Two-pollutant Models Research Articles

Constructing an Air Quality Health Index for children: A case study in Shanghai, China

BackgroundThe Air Quality Health Index (AQHI) based on the association between excess mortality risk and air pollutants was established by Canadian scientists in 2008 and it has been widely used for predicting multiple air pollutants related health risks. However, it remains unclear whether AQHI is a better indicator in predicting other health risks like respiratory diseases for vulnerable populations. ObjectiveThis study aimed to propose a case on constructing an AQHI based on the association between air pollution and hospital outpatient visits for respiratory diseases among children and to determine whether the index adequately predicts early risk of respiratory diseases in children. MethodData of air pollutants, including particulate matter of less than 2.5 μm in aerodynamic diameter (PM2.5), sulfur dioxide (SO2), nitrogen dioxide (NO2), and ozone (O3) were collected from Shanghai Environmental Monitoring Center from January 1, 2015 to December 31, 2019. Daily number of hospital outpatient visits for pediatric (0–12 years old) respiratory diseases were also obtained. Time-series analysis with a generalized additive model (GAM) during warm (Apr. to Sep.) and cool periods (Oct. to Mar.) was conducted to estimate the associations between respiratory-related hospital outpatient visits in children and the concentrations of air pollutants including PM2.5, SO2, NO2, and O3 in Shanghai from 2015 to 2018. The sum of excess risk (ER) of hospital outpatient visits in warm and cool periods was used to construct the AQHI for children (AQHIc). As AQHIc was established using the data from 2015 to 2018, we examined the validity of the index with data from 2017 to 2019. We also compared the predictive power of AQHIc and the currently used Air Quality Index (AQI) with the data of daily hospital outpatient visits from 2017 to 2019. ResultAccording to one- and two-pollutant models of GAM, the concentration-response coefficients of PM2.5, SO2, NO2, and O3 were selected to construct the AQHIc in the warm period, while only SO2, NO2, and PM2.5 were included for the construction of AQHIc in the cool period as O3 was negatively correlated with the hospital outpatient visits. There were almost linear exposure-response correlations between AQHIc and daily hospital outpatient visits. AQHIc and AQI showed similar results with the annual data in terms of model fit statistics. When the data was divided into warm and cool periods, the power of AQHIc was slightly stronger than that of AQI in predicting the air pollution-related health risks. ConclusionAQHIc we developed might comprehensively reflect the combined effects of air pollution in Shanghai and it could be a more valid prediction index for evaluating air pollution-related health risks in children.

Short-term effect of fine particulate matter and ozone on non-accidental mortality and respiratory mortality in Lishui district, China

BackgroundIn recent years, air pollution has become an imminent problem in China. Few studies have investigated the impact of air pollution on the mortality of the middle-aged and elderly people. Therefore, this study aims to evaluate the impact of PM2.5 (fine particulate matter) and O3 (ozone) on non-accidental mortality and respiratory mortality of the middle-aged and elderly people in Lishui District of Nanjing and provide the evidence for potential prevention and control measures of air pollution.MethodUsing daily mortality and atmospheric monitoring data from 2015 to 2019, we applied a generalized additive model with time-series analysis to evaluate the association of PM2.5 and O3 exposure with daily non-accidental mortality and respiratory mortality in Lishui District. Using the population attributable fractions to estimate the death burden caused by short-term exposure to O3 and PM2.5。.ResultFor every 10 μg/m3 increase in PM2.5, non-accidental mortality increased 0.94% with 95% confidence interval (CI) between 0.05 and 1.83%, and PM2.5 had a more profound impact on females than males. For every 10 μg/m3 increase in O3, respiratory mortality increased 1.35% (95% CI: 0.05, 2.66%) and O3 had a more profound impact on males than females. Compared with the single pollutant model, impact of the two-pollutant model on non-accidental mortality and respiratory mortality slightly decreased. In summer and winter as opposed to the other seasons, O3 had a more obvious impact on non-accidental mortality. The population attributable fractions of non-accidental mortality were 0.84% (95% CI:0.00, 1.63%) for PM2.5 and respiratory mortality were 0.14% (95% CI:0.01, 0.26%) for O3. For every 10 μg/m3 decrease in PM2.5, 122 (95% CI: 6, 237) non-accidental deaths could be avoided. For every 10 μg/m3 decrease in O3, 10 (95% CI: 1, 38) respiratory deaths could be avoided.ConclusionPM2.5 and O3 could significantly increase the risk of non-accidental and respiratory mortality in the middle-aged and elderly people in Lishui District of Nanjing. Exposed to air pollutants, men were more susceptible to O3 damage, and women were more susceptible to PM2.5 damage. Reduction of PM2.5 and O3 concentration in the air may have the potential to avoid considerable loss of lives.

