However, limited attention has been devoted to understanding their joint evolution in the literature. In this study, we thus investigate the relationship between them using a multi-level nested data model, which enables us to estimate the long-run distribution effect of air pollution on individuals of different socioeconomic statuses, based on China’s city-level PM2.5 emissions and individual-level income. We further examine the mechanisms behind the evolution using a 3SLS model. The estimation results reveal that the increase in air pollution concentration has short-term positive production effects and long-term negative impacts on individual income, and will exacerbate the income inequality across socioeconomic statuses. Individuals of lower socioeconomic status have disadvantages in achieving efficient avoiding knowledge and measures. The results of 3SLS model confirm the existence of the health channel through which air pollution exerts influence on income inequality. These results provide a roadmap for policymakers. First, a comprehensive assessment of the health burden distribution from air pollution on individuals of different socioeconomic statuses should be considered for environmental policymaking. Second, the regional disparities and differences among income groups should also be considered during this process. Third, equal access to basic public services should be the primary target of environmental regulations. Moreover, compensation and assistance for the health issues caused by environmental pollution could be an important supplement to these regulations. Future study could do further analysis of the specific level of health burden due to different types of pollutants and their relationship with income inequality.

Objectively Measured Association Between Air Pollution And Physical Activity In College Students In Beijing

PURPOSE: To examine the association between hourly air pollution on hourly physical activity (PA) among college students in Beijing, China. METHODS: A total of 340 participants (70.58% male) were recruited from the Tsinghua University, in Beijing, China. Accelerometers provided PA measures, including moderate-to-vigorous physical activity (MVPA), walking steps, energy expenditure 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 PM2.5 (μg/m3). Associations were estimated using linear individual fixed-effect regressions. RESULTS: A one level increase in hourly air quality index (AQI) was associated with an reduction in one-hour PA by 0.083 (95% confidence interval [CI] =-0.137, -0.029) minutes of MVPA, 8.822 (95% CI = -15.028, -2.617) walking steps, 0.653 (95% CI =-1.033, -0.273) kcals of energy expenditure. A 10μg/m3 increase in air pollution concentration in hourly PM2.5 was associated with a reduction in one-hour PA by 0.021 (95% confidence interval [CI] =-0.033, -0.010) minutes of MVPA, 2.232 (95% CI = -3.548, -0.916) walking steps, 0.170 (95% CI =-0.250, -0.089) kcals of energy expenditure. CONCLUSIONS: Although there is a negative trend between air pollution and PA, their impact on college students in Beijing seems limited.

Association Between Air Pollution And Daytime Sleep Duration: A Follow-up Study Of Chinese Older Adults In Beijing

PURPOSE: This study was to estimate the association between air pollution and daytime sleep duration for older adults from the 5-year follow-up Chinese older adult surveys during 2011-2016 in Beijing, China. METHODS: We conducted follow-up health surveys on 5503 (2080 males & 3423 females; Age 67.6 ± 8.2 yr., Height = 162.2 ± 7.5 cm, Weight = 63.3±9.8 kg, BMI = 24.1 ± 43.2 in 2011) older adults enrolled at Beijing from 2011 to 2016, once per year. Sleep duration was measured using the Pittsburgh Sleep Quality Index (CPSQI), which has been validated in China to measure sleep duration. Corresponding levels of average hourly PM2.5 (μg/m3) on the survey days were gathered from data provided by the mission China air quality monitoring program run by the US Department of State in Beijing. The data were analyzed using the linear individual fixed-effect regressions. RESULTS: The average time spent in daytime sleep for older adults was 0.6 ± 0.5 hours/day. The mean PM2.5 was 123.9 ± 52.5 (μg/m3). Daytime sleep was positively associated with air pollution for older adults. Overall, an one standard deviation (SD) increase in air pollution concentration in PM2.5 (56.6μg/m3 ) was associated with an increase in daytime sleep hours by 1.49 (95% confidence interval [CI] = 1.17, 1.81), with the corresponding increases in females and males were 0.91 (95% [CI] = 0.33, 1.49) and 1.82 (95% [CI] = 1.34, 2.30) hours, respectively. CONCLUSIONS: Increased air pollution seems led more daytime sleep among older Chinese adults and the impact on males was more significant than females.

