Indoor PM2.5, tobacco smoking and chronic lung diseases: A narrative review

Exploring the Cellular Impact of Size-Segregated Cigarette Aerosols: Insights into Indoor Particulate Matter Toxicity and Potential Therapeutic Interventions

Exposure to anthropogenic aerosols has been associated with a variety of adverse health effects, increased morbidity, and premature death. Although cigarette smoke poses one of the most significant public health threats, the cellular toxicity of particulate matter contained in cigarette smoke has not been systematically interrogated in a size-segregated manner. In this study, we employed a refined particle size classification to collect cigarette aerosols, enabling a comprehensive assessment and comparison of the impacts exerted by cigarette aerosol extract (CAE) on SH-SY5Y, HEK293T, and A549 cells. Exposure to CAE reduced cell viability in a dose-dependent manner, with organic components having a greater impact and SH-SY5Y cells displaying lower tolerance compared to HEK293T and A549 cells. Moreover, CAE was found to cause increased oxidative stress, mitochondrial dysfunction, and increased levels of apoptosis, pyroptosis, and autophagy, leading to increased cell death. Furthermore, we found that rutin, a phytocompound with antioxidant potential, could reduce intracellular reactive oxygen species and protect against CAE-triggered cell death. These findings underscore the therapeutic potential of antioxidant drugs in mitigating the adverse effects of cigarette aerosol exposure for better public health outcomes.

Assessing Causality Between Second-Hand Smoking and Potentially Associated Diseases in Multiple Systems: A Two-Sample Mendelian Randomization Study

INTRODUCTION

The global disease burden may be exacerbated by exposure to passive smoking (SHS), with the workplace being a primary location for such exposure. Numerous epidemiological studies have identified SHS as a risk factor for diseases affecting various systems, including cardiovascular, respiratory, immune, endocrine, and nervous systems. The conventional observational study has certain methodological constraints that can be circumvented through a Mendelian randomization (MR) study. Our MR study intends to investigate the causal link between workplace exposure to SHS and the potential associated diseases.

AIM AND METHODS

Summary statistics data involving European participants were sourced from three databases: the UK Biobank, the FinnGen study, and the European Bioinformatics Institute. Genetic variants linked with exposure to SHS in the workplace were identified as instrumental variables. The MR was carried out using inverse variance weighted (IVW), MR-Egger, and weighted median methods. Sensitivity tests were also undertaken within the MR to evaluate the validity of the causality.

RESULTS

According to the IVW model, genetically determined atrial fibrillation (AF) and stroke (p = 6.64E-04 and 5.68E-07, odds ratio = 2.030 and 2.494, 95% confidence interval = 1.350 to 3.051 and 1.743 to 3.569) were robustly associated with exposure to SHS in the workplace. Suggestive associations were found between workplace SHS and myocardial infarction (MI), asthma, and depression.

CONCLUSIONS

The MR study demonstrates that exposure to SHS in the workplace is a significant risk factor for AF and stroke in European individuals. Whether workplace exposure to SHS influences other diseases and the causality between them requires further exploration.

IMPLICATIONS

This study explored the causality between exposure to SHS in the workplace and potential associated diseases in multiple systems, including MI, AF, stroke, lung cancer, asthma, allergic disease, type 2 diabetes, and depression, using an MR study. The MR study can circumvent the methodological constraints of observational studies and establish a causal relationship. The two-sample MR analysis provides evidence supporting the causal association of frequent workplace SHS with AF and stroke. Individuals exposed to SHS in the workplace may also have a heightened risk of MI, asthma, and depression. However, whether SHS affects other diseases and the causality between them requires further investigation. To our knowledge, this is the first two-sample MR study to determine the causal relationship between SHS and potential diseases. Exposure to SHS in the workplace is a prevalent issue and may contribute to a global disease burden. The reduction of exposure following the introduction of smoke-free laws has led to a decrease in the admission rate for cardiac events and an improvement in health indicators. It is crucial to further advance smoke-free policies and their implementation.