Fine particulate matter constituents associated with emergency room visits for pediatric asthma: a time-stratified case\u2013crossover study in an urban area

BackgroundGlobal asthma-related mortality tallies at around 2.5 million annually. Although asthma may be triggered or exacerbated by particulate matter (PM) exposure, studies investigating the relationship of PM and its components with emergency department (ED) visits for pediatric asthma are limited. This study aimed to estimate the impact of short-term exposure to PM constituents on ED visits for pediatric asthma.MethodsWe retrospectively evaluated non-trauma patients aged younger than 17 years who visited the ED with a primary diagnosis of asthma. Further, measurements of PM with aerodynamic diameter of < 10 μm (PM10), PM with aerodynamic diameter of < 10 μm (PM2.5), and four PM2.5 components (i.e., nitrate (NO3−), sulfate (SO42−), organic carbon (OC), and elemental carbon (EC)) were collected between 2007 and 2010 from southern particulate matter supersites. These included one core station and two satellite stations in Kaohsiung City, Taiwan. A time-stratified case-crossover study was conducted to analyze the hazard effect of PM.ResultsOverall, 1597 patients were enrolled in our study. In the single-pollutant model, the estimated risk increase for pediatric asthma incidence on lag 3 were 14.7% [95% confidence interval (CI), 3.2–27.4%], 13.5% (95% CI, 3.3–24.6%), 14.8% (95% CI, 2.5–28.6%), and 19.8% (95% CI, 7.6–33.3%) per interquartile range increments in PM2.5, PM10, nitrate, and OC, respectively. In the two-pollutant models, OC remained significant after adjusting for PM2.5, PM10, and nitrate. During subgroup analysis, children were more vulnerable to PM2.5 and OC during cold days (< 26 °C, interaction p = 0.008 and 0.012, respectively).ConclusionsBoth PM2.5 concentrations and its chemical constituents OC and nitrate are associated with ED visits for pediatric asthma. Among PM2.5 constituents, OC was most closely related to ED visits for pediatric asthma, and children are more vulnerable to PM2.5 and OC during cold days.

Long-term exposure to ambient air pollution and bladder cancer incidence in a pooled European cohort: the ELAPSE project

BACKGROUND AND AIM: The epidemiological evidence on associations between ambient air pollution and bladder cancer is limited. We aimed to evaluate the associations between long-term exposure to ambient air pollution and bladder cancer incidence in a pooled European cohort. METHODS: We pooled data from six European cohorts enrolled between 1985 and 2005 (N = 302,493). Residential exposure to annual 2010 mean concentrations of fine particulate matter (PM2.5), nitrogen dioxide (NO2), Black Carbon (BC), warm season ozone (O3) and eight PM2.5 elemental components (copper, iron, potassium, nickel, sulfur, silicon, vanadium, and zinc) were assessed based on Europe-wide land use regression models at 100 × 100 m spatial scale. We applied Cox proportional hazard models with adjustment for potential confounders at individual- and area-level. We also performed two-pollutant models and sensitivity analyses including using exposures back-extrapolated to baseline years. RESULTS:During an average of 18.2 years follow-up, 967 bladder cancer cases were diagnosed. In single pollutant models, we observed a positive association between PM2.5 and bladder cancer incidence (Hazard Ratio (HR) and 95% confidence interval (CI): HR 1.09; 95% CI: 0.93, 1.27 per 5 µg/m3), which attenuated for PM2.5 back-extrapolated to baseline years (HR 1.06; 95% CI: 0.99, 1.14 per 5 µg/m3). Effect estimates for NO2, BC and O3 were very close to unity. Regarding elemental composition in PM2.5, we observed a positive association between zinc and bladder cancer incidence (HR 1.08; 95% CI: 1.00, 1.16 per 10 ng/m3). The effect estimates were robust in two-pollutant models and sensitivity analyses. CONCLUSIONS:There was suggestive evidence of an association between long-term exposure to PM2.5 and bladder cancer incidence, especially with zinc in PM2.5, which is primarily associated with industrial emissions. We found no evidence of an association between traffic-related air pollution and bladder cancer. KEYWORDS: Air pollution, Particulate matter, Particle components, Long-term exposure, Cancer and cancer precursors

Associations of Long-term Air Pollution Exposure and Incident Late-Life Disability in Older U.S. Adults: The Health Retirement Study

