Short-term joint effects of ambient air pollutants on emergency department visits for respiratory and circulatory diseases in Colombia, 2011-2014

Health effects of air pollutant mixtures (volatile organic compounds, particulate matter, sulfur and nitrogen oxides) - a review of the literature

The health risks associated with individual air pollutant exposures have been studied and documented, but in real-life, the population is exposed to a multitude of different substances, designated as mixtures. A body of literature on air pollutants indicated that the next step in air pollution research is investigating pollutant mixtures and their potential impacts on health, as a risk assessment of individual air pollutants may actually underestimate the overall risks. This review aims to synthesize the health effects related to air pollutant mixtures containing selected pollutants such as: volatile organic compounds, particulate matter, sulfur and nitrogen oxides. For this review, the PubMed database was used to search for articles published within the last decade, and we included studies assessing the associations between air pollutant mixtures and health effects. The literature search was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A number of 110 studies were included in the review from which data on pollutant mixtures, health effects, methods used, and primary results were extracted. Our review emphasized that there are a relatively small number of studies addressing the health effects of air pollutants as mixtures and there is a gap in knowledge regarding the health effects associated with these mixtures. Studying the health effects of air pollutant mixtures is challenging due to the complexity of components that mixtures may contain, and the possible interactions these different components may have.

High altitude air pollution and respiratory disease: Evaluating compounded exposure events and interactions

Today, air pollution remains a significant issue, particularly in high-altitude areas where its impact on respiratory disease remains incompletely explored. This study aims to investigate the association between various air pollutants and outpatient visits for respiratory disease in such regions, specifically focussing on Xining from 2016 to 2021. By analysing over 570,000 outpatient visits using a time-stratified case-crossover design and conditional logistic regression, we assessed the independent effects of pollutants like PM2.5, PM10, SO2, NO2, and CO, as well as their interactions. The evaluation of interactions employed measures such as relative excess odds due to interaction (REOI), attributable proportion due to interaction (AP), and synergy index (S). We also conducted a stratified analysis to identify potentially vulnerable populations. Our findings indicated that exposure to PM2.5, PM10, SO2, NO2, and CO significantly increased outpatient visits for respiratory disease, with odds ratios (ORs) of 2.40 % (95 % CI: 2.05 %, 2.74 %), 1.07 % (0.98 %, 1.16 %), 3.86 % (3.23 %, 4.49 %), 4.45 % (4.14 %, 4.77 %), and 6.37 % (5.70 %, 7.04 %), respectively. However, exposure to O3 did not show a significant association. We found significant interactions among PM2.5, SO2, NO2, and CO, where combined exposure further exacerbated the risk of respiratory diseases. For example, in the combination of PM2.5 and SO2, the REOI, AP, and S were 0.07 (95 % CI: 0.06, 0.09), 0.07 (0.06, 0.07), and 1.07 (1.05, 1.09), respectively. Additionally, elderly individuals and females were more sensitive to these pollutants, but no statistically significant interaction effects were observed between different age and gender groups. In conclusion, our study highlights the strong link between air pollution and respiratory disease in high-altitude areas, with combined pollutant exposure posing an even greater risk. It underscores the need for enhanced air quality monitoring and public awareness campaigns, particularly to protect vulnerable populations like the elderly and females.

Environmental injustice in the air quality for digital platform delivery workers in Bogotá, Colombia, 2021

Introduction

Air quality is a matter of interest for public health due to its rapid deterioration in low- and middle-income countries and the effects of polluted air on the health of populations.

Objective

To explore the air quality conditions in which digital platform delivery workers carry out their work, evaluating the localities of Kennedy and Usaquén in Bogotá, 2021.

Materials and methods

We developed a mixed parallel convergent study based on four sources of information: 1) Ethnographic observation in five commercial locations of the two localities; 2) Monitoring of PM10 and PM2.5 in 56 delivery routes using a low-cost sensor; 3) Daily logs of the routes to support the device data interpretation, and 4) A semi-structured interview applied to the drivers to explore their danger perception during the routes.

Results

We identified elements causing environmental injustice among digital platform delivery workers between the two study locations. The routes made by the delivery drivers in the locality of Kennedy registered higher concentrations of PM10 and PM2.5, compared to the values observed in Usaquén. The sources of air pollution identified by the delivery drivers through ethnographic observation and the router logbook showed the worst parameters in Kennedy.

Conclusions

We evidenced that air quality, urban equipment, road infrastructure, mobile sources, and geospatial location are elements that mark the presence of environmental injustice for the digital platform delivery drivers in the studied localities. To reduce this inequity, it is necessary for digital delivery platforms and the district government to implement strategies that reduce the exposure and emission of air pollutants to protect the health of digital platform delivery workers.

Short-Term Interaction Effects of PM2.5 and O3 on Daily Mortality: A Time-Series Study of Multiple Cities in China