Exposure to airborne particulate matter in working from office and working from home employees

The main aim of this study is to quantitatively evaluate the differences, in terms of exposure to PM (particulate matter), between WFO (working-from-office) and WFH (working-from-home) conditions. Two measurement surveys were performed: a long-term and a short-term campaign, focused on the monitoring of personal exposure to size-fractionated PM in these different working conditions. Results of the long-term campaign show that the WFH subject is exposed to higher (up to 4 times) PM concentration, compared to the WFO subject. Specific activities performed by the subjects impacted their exposure concentrations, even if the most relevant contribution to total exposure was made by desk work. Results of the short-term campaign indicate that the subjects can be divided into two groups: subjects most exposed during the WFH mode (HE_H - Higher_Exposure_Home) and subjects most exposed during the WFO mode (HE_O - Higher_Exposure_Office). HE_H group is exposed to levels of pollutants up to 4 times higher in the domestic than in the office environment, during the moment of desk work. The HE_O group is exposed to higher (double) concentration levels during desk work during the WFO day. Considering the possible growing trend towards remote work it is important to evaluate these "new domestic offices" comprehensively.

Knowledge of Undergraduate Students About Chronic Obstructive Pulmonary Disease in King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia

Aims Chronic obstructive pulmonary disease (COPD) is one of the most common causes of death worldwide. This study assesses the level of knowledge about COPD among undergraduate students that makes it different from other respiratory illnesses. Methods A cross-sectional study was conducted among undergraduate students at King Saud bin Abdulaziz University for Health Sciences (KSAU-HS). The Bristol Chronic obstructive pulmonary disease Knowledge Questionnaire (BCKQ) was used to evaluate the knowledge about COPD, epidemiology, symptoms, exercise, smoking, and breathlessness domains. The questionnaire was distributed among the different male colleges. Results There were 304 respondents from five colleges. The overall BCKQ mean score was 15.16±4.52 (maximum 30). The mean score was highest for the Colleges of Pharmacy (18.89±2.17) and Medicine (18.00±3.84), and the College of Science and Health Professions had the lowest score (11.56±5.58). The highest overall means for the different domains (max=5) were for smoking (2.19±1.2), and epidemiology (2.83±1.27), while symptoms of COPD (2.23±1.06) and breathlessness (1.96±1.13) were the lowest among the domains. Conclusions There was a low level of understanding among undergraduate students in general, but the Colleges of Medicine and Pharmacy had better knowledge. On the other hand, the College of Science and Health Professions had a lower score. This indicates some areas for improvement in the education program. Appropriate development in the education program is recommended, such as increasing the awareness of symptoms of COPD and other aspects of the disease.

Long-term exposure to ambient fine particulate matter and periodontitis: An observational study using nationally representative survey data

AIM

The rising prevalence of periodontitis imposes substantial burdens on individuals and society. Identifying environmental risk factors for periodontitis may contribute to tackling the global public health burden of it. This study aimed to assess the association between long-term exposure to PM2.5 and periodontitis in a nationally representative population from China.

MATERIALS AND METHODS

In this multi-centre cross-sectional study of 372 communities in 31 provinces of Mainland China, we used data from the Fourth National Oral Health Survey of China in 2015-2016, in combination with high-resolution gridded concentrations of fine particulate matter (PM2.5). Logistic regression was applied to assess the relationship between long-term PM2.5 exposure and the risk of periodontitis. In addition, we examined whether the association varied by individual characteristics, and estimated the exposure-response relationship and the risk of damaged tooth in each tooth quadrant.

RESULTS

A total of 8391 participants from 96 cities were diagnosed with periodontitis, accounting for 60.04% (8391/13,459) of the participants. For each 10 μg/m3 increment in 1-, 3- and 5-year average concentrations of PM2.5, the risk of total periodontitis increased by 9.0% (95% confidence interval: 6.0%, 12.0%), 8.0% (6.0, 11·0) and 7.0% (5.0, 10.0), respectively. Mild periodontitis was more strongly associated with PM2.5 exposure than moderate and severe periodontitis. The teeth in the lower anterior, lower posterior or upper anterior are more susceptible to the effect of PM2.5 on the periodontal pocket, calculus and bleeding gums.