BACKGROUND AND AIM: Late-life disability is of critical concern to older adults and can reflect the cumulative burden of chronic disease over the lifespan. Although air pollution has been associated with many common chronic conditions, associations with disability are understudied. We aimed to quantify associations between long-term exposures to air pollution and late-life disability. METHODS: We used biennial data between 2000 and 2016 on self-reported Activities of Daily Living (ADL) from participants 65 years from the nationally representative Health and Retirement Study. Using a spatiotemporal prediction model, we estimated 10-year PM2.5, PM10-2.5, NO2, and O3 concentrations at participant residences. We then estimated the risk of incident ADL disability as a function of time-varying air pollution, adjusting for individual and area-level confounders and sampling weights in a Cox model. We fitted single- and two-pollutant models. RESULTS:Our study population of 16,927 adults (70+6.4 years) was predominantly non-Hispanic White (76%), Non-Hispanic Black (14%), and Hispanic White (8%) and 32% reported a new disability during follow-up. Overall, we found some evidence that air pollution was associated with an increased risk of ADL disability. After adjustment for place and PM2.5, we found that interquartile increases in PM10-2.5 and NO2 were associated with 8% (HR: 1.08 per 5 µg/m3, 95% CI: 1.01, 1.17) and 9% (HR: 1.09 per 6 ppb, 95% CI: 1.00, 1.19) greater hazards of ADL, respectively, with similar findings in the single pollutant models. PM2.5 and O3 were not associated with higher hazards of ADL in single or multipollutant models after detailed adjustment for place. CONCLUSIONS:This prospective study in a nationally representative sample of older adults found some evidence that higher levels of some but not all long-term air pollutants assessed are associated with increased risk of late-life disability. KEYWORDS: Air Pollution, Long-Term Exposure, Activities of Daily Living

Impacts of Ambient Carbon Monoxide on Hospital Admissions and Hospitalization Expenditures for Three Cardiorespiratory Diseases in 74 Cities of China

BACKGROUND AND AIM: Evidence about health burden and economic loss of cardiorespiratory diseases (CRDs) caused by ambient carbon monoxide (CO) is sparse. We aimed to assess health burden as well as economic loss caused by coronary heart disease (CHD), stroke and lower respiratory infections (LRI) attributed to ambient CO in multiple cities in China. METHODS: Hospital admission and expenditures data were obtained from urban employee-based basic medical insurance scheme (UEBMI) of the national health insurance system in China. We performed a three-stage time-series analysis approach based on Generalized Linear Model controlling for potential confounding factors to examine the association between ambient CO and hospitalization data of CHD, stroke and LRI in 74 cities of China from January 1, 2015 to December 31, 2017. We conducted subgroup analyses by geographical region, gender and age (15-64 and ≥65), and tested the robustness of the results in two-pollutant models and sensitive analyses. RESULTS:We found that the average daily concentration of ambient CO across 74 cities from 2015 to 2017 was 1.10 mg/m³ (SD: 0.62). For a 1 mg/m³ increase in CO concentrations, the largest excess risks (ERs) were 3.82% (95% CI: 1.27% to 6.44%) at lag04 for CHD, 3.14% (95% CI: 1.90% to 4.38%) at lag0 for stroke and 2.71% (95% CI: 1.21% to 4.23%) at lag01 for LRI. Moreover, we observed that 4.50%, 3.33% and 2.97% of CHD, stroke and LRI related hospital admissions during 2015 to 2017 could be attributed to ambient CO in included cities, and the annualized attributable numbers of hospitalization expenditures were enormous, with 490 million CNY (US$ 73 M), 371 million CNY (US$ 55 M) and 217 million CNY (US$ 32 M) for CHD, stroke and LRI, respectively. CONCLUSIONS:Our study provides robust evidence for substantial excess hospitalization burden of CHD, stroke and LRI attributable to ambient CO based on multi-city analyses. KEYWORDS: Air pollution, Cardiovascular diseases, Environmental epidemiology, Traffic-related, Respiratory outcomes

Prenatal exposure to PM2.5 constituents and children’s growth trajectory in the first two years: a birth cohort study

BACKGROUND AND AIM: Limited studies on the associations of prenatal exposure to fine particulate matters (PM2.5) with children’s growth reported inconsistent results. No study evaluated the effects of specific constituents of PM2.5 on children’s growth trajectory, which may contribute to discrepancies among PM2.5 studies. We aimed to examine the association of prenatal exposure to PM2.5 constituents and children’s growth trajectory in the first two years. METHODS: The study was based on a birth cohort(2014-2017) in China, involving 18,667 mothers with their children who were followed to two years old. We estimated prenatal PM2.5 constituents [organic carbon(OC), elemental carbon(EC), sulfate(SO42-), nitrate(NO3-), and ammonium (NH4+)] concentrations based on maternal home addresses. Height(or length) and weight of children were repeatedly measured at the age of 3,6,9,12,18,24 months. We calculated body mass index (BMI) Z-score based on the WHO Standards. Latent class growth modeling was used to identify children’s BMI Z-score trajectory. Multinomial logistic regression was used to examine the association of prenatal exposure to PM2.5 constituents with children’s growth trajectories. RESULTS:Three BMI Z-score trajectories were identified: stable trajectory (n=15265,81.9%), decreased trajectory(n=2130,11.4%), and increased trajectory(n=1234,6.6%). Compared with stable trajectory, an interquartile range (IQR) increase in prenatal exposure to PM2.5, NH4+, and NO3- was associated with 0.847[95% confidence interval(95%CI):0.744,0.965], 0.806(95%CI:0.710,0.915), and 0.677(95%CI: 0.603,0.761) lower risk of increased trajectory, respectively. An IQR increase in prenatal exposure to OC and SO42- was associated with 1.395(95%CI:1.236,1.575) and 1.562 (95%CI:1.324,1.842) higher risk of increased trajectory, respectively. The results were robust in two-pollutant models. We did not observe significant associations between prenatal exposure to PM2.5 constituents and risk of decreased trajectory. CONCLUSIONS:The study suggested that prenatal exposure to PM2.5 and its constituents was associated with risk of children’s increased growth trajectory in the first two years. Public health policy on regulation of harmful PM2.5 constituents should be developed to protect early-life health of children. KEYWORDS: particulate matters, constituents, body mass index, growth trajectory, children