In recent years, PM2.5 and O3 have been the two main pollutants affecting public health in China, but the interaction of the two pollutants on human health remains unclear. A two-stage analytical approach was used to investigate the relationships of PM2.5-O3 co-pollution with nonaccidental, cardiovascular, and respiratory mortality levels across 14 cities in China. We first utilized a generalized additive model (GAM) to determine the city-specific associations of PM2.5 and O3 with daily mortality. The associations were then combined at the national and regional levels using meta-analysis. To investigate the potential interactions between the two pollutants and cause-specific mortality, we performed stratified analyses by co-pollutant exposure levels and the synergy index (SI) (SI > 1 indicates a synergistic interaction). The effect of changes in the two pollutants' concentrations (in 10 μg/m3 increases) on mortality was assessed. The stratification analysis results suggested that each 10 μg/m3 increase in PM2.5 at lag0-1 (lag01) in the low, moderate, and high strata of the O3 concentrations increased nonaccidental mortality by 0.07% (95% confidence interval: -0.03%, 0.17%), 0.33% (0.13%, 0.53%), and 0.68% (0.30%, 1.06%), respectively, with significant between-group differences (p < 0.001). Moreover, each 10 μg/m3 increase in O3 (lag01) in the low, moderate, and high strata of the PM2.5 concentrations increased nonaccidental mortality by 0.15% (-0.06%, 0.36%), 0.53% (0.19%, 0.87%), and 0.75% (0.14%, 1.36%), respectively, with significant between-group differences (p < 0.001). We also found substantial synergistic interactions between the two pollutants and nonaccidental, cardiovascular, and respiratory mortality levels, with SI values of 1.48, 1.51, and 1.33, respectively. Additionally, a subgroup analysis revealed that the interaction of these two pollutants on nonaccidental mortality were greater in South China compared to elsewhere, and during the warm season compared to during the cold season. Our findings suggested that the simultaneous control of PM2.5 and O3 within the context of combined air pollution could significantly decrease the disease risk, especially in southern China and during the warm season.

Combined effect of changes in NO2, O3, PM2.5, SO2 and CO concentrations on small airway dysfunction

BACKGROUND AND OBJECTIVE

When multiple complex air pollutants are combined in real-world settings, the reliability of estimating the effect of a single pollutant is questionable. This study aimed to investigate the combined effects of changes in air pollutants on small airway dysfunction (SAD).

METHODS

We analysed Korea National Health and Nutrition Examination Survey (KNHANES) V-VIII database from 2010 to 2018 to elucidate the associations between annual changes in air pollutants over a previous 5-year period and small airway function. We estimated the annual concentrations of five air pollutants: NO2, O3, PM2.5, SO2 and CO. Forced expiratory flow between 25% and 75% of vital capacity (FEF25%-75%) <65% was defined as SAD. Using the quantile generalized-Computation (g-Computation) model, the combined effect of the annual changes in different air pollutants was estimated.

RESULTS

A total of 29,115 individuals were included. We found significant associations between SAD and the quartiles of annual changes in NO2 (OR = 1.10, 95% CI = 1.08-1.12), O3 (OR = 1.03, 95% CI = 1.00-1.05), PM2.5 (OR = 1.03, 95% CI = 1.00-1.05), SO2 (OR = 1.04, 95% CI = 1.02-1.08) and CO (OR = 1.16, 95% CI = 1.12-1.19). The combined effect of the air pollutant changes was significantly associated with SAD independent of smoking (OR = 1.31, 95% CI = 1.26-1.35, p-value <0.001), and this trend was consistently observed across the entire study population and various subgroup populations. As the estimated risk of SAD, determined by individual-specific combined effect models, increased and the log odds for SAD increased linearly.

CONCLUSION

The combined effect of annual changes in multiple air pollutant concentrations were associated with an increased risk of SAD.

Effect of short-term exposure to air pollution on hospital admission for cardiovascular disease: A time-series study in Xiangyang, China

BACKGROUND

Data on the relationship between short-term exposure to air pollution and cardiovascular diseases (CVDs) and the potential modifying factors are limited and inconsistent.

OBJECTIVE

To explore the relationship between short-term exposure to air pollution and CVD risk, and potential modification effect factors.

METHOD

A time series study was conducted on 52,991 hospital admissions for CVD from 2015 to 2019 in Xiangyang City, China. Air pollution data from four national fixed monitoring stations were collected to estimate exposure level in Xiangyang City. A quasi-Poisson generalized additive model incorporating a distributed lag nonlinear model was applied to evaluate the association between air pollution and CVD risk. The potential modification effect of sex, age, and season on the above associations was also evaluated.

RESULTS

CVD risk was positively associated with air pollution. Peak associations in single lag day structures were observed for particulate matter ≤10 μm in aerodynamic (PM10; RR: 1.040, 95 % CI: 0.996-1.087), PM2.5 (1.025, 1.004-1.045), nitrogen dioxide (NO2; 1.074, 1.039-1.111), and sulfur dioxide (SO2; 1.079, 1.019-1.141) at Lag 0 and ozone (O3; 1.018, 1.004-1.031) at Lag 4. In cumulative lag day structures, the highest RRs were 1.225 (1.079,1.392) for PM10 at Lag 06, 1.054 (1.013, 1.098) for PM2.5 at Lag 03, 1.200 (1.119, 1.287) for NO2 at Lag 04, and 1.135 (1.025, 1.257) for SO2 at Lag 02. Moreover, the association between air pollution and CVD risk was modified by sex and age (P < 0.05). Females and individuals aged ≤65 years were more vulnerable to NO2 and had a higher CVD risk.

CONCLUSION

Short-term exposure to air pollution was positively associated with CVD risk. Moreover, sex and age could modify the effect of air pollution on CVD risk. Females and individuals aged ≤65 years had a higher NO2 exposure-induced CVD risk.

Per- and polyfluoroalkyl substances, polychlorinated biphenyls, organochlorine pesticides, and polybrominated diphenyl ethers and dysregulation of MicroRNA expression in humans and animals-A systematic review

BACKGROUND

Persistent organic pollutants (POPs) are chemicals characterized by their environmental persistence. Evidence suggests that exposure to POPs, which is ubiquitous, is associated with microRNA (miRNA) dysregulation. miRNA are key regulators in many physiological processes. It is thus of public health concern to understand the relationships between POPs and miRNA as related to health outcomes.

OBJECTIVES

This systematic review evaluated the relationship between widely recognized, intentionally manufactured, POPs, including per- and polyfluoroalkyl substances (PFAS), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides (dichlorodiphenyltrichloroethane [DDT], dichlorodiphenyldichloroethylene [DDE], hexachlorobenzene [HCB]), with miRNA expression in both human and animal studies.