Associations of ambient air pollutant exposure with seminal plasma MDA, sperm mtDNA copy number, and mtDNA integrity

BackgroundCurrent available evidence regarding the detrimental effects of low-level ambient air pollution on conventional semen parameters is inconclusive. In nonreproductive systems, air pollutant exposure has been demonstrated to induce oxidative stress (OS), which is a crucial mechanism that mediates sperm damage and male infertility. Thus, it may be essential to investigate the effects of air pollution on sperm quality in terms of the perspectives of OS and relative molecular damage. ObjectivesWe assessed the associations of major air pollutant exposure to oxidative stress-mediated alterations in semen, including seminal plasma malondialdehyde (MDA), sperm mtDNA copy number, and integrity. MethodsThe present study used data gathered from 516 young men participating in the Male Reproductive Health in Chongqing College student (MARCHS) cohort study during the follow-up stage in 2014 (n = 427 on the old campus, which is located in an urban area and has worse air quality, and n = 89 on the new campus, which is not urban and has better air quality). Data regarding major air pollutant exposure during 0–90, 0–9, 10–14 and 70–90 days before each semen examination (corresponding to the entire and three key periods of sperm development, respectively) were collected. The Mann-Whitney U nonparametric test was employed to compare distributions of major air pollutants and to explore differences in MDA, mtDNA copy number, and mtDNA integrity between the two campuses. A linear regression model was used as multivariable analysis to investigate associations of major air pollutant exposure with these biomarkers of oxidative damage to sperm and to adjust for potential confounders. ResultsDuring all four key periods of sperm development, compared with college students on the new campus, college students on the old campus were exposed to higher levels of PM10, PM2.5, NO2, and CO, and had higher air quality index (AQI) values, indicating that these participants suffered from worse air quality. The levels of seminal plasma MDA in college students on the old campus were higher than those for the new campus (2.0 nmol/ml; 0.7, 3.6 vs. 1.6 nmol/ml; 0.4, 3.4, p < 0.001) (medians with 5th and 95th percentiles). There were no significant differences in sperm mtDNA copy number and mtDNA integrity between the two campuses. Furthermore, daily average PM10 exposure during 0–90 days before semen ejaculation was found to be significantly and positively associated with seminal plasma MDA level (10.4; 95% CI, 4.4, 16.4) (percentage change per 10-unit increase in air pollutant concentration; same meanings for the results below); daily average SO2 exposure for 70–90 days and NO2 exposure for 0–9 days prior to sampling were also positively associated with MDA level (74.7; 95% CI, 32.1, 119 and 11.9; 95% CI, 4.8, 19.0, respectively). AQI for 0–90 days and 70–90 days prior to sampling positively correlated with seminal plasma MDA concentrations (11.4; 95% CI, 4.7, 18.1 and 12.2; 95% CI, 5.3, 19.1, respectively). Additionally, daily average SO2 exposures for 10–14 and 0–9 days prior to sampling were negatively associated with sperm mtDNA copy number and mtDNA integrity, respectively (−9.0; 95% CI, −16.4, −1.6 and −38.3; 95% CI, −64.1, −11.8, respectively). However, only the correlations between SO2 exposure and AQI value for 70–90 days prior to sampling and MDA levels remained significant after multiplicity adjustment. ConclusionsThe results indicate that bad air quality, especially SO2 exposure during certain periods of sperm development, might be correlated with oxidative damage to sperm. These findings can deepen the understanding of the potential impacts of air pollution on sperm quality.

Association between exposure to traffic-related air pollution and pediatric allergic diseases based on modeled air pollution concentrations and traffic measures in Seoul, Korea: a comparative analysis