Associations between air pollution and depressive symptoms in older adults: a repeated measurement study

BACKGROUND AND AIM: Epidemiological studies concerning the relationships between different exposure windows of air pollution and symptoms of depression in older adults are limited. Hence, we investigate the relations between short-term and long-term exposure to ambient air pollution (PM10, O3, SO2, CO, and NOX) and depressive symptoms in a community-dwelling, free-living elderly population. METHODS: Study participants were in a multiple-wave representative sample (Taiwan Longitudinal Study on Aging, n=1956). In four surveys between 1996 and 2007, their depressive symptoms were assessed using the 10-itemed Center for Epidemiologic Studies Depression (CESD-10). We estimated air pollution from 1993 to 2007, including daily concentrations of five air pollutants from air quality monitoring stations, based on the administration zone of each participant’s residence. Generalized linear mixed models were applied to examine these associations after adjusting for covariates at different exposure windows (7-, 14-, 21-, 30-, 60-, 90-, 180-days, and 1-year moving averages). RESULTS:In one-pollutant model, the short-term and long-term exposure to CO and NOX were associated with increased risk of depressive symptoms; the ORs and 95% CIs for each 1 ppm increment in CO at 7-, 14-, 21-, 30-, 60-, 90-, 180-days, and 1-year moving averages were 2.23 (1.53, 3.27), 2.27 (1.63, 3.16), 2.19 (1.62, 2.96), 2.23 (1.62, 3.07), 2.12 (1.55, 2.90), 2.15 (1.55, 2.98), 2.14 (1.53, 2.99), 2.13 (1.56, 2.91), respectively. Moreover, for each 10 ppb increment in NOX at series exposure windows were 1.16 (1.08, 1.25), 1.18 (1.11, 1.26), 1.17 (1.11, 1.24), 1.18 (1.11, 1.25), 1.18 (1.11, 1.26), 1.18 (1.11, 1.26), 1.18 (1.11, 1.26), 1.18 (1.11, 1.26), respectively. In two-pollutant model, only the associations of exposure to NOX with depressive symptoms remained robust after adjustment for any other pollutant. CONCLUSIONS:Exposure to traffic-related air pollutants could increase the risk for depressive symptoms in older adults. KEYWORDS: air pollution, depressive symptoms, older adults, repeated measurement.

Exposure to ultrafine particles and the incidence of asthma in children: A population-based open cohort study in Montreal, Canada

BACKGROUND AND AIM: Asthma is the most prevalent chronic respiratory disease in children and represents an important burden on health care systems. The association between air pollution and asthma is well established, however the role of ultrafine particles (UFPs) remains unclear. We evaluated the association between long-term exposure to UFPs and childhood-onset asthma in a population-based birth cohort in Montreal, Canada. METHODS: The cohort was constructed from the Quebec Integrated Chronic Disease Surveillance System and included all children born in Quebec between 2000 and 2015 who were resident of Montreal. Case definitions consisted of at least two physician claims with a diagnosis of asthma within a two-year period or one hospital discharge with a primary or secondary diagnosis of asthma. Annual concentrations of UFPs and of nitrogen dioxide (NO2) were estimated from land use regression models developed for Montreal and assigned at participants’ residence over the follow-up using their residential postal codes. The association between UFPs and childhood asthma onset was estimated with a Cox proportional hazards model stratified for sex and adjusted for age, neighbourhood material and social deprivation, calendar year and co-exposure to NO2. RESULTS:The cohort included 352,966 children, with 30,825 incident asthma cases. The annual average concentrations were 24,427 particles/cm3 for UFPs and 18.55 ppb for NO2. In the single pollutant model, the adjusted hazard ratio (HR) per interquartile range (IQR) increase in UFPs was 0.990 (95% CI: 0.983, 0.997). The two-pollutant model showed no association for UFPs (HR per IQR = 0.986; 95% CI: 0.979, 0.997) but a positive association for NO2 (HR per IQR = 1.038; 95% CI: 1.013, 1.051). CONCLUSIONS:In this population-based birth cohort, childhood asthma onset was not associated with UFPs but positively associated with NO2 estimated at participants’ residential location. KEYWORDS: Air pollution, Particulate matter, Asthma, Respiratory outcomes, Children's environmental health