METHODS

We used PubMed and Embase to systematically search the literature up to September 29th, 2023. Search results for human and animal studies were included if they incorporated at least one POP of interest in relation to at least one miRNA. Data were synthesized to determine the direction and significance of associations between POPs and miRNA. We utilized ingenuity pathway analysis to review disease pathways for miRNA that were associated with POPs.

RESULTS

Our search identified 38 eligible studies: 9 in humans and 29 in model organisms. PFAS were associated with decreased expression of miR-19, miR-193b, and miR-92b, as well as increased expression of miR-128, miR-199a-3p, and miR-26b across species. PCBs were associated with increased expression of miR-15a, miR-1537, miR-21, miR-22-3p, miR-223, miR-30b, and miR-34a, as well as decreased expression of miR-130a and let-7b in both humans and animals. Pathway analysis for POP-associated miRNA identified pathways related to carcinogenesis.

DISCUSSION

This is the first systematic review of the association of POPs with miRNA in humans and model organisms. Large-scale prospective human studies are warranted to examine the role of miRNA as mediators between POPs and health outcomes.

Circulatory health risks from additive multi-pollutant models: short-term exposure to three common air pollutants in Canada

Numerous studies have reported adverse health effects of ambient air pollution on circulatory health outcomes mainly based on single-pollutant models. However, limited studies have focused on adjusted effect of multi-pollutant exposures on public health. This study aimed to examine short-term effects of three common air pollutants-ground-level ozone (ozone), nitrogen dioxide (NO2), and fine particulate matter (PM2.5)-through multi-pollutant models for mixed effect of adjustment. Daily data (circulatory hospitalization and mortality) and hourly data (air pollutants and temperature) were collected for 24 Canadian cities for 2001-2012. We applied generalized additive over-dispersion Poisson regression models with 1, 2, or 3 pollutants for city-specific risks, and Bayesian hierarchical models for national risks. This study found little mixed effect of adjustment through multi-pollutant models (ozone and/or NO2 and/or PM2.5) for circulatory hospitalization or mortality in Canada for 2001-2012, indicating that the 1-pollutant model did not result in considerable under- or over-estimates. It seemed weak-to-moderate correlations among air pollutants did not change the significant effect of one air pollutant after accounting for others. Inconsistent findings between other previous studies and this study indicate the need of comparable study design for multi-pollutant effect analysis.

State of gaseous air pollutants and resulting health effects in Karachi, Pakistan

Karachi, Pakistan, is a priority site for air pollution research due to high emissions of air pollutants from vehicular traffic, industrial activities, and biomass burning, as well as rapid growth in population. The objectives of this study were to investigate the levels of gaseous pollutants (NO, NO₂, O₃, HNO₃, and SO₂) in Karachi, to determine temporal and seasonal variations, to compare Karachi's air quality with other urban centers, to identify relationships with meteorological conditions, to identify source characterization, and to perform a backward-in-time trajectory analysis and a health impact assessment. Daily samples of gaseous pollutants were collected for six consecutive weeks in each of the four seasons for a year. Daily maximum concentrations of NO (90 parts per billion by volume (ppbv)), NO₂ (28.1 ppbv), O₃ (57.8 ppbv), and SO₂ (331 ppbv) were recorded in fall, while HNO₃ (9129 parts per trillion by volume (pptv)) was recorded in spring. Seasonal average concentrations were high in winter for NO (9.47 ± 7.82 ppbv), NO₂ (4.84 ± 3.35 ppbv), and O₃ (8.92 ± 7.65 ppbv), while HNO₃ (629 ± 1316 pptv) and SO₂ (20.2 ± 39.4 ppbv) were high in spring and fall, respectively. The observed SO₂ seasonal average concentration in fall (20.2 ± 39.4) was 5 times higher than that in summer (3.97 ± 2.77) with the fall 24-h average (120 ppbv) exceeding the WHO daily guideline (7.64 ppbv) by a factor of about 15.7. A health impact assessment estimated an increase of 1200 and 569 deaths due to short-term exposure to SO₂ in fall and spring, respectively. Chronic daily intake estimated risk per 1000 was 0.99, 0.47, 0.45, and 0.26 for SO₂ in fall, NO in winter, O₃ in winter, and NO₂ in spring, respectively. This study confirms the effect of poor urban air quality on public health and demonstrated the influence of photochemical reactions as well as unfavorable meteorological conditions on the formation of secondary pollutants.

Ambient NO2 exposure induces migraine in rats: Evidence, mechanisms and interventions

Migraine is a complex neurological disorder with a high disability rate. Although the precipitating factors of migraine remain unclear, previous studies suggest that when there is excess nitrogen dioxide (NO₂) pollution in the atmosphere, the medical demand due to migraine attacks increases sharply. However, the main role of NO₂ as a trigger for migraine is not yet well understood. The purpose of this study was to explore the relationship between NO₂ exposure and the occurrence of migraine as well as the possible underlying mechanisms. We first investigated whether repeated short-term NO₂ exposure could induce behavioural and biological migraine phenotypes in rats. Next, capsazepine (CZP) was used to block transient receptor potential cation channel subfamily V member 1 (TRPV1) in vivo, and CZP and vitamin E (VE) were used to verify the role of reactive oxygen species (ROS)-TRPV1 signalling in NO₂-induced migraine in primary trigeminal neurones in vitro. We demonstrated that short-term repeated NO₂ exposure can significantly induce migraine in rats, and its key molecular mechanism may be related to ROS burst and its downstream TRPV1 channel activation. The findings of this study will enhance the understanding of the neurotoxic mechanism of NO₂, provide new clues for identifying the aetiology of migraine, and lay a new experimental basis for implementing migraine-related preventive and therapeutic control measures.