CONCLUSIONS

Long-term exposure to PM2.5 is significantly associated with an increased risk of periodontitis in the nationally representative Chinese population. Considering the rising prevalence of periodontitis, considerable costs of treatment, and substantially adverse effects on individuals and society, these findings suggest that stricter air quality regulations may help ease the burden of periodontal disease.

Assessment of cellular senescence potential of PM2.5 using 3D human lung fibroblast spheroids in vitro model

Background

Epidemiological studies demonstrate that particulate matter 2.5 (PM2.5) exposure closely related to chronic respiratory diseases. Cellular senescence plays an important role in many diseases. However, it is not fully clear whether PM2.5 exposure could induce cellular senescence in the human lung. In this study, we generated a three-dimensional (3D) spheroid model using isolated primary human lung fibroblasts (HLFs) to investigate the effects of PM2.5 on cellular senescence at the 3D level.

Methods

3D spheroids were exposed to 25-100 μg/ml of PM2.5 in order to evaluate the impact on cellular senescence. SA-β-galactosidase activity, cell proliferation, and the expression of key genes and proteins were detected.

Results

Exposure of the HLF spheroids to PM2.5 yielded a more sensitive cytotoxicity than 2D HLF cell culture. Importantly, PM2.5 exposure induced the rapid progression of cellular senescence in 3D HLF spheroids, with a dramatically increased SA-β-Gal activity. In exploiting the mechanism underlying the effect of PM2.5 on senescence, we found a significant increase of DNA damage, upregulation of p21 protein levels, and suppression of cell proliferation in PM2.5-treated HLF spheroids. Moreover, PM2.5 exposure created a significant inflammatory response, which may be at least partially associated with the activation of TGF-β1/Smad3 axis and HMGB1 pathway.

Conclusions

Our results indicate that PM2.5 could induce DNA damage, inflammation, and cellular senescence in 3D HLF spheroids, which may provide a new evidence for PM2.5 toxicity based on a 3D model which has been shown to be more in vivo-like in their phenotype and physiology than 2D cultures.

Biomass-related PM2.5 induced inflammatory microenvironment via IL-17F/IL-17RC axis

Biomass exposure is a significant environmental risk factor for COPD, but the underlying mechanisms have not yet been fully elucidated. Inflammatory microenvironment has been shown to drive the development of many chronic diseases. Pollution exposure can cause increased levels of inflammatory factors in the lungs, leading to an inflammatory microenvironment which is prevalent in COPD. Our findings revealed that IL-17F was elevated in COPD, while exposure to biomass led to increased expression of IL-17F in both alveolar epithelial and macrophage cells in mice. Blocking IL-17F could alleviate the lung inflammation induced by seven days of biomass exposure in mice. We employed a transwell co-culture system to simulate the microenvironment and investigate the interactions between MLE-12 and MH-S cells. We demonstrated that anti-IL-17F antibody attenuated the inflammatory responses induced by BRPM2.5 in MLE-12 and MH-S co-cultured with BRPM2.5-MLE-12, which reduced inflammatory changes in microenvironment. We found that IL-17RC, an important receptor for IL-17F, played a key role in the interactions. Knockout of IL-17RC in MH-S resulted in inhibited IL-17F signaling and attenuated inflammatory response after MH-S co-culture with BRPM2.5-MLE-12. Our investigation suggests that BRPM2.5 induces lung epithelial-macrophage interactions via IL-17F/IL-17RC axis regulating the inflammatory response. These results may provide a novel strategy for effective prevention and treatment of biomass-related COPD.