Associations between Short-Term Exposure to Particulate Matter and Ultrafine Particles with Lung Function in Schoolchildren from the German CorPuScula Study

BACKGROUND AND AIM: Short-term exposure to particulate matter (PM) has been associated with impaired lung function, but exposure to ultrafine particles (UFP) has been less well examined in children. METHODS: We analyzed data from 50 schoolchildren (ages 6-10) at an elementary school from the German CorPuScula study conducted from 2001 to 2002. Spirometry (VC, FEV1, MEF25-75) and body plethysmography (specific airway resistance) were performed to assess lung function. PM exposure (diameter ≤10 µm; µg/m (PM10), diameter ≤2.5 µm; µg/m³ (PM2.5)) was measured at school over the full study period, and UFP exposure was measured for six months. Mean exposures during the day of examination (9-21h) as well as one- and two-day lags were assessed. Further, individual mean UFP (1- and 3-h), and PM10 (3-, 12- and 24-h) exposures before examination were calculated. Associations between short-term air pollution and lung function were assessed using generalized estimating equation models with an autoregressive correlation matrix, adjusted for day of the week, study day and physiological equivalent temperature index using splines. Two-pollutant models adjusted for centrally-monitored NO2 were performed. RESULTS:For PM, median PM10 levels were 17.4 µg/m³ (nobs=961, average of 20 tests/child). For UFP, median UFP concentration was 21,826 particles/mL (nobs=421, average of 8 tests/child). PM and UFP showed mixed associations with spirometry outcomes. For PM, we observed weak positive associations with airway resistance for 12-h and 24-h PM10 (e.g. 7.4 % [95% CI: 1.9%; 13.3%] increase in airway resistance per 24.9 µg/m³ increase in 12-h PM10) and weak inverse associations for the two-day lag. While results for 12-h and 24h PM10 before testing were robust to NO2 adjustment, inverse associations for two-day lags disappeared. For UFP, no associations with airway resistance were visible. CONCLUSIONS:We observed mixed results for spirometry outcomes. PM10 was associated with increased airway resistance. No associations were visible for UFPs. KEYWORDS: Short-term exposure, Particulate matter, Respiratory outcomes

Long-term exposure to air pollution and liver cancer incidence in six European cohorts.

Particulate matter air pollution and diesel engine exhaust have been classified as carcinogenic for lung cancer, yet few studies have explored associations with liver cancer. We used six European adult cohorts which were recruited between 1985 and 2005, pooled within the "Effects of low-level air pollution: A study in Europe" (ELAPSE) project, and followed for the incidence of liver cancer until 2011 to 2015. The annual average exposure to nitrogen dioxide (NO2 ), particulate matter with diameter <2.5μm (PM2.5 ), black carbon (BC), warm-season ozone (O3 ), and eight elemental components of PM2.5 (copper, iron, zinc, sulfur, nickel, vanadium, silicon, and potassium) were estimated by European-wide hybrid land-use regression models at participants' residential addresses. We analyzed the association between air pollution and liver cancer incidence by Cox proportional hazards models adjusting for potential confounders. Of 330 064 cancer-free adults at baseline, 512 developed liver cancer during a mean follow-up of 18.1 years. We observed positive linear associations between NO2 (hazard ratio, 95% confidence interval: 1.17, 1.02-1.35 per 10μg/m3 ), PM2.5 (1.12, 0.92-1.36 per 5μg/m3 ), and BC (1.15, 1.00-1.33 per 0.5 10-5 /m) and liver cancer incidence. Associations with NO2 and BC persisted in two-pollutant models with PM2.5 . Most components of PM2.5 were associated with the risk of liver cancer, with the strongest associations for sulfur and vanadium, which were robust to adjustment for PM2.5 or NO2 . Our study suggests that ambient air pollution may increase the risk of liver cancer, even at concentrations below current EU standards.

The association between fine particulate matter and acute lower respiratory infections in Yancheng City, China.

Due to the rapid economic development and acceleration of industrialization, most cities in China are experiencing severe air pollution. Exposure to fine particulate matter (PM2.5) has been associated with acute lower respiratory tract infection (ALRI). To estimate associations between short-term exposure to PM2.5 and ALRI hospitalization in Yancheng City, China. This was a 6-year time-series study from 2014 to 2019. Data on hospitalization were collected from four high-ranked general hospitals, including for community-acquired pneumonia (CAP), acute exacerbation of chronic bronchitis (AECB), acute exacerbation of chronic obstructive pulmonary disease (AECOPD), and acute exacerbation of bronchiectasis (AEB), and the sum was termed total ALRIs. We obtained pollutant exposure data from five fixed monitoring stations. The association between PM2.5 and ALRI hospitalization was estimated using the generalized linear model with quasi-Poisson regression. Two-pollutant models were applied to test the robustness of the observed correlations. Subgroup analyses included sex, age, and season. During the study period, a total of 43,283 cases of total ALRIs were recorded. The average annual mean PM2.5 concentration was 45.4 ± 32.3 μg/m3. A 10-μg/m3 increase in PM2.5 concentration (lag 0) was significantly associated with increases in hospitalizations for total ALRIs (at 0.73%; 95% CI: 0.40%, 1.06%), in CAP (at 0.80%; 95% CI: 0.02%, 1.57%), in for AECOPD (1.08%; 95% CI: 0.38%, 1.78%), and AECB (0.67%; 95% CI: 0.23%, 1.11%). The estimated effects for total ALRIs and AECB were relatively robust with adjustment for other air pollutants. Associations between PM2.5 and total ALRIs were stronger in females, in the elderly, and in the cold season. PM2.5 exposure was significantly associated with ALRI morbidity, and females and older people were more susceptible to PM2.5 air pollution, especially in the cold season.