BackgroundPediatric allergic diseases are a major public health concern, and previous studies have suggested that exposure to traffic-related air pollution (TRAP) exposure is a risk factor. These studies have typically assessed TRAP exposure using traffic measures, such as distance to major roads, or by modeling air pollutant concentrations; however inconsistent associations with pediatric allergic diseases have often been found. Using road proximity and density, we previously found an association between TRAP and atopic eczema among approximately 15,000 children living in Seoul, Korea, heavily populated and highly polluted city in which traffic is a major emission source. We aimed to conduct a parallel analysis using modeled air pollution concentrations and thus examine the consistency of the association. Specifically, we examined the associations of individual-level annual-average concentrations of NO2, PM10, and PM2.5 with symptoms and diagnoses of three pediatric allergic diseases including asthma, allergic rhinitis, and atopic eczema.MethodsThe study population included 14,614 children from the Seoul Atopy Friendly School Project Survey in Seoul, Korea, in 2010. To assess individual exposures to TRAP among these children, we predicted annual-average concentrations of NO2, PM10, and PM2.5 at the children’s home addresses in 2010 using universal kriging and land use regression models along with regulatory air quality monitoring data and geographic characteristics. Then, we estimated odds ratios (ORs) of the three allergic diseases for interquartile increases in air pollution concentrations after adjusting for individual risk factors in mixed effects logistic regression.ResultsSymptoms and diagnoses of atopic eczema symptoms showed an association with NO2 (OR = 1.07, 95% confidence interval = 1.02–1.13; 1.08, 1.03–1.14) and PM10 (1.06, 1.01–1.12; 1.07, 1.01–1.13). ORs of PM2.5 were positive but not statistically significant (1.01, 0.95–1.07; 1.04, 0.98–1.10). No association was found between asthma and allergic rhinitis, although PM2.5 showed a marginal association with allergic rhinitis.ConclusionsOur consistent findings regarding the association between TRAP and the prevalence of atopic eczema using traffic measures and surrogate air pollutants suggested the effect of TRAP on children’s health. Follow-up studies should elucidate the causal link, to support subsequent policy considerations and minimize adverse health effects in children.

Climate-Conscious Urban Growth Mitigates Urban Warming: Evidence from Shenzhen, China.

Urban growth comes with significant warming impacts and related increases in air pollution concentrations, so many cities have implemented growth management to minimize "sprawl" and its environmental consequences. However, controlling the amount of growth is costly. Therefore, in this Article, we focus on urban warming and investigate whether climate-conscious urban growth planning (CUGP), that is, urban growth with the same magnitude but optimized spatial arrangements, brings significant mitigation effects. First, the classical spatial multiobjective land-use optimization (SMOLA) model is improved by integrating the spatially, diurnally, and compositionally varying associations between land-use and their warming impacts. We then solve the improved model using the nondominated genetic algorithm (NSGA-II) to generate urban growth plans with minimal warming impacts and minimal cost of change without reducing the amount of urban growth. Results show that climate-conscious urban growth brings 33.3 ± 4.6% less warming impacts as compared to unplanned urban growth in Shenzhen, China, and suggest a compact and spatially equalized development pattern. This study provides evidence that spatial planning tools such as the CUGP can help mitigate human impacts on the environment. Meanwhile, the improved SMOLA model could be applied to balance urban development and other environmental consequences such as air pollution.

The Association between Air Pollution and Sleep Duration: A Cohort Study of Freshmen at a University in Beijing, China.

Background: Rising levels of air pollution in Beijing, China have become a serious environmental issue affecting human health, and young adults are experiencing high rates of insufficient sleep duration or a lack of sleep. Gaps in previous research remain regarding the relationship between air pollution and sleep duration among young adults. The purpose of this study is to assess the associations between air pollution and sleep duration among college students living in Beijing, China. Methods: We conducted follow-up health surveys on 16,889 freshman students enrolled at Tsinghua University over a five-year study period (2013–2018). Sleep duration was measured using the Chinese version of the Pittsburgh Sleep Quality Index (CPSQI), which has been validated in China to measure sleep duration. Corresponding levels of the average hourly air quality index (AQI), PM2.5 (µg/m3), PM10 (µg/m3), and NO2 (µg/m3) were gathered from data provided by the Beijing Municipal Ecological Environment Bureau in a closed site at Tsinghua University. Multilevel mixed-effects linear regression models were used to analyze the data. Results: One standard deviation increase in air pollution concentration in AQI, PM2.5, PM10, and NO2 was associated with a reduction in daily hours of sleep by 0.68 (95% confidence interval (CI) = 0.63, 0.73), 0.55 (95% CI = 0.51, 0.59), 0.70 (95% CI = 0.64, 0.76), and 0.51 (95% CI = 0.47, 0.54), respectively. Conclusions: Air pollution was associated with a reduction in sleep duration among freshman students living in Beijing, China. Replication of this study is warranted among various populations within China.

Impact of Air Pollution on Sedentary Behavior: A Cohort Study of Freshmen at a University in Beijing, China.