Exploring the association of PM2.5 with lung cancer incidence under different climate zones and socioeconomic conditions from 2006 to 2016 in China

Air pollution generated by urbanization and industrialization poses a significant negative impact on public health. Particularly, fine particulate matter (PM2.5) has become one of the leading causes of lung cancer mortality worldwide. The relationship between air pollutants and lung cancer has aroused global widespread concerns. Currently, the spatial agglomeration dynamic of lung cancer incidence (LCI) has been seldom discussed, and the spatial heterogeneity of lung cancer's influential factors has been ignored. Moreover, it is still unclear whether different socioeconomic levels and climate zones exhibit modification effects on the relationship between PM2.5 and LCI. In the present work, spatial autocorrelation was adopted to reveal the spatial aggregation dynamic of LCI, the emerging hot spot analysis was introduced to indicate the hot spot changes of LCI, and the geographically and temporally weighted regression (GTWR) model was used to determine the affecting factors of LCI and their spatial heterogeneity. Then, the modification effects of PM2.5 on the LCI under different socioeconomic levels and climatic zones were explored. Some findings were obtained. The LCI demonstrated a significant spatial autocorrelation, and the hot spots of LCI were mainly concentrated in eastern China. The affecting factors of LCI revealed an obvious spatial heterogeneity. PM2.5 concentration, nighttime light data, 2 m temperature, and 10 m u-component of wind represented significant positive effects on LCI, while education-related POI exhibited significant negative effects on LCI. The LCI in areas with low urbanization rates, low education levels, and extreme climate conditions was more easily affected by PM2.5 than in other areas. The results can provide a scientific basis for the prevention and control of lung cancer and related epidemics.

Impact of air pollution on healthcare utilization in patients with bronchiectasis

Introduction

Air pollutants are increasingly recognized to affect long-term outcomes in patients with bronchiectasis. We aimed to figure out the association between air pollutants and the risk of healthcare utilization in patients with bronchiectasis.

Methods

Data for 1,029 subjects with bronchiectasis in Seoul were extracted. The air pollutants included particulate matter of 10 μm or less in diameter (PM10), particulate matter of 2.5 μm or less in diameter (PM2.5), sulfur dioxide (SO2), carbon monoxide (CO), ozone (O3), and nitrogen dioxide (NO2). The outcome was all-cause healthcare uses, defined as outpatient visit, emergency department visit, or hospitalization. The concentration-response curves between each air pollutant and relative risks for healthcare utilization were obtained.

Results

There were significant correlations between air pollutant concentrations and the risk of healthcare utilization, particularly for PM10, NO2, SO2, and CO. This risk was observed even at concentrations below the recommended safe thresholds for the general population. The slopes for the association between PM10 and NO2 and the risk of healthcare use showed a logarithmic growth pattern, with the steepest increase up to 30 μg/m3 and 0.030 parts per million (ppm), respectively. The curves for SO2 and CO showed an inverted U-shaped pattern, with a peak at 0.0045 ppm and a slow upward curve, respectively. No specific trends were observed for PM2.5 and O3 and the risk of healthcare use.

Discussion

Increased concentrations of PM10, NO2, SO2, and CO were associated with increased healthcare utilization in patients with bronchiectasis. For patients with bronchiectasis, there were no safety thresholds for those air pollutants, and even low levels of air pollutant exposure can negatively impact bronchiectasis outcomes.

Vardenafil alleviates cigarette smoke-induced chronic obstructive pulmonary disease by activating autophagy via the AMPK/mTOR signalling pathway: an in vitro and in vivo study