Long-term exposure to low-level air pollution and incidence of asthma: the ELAPSE project.

Long-term exposure to ambient air pollution has been linked to childhood-onset asthma, although evidence is still insufficient. Within the multicentre project Effects of Low-Level Air Pollution: A Study in Europe (ELAPSE), we examined the associations of long-term exposures to particulate matter with a diameter <2.5 µm (PM2.5), nitrogen dioxide (NO2) and black carbon (BC) with asthma incidence in adults. We pooled data from three cohorts in Denmark and Sweden with information on asthma hospital diagnoses. The average concentrations of air pollutants in 2010 were modelled by hybrid land-use regression models at participants' baseline residential addresses. Associations of air pollution exposures with asthma incidence were explored with Cox proportional hazard models, adjusting for potential confounders. Of 98 326 participants, 1965 developed asthma during a mean follow-up of 16.6 years. We observed associations in fully adjusted models with hazard ratios of 1.22 (95% CI 1.04-1.43) per 5 μg·m-3 for PM2.5, 1.17 (95% CI 1.10-1.25) per 10 µg·m-3 for NO2 and 1.15 (95% CI 1.08-1.23) per 0.5×10-5 m-1 for BC. Hazard ratios were larger in cohort subsets with exposure levels below the European Union and US limit values and possibly World Health Organization guidelines for PM2.5 and NO2. NO2 and BC estimates remained unchanged in two-pollutant models with PM2.5, whereas PM2.5 estimates were attenuated to unity. The concentration-response curves showed no evidence of a threshold. Long-term exposure to air pollution, especially from fossil fuel combustion sources such as motorised traffic, was associated with adult-onset asthma, even at levels below the current limit values.

Relationship between fine particulate air pollution and hospital admissions for depression: a case-crossover study in Taipei

ABSTRACT There are few apparent studies regarding the association between fine particulate matter (PM2.5) air pollution and development of depression. Data obtained from epidemiological studies are inconsistent and controversial. The aim of this case-crossover study was to examine the association between short-term exposure to PM2.5 alone and in combination with other pollutants and frequency of hospitalizations for depression from 2009 to 2013 in Taipei, Taiwan. In the single pollutant model without adjustment for other pollutants, 17% and 4% increase in admissions attributed to depression correlated with interquartile range (IQR) rise in PM2.5 levels was noted on warm and cool days, respectively. Data were also analyzed using two-pollutant models and it was found that on warm days, the association continued to be significant after including one of the following pollutants: sulfur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3) or carbon monoxide (CO). On cool days, the significance was lost. In conclusion, the relationship between ambient outdoor PM2.5 exposure and rates of hospitalization for depression appeared to be temperature dependent in Taipei. Further research is needed to verify these observations as well as to distinguish the relative contributions of PM2.5 and temperature to development for hospital admissions for depression.

Association of persistent organic pollutants with sensorimotor neuropathy in participants with and without diabetes or prediabetes: Results from the population-based KORA FF4 study.

Concentrations of persistent organic pollutants (POPs) have been associated with an increased type 2 diabetes (T2D) risk. It remains unclear whether POPs are also associated with the risk of diabetes complications including neuropathy and evidence on this topic is scarce. We aimed to investigate the hypothesis that low-dose background concentrations of POPs were positively associated with distal sensorimotor polyneuropathy (DSPN). This cross-sectional study was based on data from the second follow-up (FF4, 2013-2014, N=2279) of the population-based KORA S4 study (Augsburg, Germany). The study sample consisted of 200 participants, including four groups of 50 persons each with known T2D, prediabetes, newly diagnosed diabetes, and normal glucose tolerance (NGT) based on an oral glucose tolerance test. We analyzed the association of six most abundant serum concentrations of POPs, including polychlorinated biphenyls (PCBs) as well as organochlorine (OC) pesticides, with DSPN by multivariable logistic regression adjusted for age, sex, glycaemic status, body mass index, physical activity, smoking and alcohol consumption. We assessed effect modification by age, sex, glycaemic status and obesity and conducted two-pollutant models to check the robustness of the estimates. For all pollutants, the main models indicated no significant association of having DSPN but pointed to rather decreased odds for DSPN. Two-pollutant models supported these findings, though only the association between the combination of PCB-138 and beta-hexachlorocyclohexane (β-HCH) (OR: 0.59; 95% CI: 0.35-0.99) with DSPN became significant. No effect modification was found by age, sex, glycaemic status and obesity. Low-dose concentrations of POPs were not associated with increased odds of having DSPN in T2D, prediabetes and NGT.