Ambient air pollutants and respiratory health outcomes in Tabriz and Urmia, two metropolises of Iran

Polluted air affects human life and it is crucial to assess air pollutants to inform policy and protect human lives. In this study, we sought to assess the respiratory outcomes associated with PM₁₀, O₃, SO₂, and NO₂ in the Iranian population. The required data, which included concentrations of air pollutants, meteorology, and population size, were obtained from the department of environment and meteorological organizations. The validity of the data was evaluated, and appropriate calculations were conducted on the data to extract the required values and parameters for modeling (using the AirQ2.2.3). This study was conducted in two megacities of Iran (Tabriz and Urmia) with over 2 million population. The annual averages of SO₂, NO₂, and PM₁₀ concentrations were 9, 73, and 43 μg/m³ in Tabriz and 76, 29, and 76 μg/m³ in Urmia, respectively. Excess deaths from respiratory diseases associated with PM₁₀ and SO₂ were estimated to be 33.1 and 1.2 cases in Tabriz and 31.6 and 24.7 cases in Urmia, respectively. The proportions of hospitalizations for chronic obstructive pulmonary disease (COPD) attributable to SO₂ and NO₂ in Tabriz were 0.07% and 1.61%, respectively, whereas they were 2.84% and 0.48% in Urmia. O₃ had an annual average of 56 μg/m³ in Tabriz and with 44.5 excess respiratory deaths and 42.5 excess hospital admissions for COPD, it had the greatest health impacts among the pollutants studied. Findings from this study add to the growing literature, especially from developing countries, that provides insights to help authorities and decision-makers develop and implement effective interventions to curb air pollution and save lives.

Short term exposure to ambient air pollutants and cardiovascular emergency department visits in Mexico city

Available data on the acute cardiovascular effect of ambient air pollution (AAP) in Latin America is limited considering that over 80% of its 1 billion inhabitants live in urban settlements with poor air quality. The study aim was to evaluate the association between Cardiovascular Emergency Department Visits (CEDVs) and AAP in Mexico City from 2016 to 2019 using generalized additive models with distributed lags to examine the percentage change of CEDVs and a backward approach of time-series model to calculate attributable fractions. A total of 48,891 CEDVs were recorded in a period of 1019 days. We estimated a significant percentage increase for each 10 μg/m³ of PM₁₀ at Lag0-5 (2.8%, 95%CI 0.6-5.0), PM_2.5 at Lag0-6 (3.7%, 95%CI 0.1-7.6), O₃ at Lag0-5 (1.1%, 95%CI 0.2-2.0), NO₂ at Lag0-4 (2.5%, 95%CI 0.3-4.7) and for each 1 mg/m³ of CO at Lag0 (6.6%, 95%CI 0.3-13.2). Overall, 10.3% of CEDVs in Mexico City may be related to PM¹⁰ exposure, 9.5% to PM_2.5, 10.3% to O₃, 11% to NO₂ and 5.7% to CO. AAP significantly increase cardiovascular morbidity impacting on emergency medical services.

Ambient sulfur dioxide and hospital expenditures and length of hospital stay for respiratory diseases: A multicity study in China

BACKGROUND

Ambient sulfur dioxide (SO2) has been associated with morbidity and mortality of respiratory diseases, however, its effect on length of hospital stays (LOS) and cost for these diagnoses remain unclear.

METHODS

We collected hospital admission information for respiratory diseases from all 11 cities in the Shanxi Province of China during 2017-2019. We assessed individual-level exposure by using an inverse distance weighting approach based on geocoded residential addresses. A generalized additive model was built to delineate city-specific effects of SO2 on hospitalization, hospital expenditure, and length of hospital stay for respiratory diseases. The overall effects were obtained by random-effects meta-analysis. We further estimated the respiratory burden attributable to SO2 by comparing different reference concentrations.

RESULTS

We observed significant effects of SO2 exposure on respiratory diseases. At the provincial level, each 10 μg/m3 increase in SO2 on lag03 was associated with a 0.63% (95% CI: 0.14-0.11) increase in hospital admission, an increase of 4.56 days (95% CI: 1.16-7.95) of hospital stay, and 3647.97 renminbi (RMB, Chinese money) (95% CI: 1091.05-6204.90) in hospital cost. We estimated about 6.13 (95% CI: 1.33-11.10) thousand hospital admissions, 65.77 million RMB (95% CI: 19.67-111.87) in hospital expenditure, and 82.13 (95% CI: 20.87-143.40) thousand days of hospital stay could have potentially been avoided had the daily SO2 concentrations been reduced to WHO's reference concentration (40 µg/m3). Variable values in correspondence with this reference concentration could reduce the hospital cost and LOS of each case by 52.67 RMB (95% CI: 15.75-89.59) and 0.07 days (95% CI: 0.02-0.117).

CONCLUSION

This study provides evidence that short-term ambient SO2 exposure is an important risk factor of respiratory diseases, indicating that continually tightening policies to reduce SO2 levels could effectively reduce respiratory disease burden in Shanxi Province.