Human populations worldwide have experienced substantial environmental issues in part due to air pollution, notably in China. Gaps in the scientific literature remain regarding the relationship between air pollution and sedentary behavior among young adults in China. The purpose of this study is to examine the effect of air pollution on sedentary behavior among college students living in Beijing, China. We conducted follow-up health surveys on 12,174 freshman students enrolled at Tsinghua University from 2013 to 2017. Sedentary behavior was measured using the short version of the International Physical Activity Questionnaire (IPAQ). Corresponding air pollution data measured by the Ministry of Environmental Protection of the People’s Republic of China were collected to include the average hourly air quality index (AQI), PM2.5, PM10, and NO2 (µg/m³). The data were analyzed using linear individual fixed-effect regressions. An increase in air pollution concentration of one standard deviation in AQI, PM2.5, PM10, and NO2 was associated with an increase in weekly total hours of sedentary behavior by 7.35 (95% confidence interval (CI) = 5.89, 8.80), 6.24 (95% CI = 5.00, 7.49), 6.80 (95% CI = 5.46, 8.15), and 7.06 (95% CI = 5.65, 8.47), respectively. In the presence of air pollution, women students tended to increase their sedentary behavior more than men. Air pollution increases sedentary behavior among freshman students living in Beijing, China. Replication of this study is warranted among various populations within China.

The impact of acute air pollution fluctuations on bronchiectasis pulmonary exacerbation: a case-crossover analysis

In bronchiectasis, exacerbations are believed to be triggered by infectious agents, but often no pathogen can be identified. We hypothesised that acute air pollution exposure may be associated with bronchiectasis exacerbations.We combined a case-crossover design with distributed lag models in an observational record linkage study. Patients were recruited from a specialist bronchiectasis clinic at Ninewells Hospital, Dundee, UK.We recruited 432 patients with clinically confirmed bronchiectasis, as diagnosed by high-resolution computed tomography. After excluding days with missing air pollution data, the final model for particles with a 50% cut-off aerodynamic diameter of 10 µm (PM10) was based on 6741 exacerbations from 430 patients and for nitrogen dioxide (NO2) it included 6248 exacerbations from 426 patients. For each 10 µg·m-³ increase in PM10 and NO2, the risk of having an exacerbation that same day increased significantly by 4.5% (95% CI 0.9-8.3) and 3.2% (95% CI 0.7-5.8) respectively. The overall (lag zero to four) increase in risk of exacerbation for a 10 μg·m-3 increase in air pollutant concentration was 11.2% (95% CI 6.0-16.8) for PM10 and 4.7% (95% CI 0.1-9.5) for NO2 Subanalysis showed higher relative risks during spring (PM10 1.198 (95% CI 1.102-1.303), NO2 1.146 (95% CI 1.035-1.268)) and summer (PM10 2.142 (95% CI 1.785-2.570), NO2 1.352 (95% CI 1.140-1.602)) when outdoor air pollution exposure would be expected to be highest.In conclusion, acute air pollution fluctuations are associated with increased exacerbation risk in bronchiectasis.

Impact of Air Pollution on Physical Activity

PURPOSE: Air pollution has become a substantial environmental issue affecting human health and health-related behavior worldwide, especially in Beijing, China. Physical activity (PA) has been well demonstrated as a means to promote people’s health and well-being and is potentially being influenced by the air pollution. Yet, the effects of air pollution on PA behavior have not been well investigated. This study examined of the impacts of air pollution on moderate to vigorous PA(MVPA) among college students in Beijing, China. METHODS: We conducted the follow-up health surveys on 9,095 freshmen from Tsinghua University in Beijing during 2013-2015, and their PA was measured by the “International Physical Activity Questionnaire” (IPAQ) questionnaire. Air pollution data included average hourly air quality index (AQI), PM2.5, PM10, SO2 and NO2 (μg/ m3) were measured by Ministry of Environmental Protection of the People’s Republic of China. The data were analyzed using the linear fixed-effect regressions. RESULTS: An one standard deviation (SD) increase in air pollution concentration in AQI, PM2.5, PM10, SO2 and NO2 was associated with a reduction in weekly total minutes of vigorous PA by 61.18, 43.14, 71.37, 20.73 and 19.66, respectively; a reduction in weekly total minutes of moderate PA by 80.10, 56.62, 93.52, 27.47 and 25.88, respectively; a reduction in weekly total minutes of MVPA by 147.17, 104.15, 171.90, 50.57 and 47.64, respectively. CONCLUSIONS: Air pollution discouraged MVPA among college students. Future studies are warranted to replicate study findings in other subpopulations and China cities, and policy interventions are urgently called to reduce air pollution level in China.