An association between PM2.5 and pediatric respiratory outpatient visits in four Chinese cities

BackgroundThe effects of exposure to particulate matter with aerodynamic diameter less than 2.5 μm (PM2.5) on children's respiratory system were investigated in numerous epidemiological literatures. However, studies on the association between PM2.5 and pediatric outpatient visits for respiratory diseases, especially considering the multicenter studies were limited in China. ObjectivesTo study the association between the short-term exposure to PM2.5 and the number of children's outpatient visits for respiratory diseases in four Chinese cities as well as the pooled health effects. MethodsData of pediatric outpatient visits for respiratory diseases (RD, ICD: J00-J99) from representative hospitals in Shijiazhuang (SJZ), Xi'an (XA), Nanjing (NJ) and Guangzhou (GZ) in China from 2015 to 2018 were collected and the air quality data for the same period were collected from environmental protection departments. Generalized additive model (GAM) with quasi-Poisson regression was conducted to analyze the effects of PM2.5 on the number of pediatric outpatient visits in each city. Single-day lag model (lag0 to lag7) and moving average lag model (lag01 and lag07) were used to examine the lag effects and cumulative effects. Random-effects meta-analysis was used to pool the estimated risks of four cities. The interactions between PM2.5 and temperature were also explored. ResultsThe average daily/total outpatient visits for RD, in SJZ, XA, NJ and GZ from 2015 to 2018 were 854.2/1,245,384, 2353.9/3,439,025, 1267.2/1,851,438 and 1399.5/2,044,740 respectively. The percentages of acute upper respiratory infections (URD, ICD: J00-J06) and other acute lower respiratory infections (LRD, ICD: J20-J22) in RD were 33%, 13% (SJZ), 43%, 32% (XA), 26%, 21% (NJ) and 54%, 26% (GZ). The largest pooled estimates of single-day lag effects for RD, URD, and LRD were at lag0, lag0 and lag1. Every 10 μg/m3 increase in PM2.5 concentration was associated with a 0.46% (95%CI: 0.21%–0.70%), 0.50% (95%CI: 0.19%–0.81%) and 0.42% (95%CI: 0.06%–0.79%) increased number of outpatient visits significantly. While max cumulative effects which were all at lag 07 were 1.10% (95%CI: 0.46%–1.74%), 0.96% (95%CI: 0.20%–1.73%) and 1.06% (95%CI: 0.12%–2.00%). Less polluted cities (GZ and NJ) showed greater city-specific excess risks, but the excess risks significantly decreased after adjusting for NO2 in two-pollutant models. Generally, PM2.5 showed larger health hazards on lower temperature days. ConclusionsOur study showed that exposure to the ambient PM2.5 was associated with the increase of the number of outpatient visits with pediatric respiratory diseases in four Chinese cities. The health effects of PM2.5 may not be independent of other air pollutants and could be modified by temperature.

Association between short-term exposure to sulfur dioxide and carbon monoxide and ischemic heart disease and non-accidental death in Changsha city, China.

BackgroundTo investigate the effects of short-term exposure to sulfur dioxide (SO2) and carbon monoxide (CO) in the central and southern China areas on ischemic heart disease (IHD) and non-accidental deaths.MethodWe investigated the associations between short-term exposure to SO2 and CO in a city in south-central China and IHD and non-accidental death using a time-series design and generalized additive models with up to a 5-day lag adjusting for day of the week, temperature, air pressure, wind speed, and relative humidity. The relative risks of IHD and non-accidental death per 10-unit increase in SO2 and CO were derived from zero to five days in single-pollutant models.ResultsBetween 2016 and 2018, a total of 10,507 IHD and 44,070 non-accidental deaths were identified. The largest significant relative risk for IHD death was lag 02 for both SO2 (1.080; 95% confidence interval: 1.075–1.084) and CO (5.297; 95% confidence interval: 5.177–5.418) in single-pollutants models. A significant association was shown at all lag multiple-day moving averages. Two-pollutant models identified an association between SO2 and mortality when adjusting for CO. In stratified analyses, SO2 exhibited a stronger association with death during the cold season, while CO exhibited a stronger association with mortality from IHD during the warm season. The risk of death was more robust in the elderly for both pollutants, but was greater in men for CO and in women for SO2.ConclusionsOverall, we found an association between short-term exposure to low-level SO2 and CO and the risk of IHD and non-accidental death.

Long-Term Exposure to Fine Particle Elemental Components and Natural and Cause-Specific Mortality-a Pooled Analysis of Eight European Cohorts within the ELAPSE Project.