Chronic obstructive pulmonary disease (COPD) has always attracted global attention with its high prevalence, incidence rate, and mortality. Exposure to cigarette smoke is one of main causes of COPD. Therefore, it is still necessary to study its pathogenesis and find new therapeutic strategies for early COPD prevention and treatment. Vardenafil, a type 5 phosphodiesterase (PDE5) inhibitor, is known to have an efficient therapy in some cardiovascular, pulmonary, and vascular diseases, which is an important mechanism for COPD. However, it still loss relevant research on whether vardenafil is effective in COPD and its mechanism. In this study, the cigarette smoke inhalation was performed to establish cigarette smoke-induced COPD model using C57BL/6 mice and 16HBE cells were treated with cigarette smoke extract (CSE). Mice were treated with vardenafil for 30 d. Then condition of lung injury was evaluated using histological analysis. The content of cytokines and the number of inflammatory cells in lung tissues or bronchoalveolar lavage fluid were measured. Additionally, western blot analysis was employed to evaluate the activation of adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK)/mechanistic target of rapamycin (mTOR)-mediated autophagy in vitro. The results showed that vardenafil abolished CSE's effect by activating autophagy via the AMPK/mTOR signalling pathway in vitro. Vardenafil attenuated cigarette smoke-induced lung injury and inflammation response by activating autophagy via the AMPK/mTOR signalling pathway in vivo. These results provide valuable insights into the molecular mechanisms underlying vardenafil's beneficial effects in cigarette smoke-induced COPD treatment. In conclusion, vardenafil alleviates cigarette smoke-induced experimental COPD by activating autophagy via the AMPK/mTOR signalling pathway.

Health benefits of reducing ambient levels of fine particulate matter: a mortality impact assessment in Taiwan

While numerous studies have found a relationship between long-term exposure to airborne fine particulate matter (PM2.5) and higher risk of death, few investigations examined the contribution that a reduction of exposure to ambient PM2.5 levels might exert on mortality rates. This study aimed to collect data on changes in annual average ambient levels of PM2.5 from 2006 to 2020 and consequent health impact in public health in 65 municipalities in Taiwan. Avoidable premature mortality was used here as an indicator of adverse health impact or health benefits. Annual PM2.5 levels were averaged for the years 2006, 2010, and 2020. In accordance with World Health Organization (WHO) methodology, differences were estimated in the number of deaths attributed to ambient PM2.5 exposure which were derived from concentration-response data from prior epidemiological studies. PM2.5 concentrations were found to have been decreased markedly throughout Taiwan over the two-decade study. As the PM2.5 concentrations fell, so was the health burden as evidenced by number of deaths concomitantly reduced from 22.4% in 2006 to 8.47% in 2020. Data demonstrated that reducing annual mean levels of PM2.5 to PM10 ug/m3 was associated with decrease in the total burden of mortality, with a 2.22-13.18% fall in estimated number of PM2.5-related deaths between 2006 and 2020. Based upon these results, these declines in ambient PM2.5 levels were correlated with significant improvement in public health (health benefits) and diminished number of deaths in Taiwan.

Prediction of atmospheric pollutants in urban environment based on coupled deep learning model and sensitivity analysis

Accurate and efficient predictions of pollutants in the atmosphere provide a reliable basis for the scientific management of atmospheric pollution. This study develops a model that combines an attention mechanism, convolutional neural network (CNN), and long short-term memory (LSTM) unit to predict the O₃ and PM_2.5 levels in the atmosphere, as well as an air quality index (AQI). The prediction results given by the proposed model are compared with those from CNN-LSTM and LSTM models as well as random forest and support vector regression models. The proposed model achieves a correlation coefficient between the predicted and observed values of more than 0.90, outperforming the other four models. The model errors are also consistently lower when using the proposed approach. Sobol-based sensitivity analysis is applied to identify the variables that make the greatest contribution to the model prediction results. Taking the COVID-19 outbreak as the time boundary, we find some homology in the interactions among the pollutants and meteorological factors in the atmosphere during different periods. Solar irradiance is the most important factor for O₃, CO is the most important factor for PM_2.5, and particulate matter has the most significant effect on AQI. The key influencing factors are the same over the whole phase and before the COVID-19 outbreak, indicating that the impact of COVID-19 restrictions on AQI gradually stabilized. Removing variables that contribute the least to the prediction results without affecting the model prediction performance improves the modeling efficiency and reduces the computational costs.