Impact of ambient fine particulate matter on emergency department admissions for circulatory system disease in a city in Northeast China

The cardiovascular impact of fine particles has caused great concern worldwide. However, evidences on the impact of fine particulate matter (PM_2.5) on emergency department (ED) admissions for circulatory system disease in Northeast China is limited. We assessed the acute, lag, cumulative, and harvesting effects of PM_2.5 on ED admissions for circulatory system diseases and their exposure-response relationship. A total of 26,168 ED admissions, including those for hypertension, ischemic heart disease (IHD), arrhythmia, heart failure (HF), and cerebrovascular events (CVE), were collected from the Shenyang Emergency Center from 1 January 2017 to 31 December 2018. The relationship between PM_2.5 and ED admissions for circulatory system disease was estimated using a distributed lag non-linear model and a generalized additive quasi-Poisson model. We stratified the analyses by temperature. Air pollution was positively correlated with daily ED admissions for circulatory system disease or other cause-specific diseases under different lag structures. For every 10-μg/m³ increase in the PM_2.5 concentration, the relative risk of daily ED admissions for circulatory system disease was 1.007 [95% confidence interval (CI), 1.001-1.013] in lag0, 1.007 (95%CI, 1.000-1.013) in lag1, and 1.011 (95%CI, 1.002-1.021) in lag03. A lag effect was found in IHD, a cumulative effect was found in CVE, and both lag and cumulative effects were found in hypertension and arrhythmia. A harvesting effect was observed in daily ED admissions for circulatory system disease and HF. We found no interaction between pollutants and temperature. We observed a monotonic and almost linear exposure-response relationship between PM_2.5 and circulatory system disease with no threshold effect.PM_2.5 contributes to obvious acute, lag, cumulative, and harvesting effects on circulatory system disease. PM_2.5 was associated with the risk of daily ED admissions for circulatory system disease, hypertension, IHD, arrhythmia, HF, and CVE. Therefore, air quality management must be strengthened.

Significance between air pollutants, meteorological factors, and COVID-19 infections: probable evidences in India

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease represents the causative agent with a potentially fatal risk which is having great global human health concern. Earlier studies suggested that air pollutants and meteorological factors were considered as the risk factors for acute respiratory infection, which carries harmful pathogens and affects the immunity. The study intended to explore the correlation between air pollutants, meteorological factors, and the daily reported infected cases caused by novel coronavirus in India. The daily positive infected cases, concentrations of air pollutants, and meteorological factors in 288 districts were collected from January 30, 2020, to April 23, 2020, in India. Spearman's correlation and generalized additive model (GAM) were applied to investigate the correlations of four air pollutants (PM2.5, PM10, NO2, and SO2) and eight meteorological factors (Temp, DTR, RH, AH, AP, RF, WS, and WD) with COVID-19-infected cases. The study indicated that a 10 μg/m3 increase during (Lag0-14) in PM2.5, PM10, and NO2 resulted in 2.21% (95%CI: 1.13 to 3.29), 2.67% (95% CI: 0.33 to 5.01), and 4.56 (95% CI: 2.22 to 6.90) increase in daily counts of Coronavirus Disease 2019 (COVID 19)-infected cases respectively. However, only 1 unit increase in meteorological factor levels in case of daily mean temperature and DTR during (Lag0-14) associated with 3.78% (95%CI: 1.81 to 5.75) and 1.82% (95% CI: -1.74 to 5.38) rise of COVID-19-infected cases respectively. In addition, SO2 and relative humidity were negatively associated with COVID-19-infected cases at Lag0-14 with decrease of 7.23% (95% CI: -10.99 to -3.47) and 1.11% (95% CI: -3.45 to 1.23) for SO2 and for relative humidity respectively. The study recommended that there are significant correlations between air pollutants and meteorological factors with COVID-19-infected cases, which substantially explain the effect of national lockdown and suggested positive implications for control and prevention of the spread of SARS-CoV-2 disease.

Association between atmospheric PM2.5 and daily outpatient visits for children's respiratory diseases in Lanzhou

The relationship between fine particulate matter (PM_2.5) and respiratory disease outcomes among children aged 0 to 14 years in Lanzhou, China, was evaluated. We utilized a generalized additive model linked by a quasi-Poisson distribution to examine the associations between PM_2.5 and paediatric respiratory outpatient visits for time lags of 0 up to 7 days, and stratified by gender, age, and season. Cases of respiratory disease in children were collected from 3 large hospitals for the years 2014-2017 and then linked with air pollutant concentrations from 4 air quality monitoring stations by date. We observed positive and significant associations between PM_2.5 and respiratory disease from the lag to lag 7, and from lag01 to lag07, with ER reaching the maximum value at lag07. For each 10 μg/m³ increase in PM_2.5 (lag07), the associated increment in respiratory diseases was 2.83% (95% CI 1.80%-3.86%). Males were more sensitive to the adverse effects, and the association was more significant in spring (from March to May) and winter (from December to the next February). Overall, the child group (age 3-6 years) demonstrated a higher risk of respiratory disease after PM_2.5 exposure. The associations between ambient PM_2.5 and respiratory hospital outpatients among young children became partially attenuated after the adjustment for gaseous pollutants in subgroups. The exposure-response curves were positive and generally nonlinear but flatted at concentrations over 60 μg/m³. This research found a significant association between ambient PM_2.5 levels and hospital outpatient visits in child with respiratory diseases in Lanzhou, China.