Background:Inconsistent associations between long-term exposure to particles with an aerodynamic diameter [fine particulate matter ()] components and mortality have been reported, partly related to challenges in exposure assessment.Objectives:We investigated the associations between long-term exposure to elemental components and mortality in a large pooled European cohort; to compare health effects of components estimated with two exposure modeling approaches, namely, supervised linear regression (SLR) and random forest (RF) algorithms.Methods:We pooled data from eight European cohorts with 323,782 participants, average age 49 y at baseline (1985–2005). Residential exposure to 2010 annual average concentration of eight components [copper (Cu), iron (Fe), potassium (K), nickel (Ni), sulfur (S), silicon (Si), vanadium (V), and zinc (Zn)] was estimated with Europe-wide SLR and RF models at a scale. We applied Cox proportional hazards models to investigate the associations between components and natural and cause-specific mortality. In addition, two-pollutant analyses were conducted by adjusting each component for mass and nitrogen dioxide () separately.Results:We observed 46,640 natural-cause deaths with 6,317,235 person-years and an average follow-up of 19.5 y. All SLR-modeled components were statistically significantly associated with natural-cause mortality in single-pollutant models with hazard ratios (HRs) from 1.05 to 1.27. Similar HRs were observed for RF-modeled Cu, Fe, K, S, V, and Zn with wider confidence intervals (CIs). HRs for SLR-modeled Ni, S, Si, V, and Zn remained above unity and (almost) significant after adjustment for both and . HRs only remained (almost) significant for RF-modeled K and V in two-pollutant models. The HRs for V were 1.03 (95% CI: 1.02, 1.05) and 1.06 (95% CI: 1.02, 1.10) for SLR- and RF-modeled exposures, respectively, per , adjusting for mass. Associations with cause-specific mortality were less consistent in two-pollutant models.Conclusion:Long-term exposure to V in was most consistently associated with increased mortality. Associations for the other components were weaker for exposure modeled with RF than SLR in two-pollutant models. https://doi.org/10.1289/EHP8368

NO2 exposure increases eczema outpatient visits in Guangzhou, China: an indication for hospital management

BackgroundAmbient nitrogen dioxide (NO2) is a common air pollutant in developing countries and causes skin conditions, but its effect on eczema in subtropical areas is not clear in China.ObjectTo measure the effect of short-term exposure of NO2 on the incidence of eczema and the change of outpatient visits.MethodsData of daily temperature, air pollutants, and outpatient visits from 2013 to 2018 were collected in a row. The generalized additive model (GAM) and Poisson distribution were used to assess the association between short-term exposure of NO2 and the outpatient visits of patients with eczema. The cumulative exposure effect of lag 0–3 days and the displacement effect of NO2 and other pollutants were considered as well. A single pollutant model was used to examine the independent association, and a two-pollutant model was adopted to control the confounding effect.ResultsThe daily outpatient visits of eczema increased from 75.26 to 190.85 from 2013 to 2018 (P < 0.001). The combined influence of NO2 and the related pollutant exerted a stronger influence on the incidence of eczema. The maximum effect of NO2 appeared on the exposed day.(lag 0) and disappeared on day 4 (lag 3). The children and seniors were more vulnerable to NO2 exposure.ConclusionExposure to NO2 is tightly associated with eczema incidence and outpatient visits. The hospitals should react to the visit fluctuations and adjust physician duty shifts to improve outpatient service efficiency.

A Population-Based Cohort Study of Respiratory Disease and Long-Term Exposure to Iron and Copper in Fine Particulate Air Pollution and Their Combined Impact on Reactive Oxygen Species Generation in Human Lungs.

Metal components in fine particulate matter (PM2.5) from nontailpipe emissions may play an important role in underlying the adverse respiratory effects of PM2.5. We investigated the associations between long-term exposure to iron (Fe) and copper (Cu) in PM2.5 and their combined impact on reactive oxygen species (ROS) generation in human lungs, and the incidence of asthma, chronic obstructive pulmonary disease (COPD), COPD mortality, pneumonia mortality, and respiratory mortality. We conducted a population-based cohort study of ∼0.8 million adults in Toronto, Canada. Land-use regression models were used to estimate the concentrations of Fe, Cu, and ROS. Outcomes were ascertained using validated health administrative databases. We found positive associations between long-term exposure to Fe, Cu, and ROS and the risks of all five respiratory outcomes. The associations were more robust for COPD, pneumonia mortality, and respiratory mortality than for asthma incidence and COPD mortality. Stronger associations were observed for ROS than for either Fe or Cu. In two-pollutant models, adjustment for nitrogen dioxide somewhat attenuated the associations while adjustment for PM2.5 had little influence. Long-term exposure to Fe and Cu in PM2.5 and estimated ROS concentration in lung fluid was associated with increased incidence of respiratory diseases, suggesting the adverse respiratory effects of nontailpipe emissions.