A nationwide survey of polycyclic aromatic hydrocarbons (PAHs) in household dust in China: spatial distribution, sources, and health risk assessment

As a carrier of toxic substances, household dust has a great impact on human health. Here we collected 73 household dust samples from 27 provinces and 1 municipality in China to investigate the levels, spatial distribution, sources, and carcinogenic risk of 16 polycyclic aromatic hydrocarbons (PAHs). The total concentrations of 14 detected PAHs (∑₁₄ PAHs) ranged from 3.72 to 60,885 ng g^-1. High ∑₁₄ PAHs were found in Northeast and Southwest China. High molecular weights (HMW) PAHs (4-6 rings) were predominant PAHs in most dust samples, accounting for 93.6% of ∑₁₄ PAHs. Household fuel, cooking frequency, air conditioning, and smoking were the main factors influencing PAH concentrations in household dust. Principal component analysis model indicated that fossil combustion (81.5%) and biomass combustion and vehicle exhaust (8.1%) are the primary sources of PAHs. Positive matrix factorization model suggested that household cooking and heating contributed about 70% of ∑₁₄ PAHs, and smoking contributed another 30%. The values of benzo[a]pyrene equivalent in rural dust were found to be higher than those in urban dust. The sum of toxic equivalents (TEQs) of 14 PAHs were in range of 0.372-7241 ng g^-1, in which 7 HMW PAHs accounted for 98.0 ± 1.98% of the total TEQs. Monte Carlo Simulation showed a low to moderate potential carcinogenic risk of PAHs in household dusts. This study documents comprehensive information on human exposure to PAHs in household dust at a national-scale.

Targeting Lung-Gut Axis for Regulating Pollution Particle-Mediated Inflammation and Metabolic Disorders

Cigarette smoking (CS) or ambient particulate matter (PM) exposure is a risk factor for metabolic disorders, such as insulin resistance (IR), increased plasma triglycerides, hyperglycemia, and diabetes mellitus (DM); it can also cause gut microbiota dysbiosis. In smokers with metabolic disorders, CS cessation decreases the risks of serious pulmonary events, inflammation, and metabolic disorder. This review included recent studies examining the mechanisms underlying the effects of CS and PM on gut microbiota dysbiosis and metabolic disorder development; one of the potential mechanisms is the disruption of the lung-gut axis, leading to gut microbiota dysbiosis, intestinal dysfunction, systemic inflammation, and metabolic disease. Short-chain fatty acids (SCFAs) are the primary metabolites of gut bacteria, which are derived from the fermentation of dietary fibers. They activate G-protein-coupled receptor (GPCR) signaling, suppress histone deacetylase (HDAC) activity, and inhibit inflammation, facilitating the maintenance of gut health and biofunction. The aforementioned gut microbiota dysbiosis reduces SCFA levels. Treatment targeting SCFA/GPCR signaling may alleviate air pollution-associated inflammation and metabolic disorders, which involve lung-gut axis disruption.

Determinants Analysis Regarding Household Chemical Indoor Pollution

Indoor household pollution is not yet sufficiently studied in the general population. Over 4 million people die prematurely every year due to air pollution in households. This study aimed to propose quantitative data research through the administration of a KAP (Knowledge, Attitudes, and Practices) Survey Questionnaire. This cross-sectional study administered questionnaires to adults from the metropolitan city of Naples (Italy). Three Multiple Linear Regression Analyses (MLRA) were developed, including Knowledge, Attitudes, and Behavior regarding household chemical air pollution and the related risks. One thousand six hundred seventy subjects received a questionnaire to be filled out and collected anonymously. The mean age of the sample was 44.68 years, ranging from 21-78 years. Most of the people interviewed (76.13%) had good attitudes toward house cleaning, and 56.69% stated paying attention to cleaning products. Results of the regression analysis indicated that positive attitudes were significantly higher among subjects who graduated, with older age, male and non-smokers, but they were correlated with lower knowledge. In conclusion, a behavioral and attitudinal program targeted those with knowledge, such as younger subjects with high educational levels, but do not engage in correct practices towards household indoor chemical pollution.

Association of outdoor air pollution, lifestyle, genetic factors with the risk of lung cancer: A prospective cohort study

OBJECTIVES

The effect of air pollution exposure on incident lung cancer remains uncertain, and the modifying role of lifestyle and genetic susceptibility in association between air pollution and lung cancer is ambiguous.