Air quality modeling to inform pollution mitigation strategies in a Latin American megacity

Poor air quality disproportionally impacts cities in low- and middle-income countries. In Bogotá, Colombia, a metropolitan area with over 10 million inhabitants, fine particulate matter (PM_2.5) levels regularly exceed air quality guidelines, leading to detrimental effects on health. Although there is public interest to improve the city's air quality, the main sources of PM_2.5 pollution have not been clearly identified and the use of modeling for policy development in Bogotá has been limited. Here, we apply a modeling framework based on the Community Multiscale Air Quality Modeling System (CMAQ) to conduct seasonal simulations of air pollution in Bogotá and reveal the emissions sectors with the largest contributions to PM_2.5. Based on these results, we project and compare the air quality benefits of potential pollution mitigation strategies focused on these sources. The analysis finds that resuspended dust from unpaved roads is the largest local source of PM_2.5 and can contribute over 30% of seasonally-averaged concentration across the city. Vehicles, industrial activity, and unpaved road dust combined are responsible for over 60% of PM_2.5 pollution in Bogotá. A scenario analysis shows that paving roads can lead to PM_2.5 decreases of nearly 10 μg/m³ by 2030 in some areas of the city, but air quality will deteriorate significantly over others in the absence of additional emissions control measures. Mitigation strategies designed to target the sectors with the largest contributions to PM_2.5, including road cleaning systems, controls for industrial point sources, cleaner transportation fuels, and updated vehicle fleets, can largely avert projected increases in concentrations, although the impacts of different approaches vary throughout the city. This study is the first to use a comprehensive model to determine sector contributions to air pollution and inform potential emissions control policies in Bogotá, demonstrating an approach to guide pollution management in developing cities facing comparable challenges.

The construction of the air quality health index (AQHI) and a validity comparison based on three different methods

The most common currently used air quality risk communication tool, the Air Quality Index (AQI), has been criticized. As a result, Canada proposed the Air Quality Health Index (AQHI) to communicate the health risks of multiple pollutants. However, the AQHI is calculated by directly summing the excess risks from single-pollutant models, which may overestimate the effects of the pollutants. To solve this problem, we introduced two methods for estimating the joint effects of multiple pollutants: the cumulative risk index (CRI) and supervised principal component analysis (SPCA). Based on three methods, i.e., the standard, CRI and SPCA methods, we constructed three types of AQHIs and compared their validity to select the best communication tool. Our results showed that compared with the AQI, all three AQHIs had a linear relationship with mortality. In addition, the CRI-AQHI had the best goodness of fit and captured the overall health risk of pollution mixtures most robustly among various cause-specific mortalities when identifying health risks. Our study indicated that the CRI-AQHI may have the potential to be a better alternative to the standard AQHI in communicating air pollution-related health risks to the public.

Associations between ambient air pollution and medical care visits for atopic dermatitis

BACKGROUND

Previous studies have reported numerous environmental factors for atopic dermatitis (AD), such as allergens and chemical stimulants. However, few studies have addressed the relationship between ambient air pollution and AD at a population level.

OBJECTIVE

To evaluate the effect of air pollutants on medical care visits for AD and to identify susceptible populations.

METHODS

In this time-series study conducted on 513,870 medical care visits for AD from 2012 to 2015 identified by reviewing national health insurance claim data in Incheon, Republic of Korea. Treating daily number of medical care visits for AD as a dependent variable, generalized additive models with Poisson distributions were constructed, which included air pollutant levels, ambient temperature, relative humidity, day of the week, national holiday, and season. Risks were expressed as relative risks (RR) with 95% confidence intervals (95% CIs) per interquartile range increase of each air pollutant.

RESULTS

Higher levels of particulate matter of diameter ≤10 μm (PM₁₀) (RR, 1.009; 95% CI, 1.007-1.012), ozone (1.028; 1.023-1.033), and sulfur dioxide (1.033; 1.030-1.037) were significantly associated with increased risk of medical care visits for AD on same days. In all age and sex groups, ozone was associated with a significantly higher risk of medical care visits, with the greatest risk among 13- to 18-year-old males (RR, 1.127; 95% CI, 1.095-1.159).

CONCLUSION

This study suggests relationships of ambient PM₁₀, ozone, and sulfur dioxide levels with medical care visits for AD.

Air pollution, sociodemographic and health conditions effects on COVID-19 mortality in Colombia: An ecological study

OBJECTIVE

The present study aimed to determine the association between chronic exposure to fine particulate matter (PM2.5), sociodemographic aspects, and health conditions with COVID-19 mortality in Colombia.

METHODS

We performed an ecological study using data at the municipality level. We used COVID-19 data obtained from government public reports up to and including July 17th, 2020. We defined PM2.5 long-term exposure as the 2014-2018 average of the estimated concentrations at municipalities obtained from the Copernicus Atmospheric Monitoring Service Reanalysis (CAMSRA) model. We fitted a logit-negative binomial hurdle model for the mortality rate adjusting for sociodemographic and health conditions.

RESULTS

Estimated mortality rate ratios (MRR) for long-term average PM2.5 were not statistically significant in either of the two components of the hurdle model (i.e., the likelihood of reporting at least one death or the count of fatal cases). We found that having 10% or more of the population over 65 years of age (MRR = 3.91 95%CI 2.24-6.81), the poverty index (MRR = 1.03 95%CI 1.01-1.05), and the prevalence of hypertension over 6% (MRR = 1.32 95%CI1.03-1.68) are the main factors associated with death rate at the municipality level. Having higher hospital beds capacity is inversely correlated to mortality.

CONCLUSIONS

There was no evidence of an association between long-term exposure to PM2.5 and COVID-19 mortality rate at the municipality level in Colombia. Demographics, health system capacity, and social conditions did have evidence of an ecological effect on COVID-19 mortality. The use of model-based estimations of long-term PM2.5 exposure includes an undetermined level of uncertainty in the results, and therefore they should be interpreted as preliminary evidence.