The Association between Air Pollution and Outpatient and Inpatient Visits in Shenzhen, China.

Nowadays, air pollution is a severe environmental problem in China. To investigate the effects of ambient air pollution on health, a time series analysis of daily outpatient and inpatient visits in 2015 were conducted in Shenzhen (China). Generalized additive model was employed to analyze associations between six air pollutants (namely SO2, CO, NO2, O3, PM10, and PM2.5) and daily outpatient and inpatient visits after adjusting confounding meteorological factors, time and day of the week effects. Significant associations between air pollutants and two types of hospital visits were observed. The estimated increase in overall outpatient visits associated with each 10 µg/m3 increase in air pollutant concentration ranged from 0.48% (O3 at lag 2) to 11.48% (SO2 with 2-day moving average); for overall inpatient visits ranged from 0.73% (O3 at lag 7) to 17.13% (SO2 with 8-day moving average). Our results also suggested a heterogeneity of the health effects across different outcomes and in different populations. The findings in present study indicate that even in Shenzhen, a less polluted area in China, significant associations exist between air pollution and daily number of overall outpatient and inpatient visits.

Short-Term Fluctuations in Air Pollution and Asthma in Scania, Sweden. Is the Association Modified by Long-Term Concentrations?

Background and aimsAsthma is one of the most common respiratory diseases in the world. Research has shown that temporal increases in air pollution concentrations can aggravate asthma symptoms. The aim of this study was to assess whether individuals living in areas with higher air pollution concentrations responded differently to short-term temporal exposure to air pollution than those living in lower air pollution areas.MethodThe study was designed as a case-crossover study in Scania, Sweden. Outcome data was visits to primary health care clinics with asthma as the main complaint during the years 2007 to 2010. Nitrogen dioxide levels were obtained from 21 different air pollution monitoring stations. Short-term exposure was defined as the average concentration four days prior to the visit. Data was pooled for areas above and below a two-year average NO2 concentration of 10 μg/m3, dispersion modelled with an emission database.ResultsThe short-term association between NO2 and asthma visits seemed stronger in areas with NO2 levels below 10 μg/m3, with an odds ratio (OR) of 1.15 (95% confidence interval (CI): 1.08–1.23) associated with a 10 μg/m3 increase in NO2 compared to areas above 10 μg/m3 NO2 levels, where corresponding OR of 1.09 (95% CI: 1.02–1.17). However, this difference was not statistically significant. (p = 0.13)ConclusionsThe study provided some evidence, although not statistically significant, that short-term associations between air pollution and asthma may depend on background air pollution levels. However, we cannot rule out that the association is due to other spatially dependent factors in Scania. The study should be reproduced in other study areas.

Acute Impact of Hourly Ambient Air Pollution on Preterm Birth

Background:Preterm birth is a major perinatal health problem, but factors leading to it are still not completely understood.Objectives:Our goal was to identify the relation between acute increase in ambient air pollution in a few hours before onset of labor and the risk of preterm birth.Methods:We collected registered birth outcome data and hourly ambient air pollution measurements during 2009‒2013 in Brisbane, Australia. Using a time-stratified case-crossover design and conditional logistic regression models with natural cubic splines, we assessed the shape of air pollution-preterm birth curve, after controlling for potential confounders. We also examined the effect modification of other factors.Results:The association between air pollution [nitrogen dioxide (NO2), sulfur dioxide (SO2), and carbon monoxide (CO)] and preterm birth was nonlinear. Threshold concentrations for the mean of 0‒24 hr NO2, 24‒48 hr SO2, and 24‒48 hr CO before onset of labor were 7.6 parts per billion (ppb), 3.8 ppb, and 162.5 ppb, respectively. Increases in air pollution concentrations above thresholds were associated with increased risks of preterm birth. The odds ratios of preterm birth at the 95th percentile of NO2, SO2, and CO against the thresholds were 1.17 (95% CI: 1.08, 1.27), 1.01 (95% CI: 0.99, 1.04), and 1.18 (95% CI: 1.06, 1.32), respectively. The associations were modified by demographic factors, such as maternal smoking and socioeconomic status.Conclusion:Acute increases in ambient air pollution concentrations above certain levels before onset of labor may stimulate preterm birth.Citation:Li S, Guo Y, Williams G. 2016. Acute impact of hourly ambient air pollution on preterm birth. Environ Health Perspect 124:1623–1629; http://dx.doi.org/10.1289/EHP200