METHODS

A total of 367,623 participants from UK biobank cohort were enrolled in the analysis. The concentrations of particle matter (PM_2.5, PM₁₀), nitrogen dioxide (NO₂), and nitrogen oxides (NO_x), were evaluated by land-use regression model. Cox proportional hazard model was applied to assess the associations between air pollution and incident lung cancer. A lifestyle risk score and a polygenic risk score were established to investigate whether lifestyle and heritable risk could modify the effect of air pollution on lung cancer risk.

RESULTS

Per interquartile range (IQR) increment in annual concentrations of PM_2.5 (HR = 1.22, 95% CI, 1.15∼1.30), NO₂ (HR = 1.19, 95% CI, 1.10∼1.27), and NO_x (HR = 1.14, 95% CI, 1.09∼1.20) were associated with increased risk of lung cancer. We observed an additive interaction between air pollution including PM_2.5 and NO_x and lifestyle or genetic risk. Individuals with high air pollution exposure, poor lifestyle and high genetic risk had the highest risk of incident lung cancer.

CONCLUSION

Long-term exposures to air pollution is associated with increased risk of lung cancer, and this effect was modified by lifestyle or genetic risk. Integrated interventions for environmental pollution by government and adherence to healthy lifestyle by individuals are advocated for lung cancer prevention.

Short-term associations of PM2.5 and PM2.5 constituents with immune biomarkers: A panel study in people living with HIV/AIDS

Studies on associations of fine particulate matter (PM_2.5) with immunity in people living with HIV/AIDS (PLWHA) were absent. We aimed to explore whether changes of immune biomarkers were associated with short-term exposure to PM_2.5 in PLWHA. Based on a panel study in Wuhan, we selected 163 PLWHA as participants with up to 4 repeated visits from March 2020 to January 2021. Immune biomarkers, including CD4⁺T cell count, CD8⁺T cell count, HIV viral load (VL) and CD4⁺T/CD8⁺T ratio were tested for all participants at each visit. Residential exposures of PM_2.5 and PM_2.5 constituents for each participant were assessed using spatial-temporal models. Linear mixed-effect models and general linear mixed models were applied to evaluate the associations between PM_2.5 and immune biomarkers. To estimate the combined effect of PM_2.5 constituents, weighted quantile sum regression and Bayesian kernel machine regression were employed. Each 10 μg/m³ increase of 7-day average PM_2.5 concentrations was associated with an 8.75 cells/mm³ (95%CI: -15.55, -1.98) decrease in CD4⁺T cell count and a 92% (OR: 1.92, 95%CI: 1.43, 2.58) increased odds ratio of detectable HIV VL. However, the odds ratio of inverted CD4⁺T/CD8⁺T was only positively associated with PM_2.5 concentrations at lag2 day (OR:1.27, 95%CI:1.02, 1.57). CD4⁺T may be a potential mediator between PM_2.5 and detectable HIV VL with 3.83% mediated proportion. Besides, the combined effect of PM_2.5 chemical constituents indicated that NO₃^- and SO₄^2- were the main constituents in reducing CD4⁺T cell count and increasing odds ratio of detectable HIV VL. Our finding revealed that short-term exposure to PM_2.5 was negatively associated with CD4⁺T cell count but positively related to the odds ratio of detectable HIV VL in PLWHA. This research may provide new evidence in associations between PM_2.5 and immune biomarkers as well as improving prognosis of PLWHA.