Public Health Considerations for PM10 in a High-Pollution Megacity: Influences of Atmospheric Condition and Land Coverage

This paper analyzes the PM10 concentrations and influences of atmospheric condition (AC) and land coverage (LC) on a high-pollution megacity (Bogota, Colombia) from a public health viewpoint. Information of monitoring stations equipped with measuring devices for PM10/temperature/solar-radiation/wind-speed were used. The research period lasted eight years (2007–2014). AC and LC were determined after comparing daily PM10 concentrations (DPM10) to reference limits published by the World Health Organization (WHO). ARIMA models for DPM10 were also developed. The results indicated that urban sectors with lower atmospheric instability (AI) had a 2.85% increase in daily mortality (DM) in relation to sectors with greater AI. In these sectors of lower AI, impervious LC predominated, instead of vegetated LC. An ARIMA analysis revealed that a greater extent of impervious LC around a station led to a greater effect on previous days’ DPM10 concentrations. Extreme PM10 episodes persisted for up to two days. Extreme pollution episodes were probably also preceded by low mixing-layer heights (between 722–1085 m). The findings showed a 13.0% increase in WHO standard excesses (PE) for each 10 µg/m3 increase in DPM10, and a 0.313% increase in DM for each 10% increase in PE. The observed average reduction of 14.8% in DPM10 (−0.79% in DM) was probably due to 40% restriction of the traffic at peak hours.

Assessment of personal exposure to particulate air pollution in different microenvironments and traveling by several modes of transportation in Bogotá, Colombia: protocol for a mixed-methods study. (Preprint)

Background

Air pollution in most countries exceeds the levels recommended by the World Health Organization, causing up to one-third of deaths due to noncommunicable diseases. Fine particulate matter (PM_2.5) and black carbon (BC) from mobile sources are the main contaminants.

Objective

The aim of this study is to assess the relationship of exposure to air pollutants (PM_2.5 and BC) in microenvironments according to respiratory health and physical activity in users traveling by different types of transportation in Bogotá, Colombia.

Methods

A mixed methods study based on a convergent parallel design will be performed with workers and students. The sample will include 350 healthy transport users traveling by different urban transportation modes in three main routes in Bogotá. The study is broken down into two components: (1) a descriptive qualitative component focused on assessing the individual perception of air pollution using semistructured interviews; and (2) a cross-sectional study measuring the individual exposure to PM_2.5 and BC using portable instruments (DustTrak and microAeth, respectively), pulmonary function by spirometry, and physical activity with accelerometry. The analysis will include concurrent triangulation and logistic regression.

Results

The findings will be useful for the conception, design, and decision-making process in the sectors of health and mobility from public, academy, and private perspectives. This study includes personal measurements of PM_2.5 and BC during typical trips in the city to assess the exposure to these contaminants in the major roadways in real time. The study further compares the performance of two different lung tests to identify possible short-term respiratory effects. As a limitation, the protocol will include participants from different institutions in the city, which are not necessarily representative of all healthy populations in Bogotá. In this sense, it is not possible to draw causation conclusions. Moreover, a convergent parallel design could be especially problematic concerning integration because such a design often lacks a clear plan for making a connection between the two sets of results, which may not be well connected. Nevertheless, this study adopts a procedure for how to integrate qualitative and quantitative data in the interpretation of the results and a multilevel regression. The time that participants must live in the city will be considered; this will be controlled in the stratified analysis. Another limitation is the wide age range and working status of the participants. Regional pollution levels and episodes (PM_2.5) will be handled as confounding variables. The study is currently in the enrollment phase of the participants. Measurements have been made on 300 participants. Pandemic conditions affected the study schedule; however, the results are likely to be obtained by late 2022.

Conclusions

This study investigates the exposure to air pollutants in microenvironments in Bogotá, Colombia. To our knowledge, this is the first mixed methods study focusing on PM_2.5, BC, and respiratory health effects in a city over 2 meters above sea level. This study will provide an integration of air pollution exposure variables and respiratory health effects in different microenvironments.

International Registered Report Identifier (IRRID)

PRR1-10.2196/25690

Quantification of mortality and morbidity attributed to the ambient air criteria pollutants in Shiraz city, Iran

According to the epidemiological surveys, ambient air pollution has directly related to mortality and different diseases such as cardiovascular and respiratory defects. Among the atmospheric contaminants, criteria air ones (NO₂, O₃, PM_2.5/10, SO₂) demonstrated that have particular importance in the community disease. The overall goal of this paper was to study the impact of criteria air contaminants on the health of the inhabitants of Shiraz city, Iran. To accomplish this, the AirQ_2.2.3 software was applied. The results of the study revealed that the annual average NO₂, SO₂, PM_2.5, PM_10, and O₃ concentrations are 39.98, 27.6, 14.35, 46.16, and 120.03 μg/m³ in 2016 and 30.27, 23.97, 16.45, 51.65, and 52.58 μg/m³ in 2017. The total International Classification of Diseases (ICD), cardiovascular, and respiratory mortalities caused by air contaminants in Shiraz was predicted as 911, 628, and 182 cases in 2016, and 346, 370, and 82 cases in 2017, respectively. Sulfur dioxide (SO₂) had the greatest rate of total mortality with the attributable equivalent of 4.3% in 2016, but this value has been decreased to 0.42% in 2017. The findings of this research revealed that air contamination has caused problems in Shiraz city according to the predicted results. The findings of this work provide useful data for regional and national health policymakers, who should take decisions to develop strategies for control air contaminants and estimate the cost-effectiveness of interventions.

A spatial analysis of childhood cancer and industrial air pollution in a metropolitan area of Colombia

BACKGROUND

Air pollutants are considered carcinogenic to humans. In some European countries, an association between industrial air pollution and childhood cancer has been established. This relationship has not been addressed in Latin America, despite the spatial variability of air pollutants that may limit the extrapolation of the results to other geographical areas.

OBJECTIVE

To conduct a spatial analysis of the relationship between childhood cancer and proximity to industrial sources of air pollution in a metropolitan area of Colombia.

METHODS

Incident cases of childhood cancers were obtained from the Population-based Cancer Registry of the Metropolitan Area of Bucaramanga during 2000-2015. Local and focused cluster tests were used for the detection of spatial clusters, and the Poisson multivariable model was used to evaluate the combined effects of spatial variables.

RESULTS

The Kulldorff's focused test found a significant spatial cluster (P < 0.001) around one industrial agglomerate and the multivariable model results suggests that the distance effect is modified by the directional effect of the wind.

CONCLUSION

A spatial cluster of incident cases of childhood cancer occurred in the municipality of Bucaramanga, Colombia. Our finding supports the hypothesis that childhood cancer might be related with industrial air pollution exposure in a Latin American city.

Análisis espacial de las concentraciones de PM2,5 en Bogotá según los valores de las guías de la calidad del aire de la Organización Mundial de la Salud para enfermedades cardiopulmonares, 2014-2015

Introducción.

La Organización Mundial de la Salud señala que tres millones de muertes al año por enfermedades cardiopulmonares están relacionadas con la exposición a la contaminación del aire.

Objetivo.

Estimar las superficies de concentración de partículas en suspensión de menos de 2,5 pm (Particulate Matter, PM₂₅) en Bogotá entre el 2014 y el 2015, clasificándolas según las guías de calidad del aire de la Organización Mundial de la Salud para enfermedades cardiopulmonares.

Materiales y métodos.

Se hizo un estudio ecológico mediante técnicas geoestadísticas. Se calcularon los promedios de PM₂₅ en lapsos de seis horas a lo largo del día en cuatro franjas horarias. Las concentraciones se clasificaron según los valores diarios y anuales de las guías de calidad del aire de la OMS.

Resultados.

La localidad de Kennedy presentó las mayores concentraciones de PM₂₅ en todas las franjas horarias. Los valores registrados en esta zona y clasificados según las guías diarias y anuales de calidad del aire, evidenciaron que la localidad presentaría un incremento de 1,2 % en la mortalidad cardiopulmonar en el corto plazo y de 9 % en el largo plazo.

Conclusión.

Las franjas horarias de las 0:00 a las 6:00 h y de las 12:00 a las 18:00 h, cumplieron con el valor anual de las guías de calidad del aire de 10 µg/m³ en una parte de la zona oriental de la ciudad. En el resto de la ciudad, en las franjas horarias de las 6:00 h a las 12:00 h y de las 18:00 h a las 24:00 h se registraron valores que cumplían los objetivos intermedios 2 y 3, lo que representa incrementos de 9 y 3 % en la mortalidad cardiopulmonar, respectivamente.

Joint effect of multiple air pollutants on daily emergency department visits in Chengdu, China

Existing studies have typically investigated only the association between single pollutants and health outcomes. However, in the real world, people are exposed to multiple air pollutants simultaneously. The effect of air pollutants on emergency department (ED) visits has not been previously studied in the Sichuan Basin, which is one of the most polluted areas. We collected nonaccidental, respiratory and cardiovascular daily ED visits and daily concentrations of PM_2.5, PM_c, CO, SO₂, NO₂ and O₃ in Chengdu, China, from 2014 to 2016. A weighted variable for the combination of multiple air pollutants was constructed to assess the joint adverse health effects. Each air pollutant was assigned a health-related weight, which indicated the pollutant's relative contribution to the joint effect. The effects on specific subpopulations (males and females; 15-65 years old and >65 years old) were also examined. With an increase of 10 μg/m³ of the combined multiple air pollutants, the daily ED visits for nonaccidental, respiratory and cardiovascular causes increased by 0.96% (95% CI: 0.51%-1.39%), 1.19% (95% CI: 0.53%, 1.85%) and 4.36% (95% CI: 1.06%, 7.76%) at lag 1, respectively. Males presented more pronounced effects, except for cardiovascular disease, than females. Elderly individuals were found to be more sensitive than young individuals. For nonaccidental and respiratory diseases, the contributions of particulate matter (PM) were dominant among the air pollutants, whereas cardiovascular disease was mainly affected by gaseous air pollutants. The combination of multiple air pollutants was significantly associated with ED visits in the Sichuan Basin, China. The joint effect of the combination of multiple air pollutants was highest for cardiovascular disease at lag 1. The relative contributions of individual pollutants varied by disease and subpopulation. These findings suggest that under different pollution scenarios, preventive strategies should target those with different diseases and different subpopulations.

Monthly-Term Associations Between Air Pollutants and Respiratory Morbidity in South Brazil 2013-2016: A Multi-City, Time-Series Analysis

Most air pollution research conducted in Brazil has focused on assessing the daily-term effects of pollutants, but little is known about the health effects of air pollutants at an intermediate time term. The objective of this study was to determine the monthly-term association between air pollution and respiratory morbidity in five cities in South Brazil. An ecological time-series study was performed using the municipality as the unit of observation in five cities in South Brazil (Gravataí, Triunfo, Esteio, Canoas, and Charqueadas) between 2013 and 2016. Data for hospital admissions was obtained from the records of the Hospital Information Service. Air pollution data, including PM₁₀, SO₂, CO, NO₂, and O₃ (µg/m³) were obtained from the environmental government agency in Rio Grande do Sul State. Panel multivariable Poisson regression models were adjusted for monthly counts of respiratory hospitalizations. An increase of 10 μg/m³ in the monthly average concentration of PM₁₀ was associated with an increase of respiratory hospitalizations in all age groups, with the maximum effect on the population aged between 16 and 59 years (IRR: Incidence rate ratio 2.04 (95% CI: Confidence interval = 1.97–2.12)). For NO₂ and SO₂, stronger intermediate-term effects were found in children aged between 6 and 15 years, while for O₃ higher effects were found in children under 1 year. This is the first multi-city study conducted in South Brazil to account for intermediate-term effects of air pollutants on respiratory health.