Particulate Matter and Its Components Induce Alteration on the T-Cell Response: A Population Biomarker Study

Compared with the T-cell potential of particulate matter (PM) in animal studies, comprehensive evaluation on the impairments of T-cell response and exposure-response from PM and its components in human population is limited. There were 768 participants in this study. We measured environmental PM and its polycyclic aromatic hydrocarbons (PAHs) and metals and urinary metabolite levels of PAHs and metals among population. T lymphocyte and its subpopulation (CD4⁺ T cells and CD8⁺ T cells) and the expressions of T-bet, GATA3, RORγt, and FoxP3 were measured. We explored the exposure-response of PM compositions by principal component analysis and mode of action by mediation analysis. There was a significant decreasing trend for T lymphocytes and the levels of T-bet and GATA3 with increased PM levels. Generally, there was a negative correlation between PM, urinary 1-hydroxypyrene, urinary metals, and the levels of T-bet and GATA3 expression. Additionally, CD4⁺ T lymphocytes were found to mediate the associations of PM_2.5 with T-bet expression. PM and its bound PAHs and metals could induce immune impairments by altering the T lymphocytes and genes of T-bet and GATA3.

Long-term exposure to ambient air pollution and asthma symptom score in the CONSTANCES cohort

BACKGROUND

The asthma symptom score allows to consider asthma as a continuum and to investigate its risk factors. One previous study has investigated the association between asthma score and air pollution and only for nitrogen dioxide (NO₂). We aimed to study the associations between particulate matter with an aerodynamic diameter lower than 2.5 µm (PM_2.5), black carbon (BC) and NO₂ and the asthma symptom score in adults from CONSTANCES, a French population-based cohort.

METHODS

Asthma symptom score (range: 0-5) was based on the number of five self-reported symptoms of asthma in the last 12 months. Annual individual exposure to PM_2.5, BC and NO₂ was estimated at participants' residential address using hybrid land-use regression models. Cross-sectional associations of each pollutant with asthma symptom score were estimated using negative binomial regressions adjusted for age, sex, smoking status and socioeconomic position. Associations with each symptom were estimated using logistic regression. The effect of BC independent of total PM_2.5 was investigated with a residual model.

RESULTS

Analyses were conducted on 135 165 participants (mean age: 47.2 years, 53.3% women, 19.0% smokers, 13.5% ever asthma). The ratio of mean score was 1.12 (95% CI 1.10 to 1.14), 1.14 (95% CI 1.12 to 1.16) and 1.12 (95% CI 1.10 to 1.14) per one IQR increase of PM_2.5 (4.86 µg/m³), BC (0.88 10^-5 m^-1) and NO₂ (17.3 µg/m³). Positive and significant associations were also found for each asthma symptom separately. BC effect persisted independently of total PM_2.5.

CONCLUSION

Exposure to each pollutant was associated with increased asthma symptom score in adults. This study highlights that BC could be one of the most harmful particulate matter components.

Ambient particulate matter exposure causes visual dysfunction and retinal neuronal degeneration

PM_2.5 pollution is related to neurotoxic and vascular effects in eye diseases such as glaucoma. This study investigates the adverse effects of PM_2.5 exposure on visual function and retinal neurons. A versatile aerosol concentration enrichment system was used to expose mice to either control air or PM_2.5 polluted air. Six months after PM_2.5 exposure, visual function was measured by electroretinography (ERG). Hematoxylin and eosin staining and immunofluorescence staining were used for histopathological analysis. Protein markers of apoptosis, astrocytic reactivity, inflammatory cytokines, lipid peroxidation, protein nitration and DNA damage response were quantified with ELISA, western blot or detected using immunofluorescence and immunohistochemistry. After six months of exposure, PM_2.5-exposed mice responded poorly to light stimuli compared with those exposed to the control air. PM_2.5 exposure caused retinal thinning and reduction in the expression of retinal ganglion cell-selective marker RNA-binding protein with multiple splicing (RBPMS). Further, positive TUNEL staining was observed in the inner nucleus and outer nuclear layers of the retinae after exposure to PM_2.5, which was accompanied by the activation of apoptosis signaling molecules p53, caspase-3 and Bax. PM_2.5 induced the release of inflammatory cytokines including tumor necrosis factor-α and cleaved interleukin-1β. Furthermore, increased levels of 8-OHdG and γ-H2AX in the mouse retinea were indicative of DNA single and double strand breaks by PM_2.5 exposure, which activated PARP-1 mediated DNA damage and repair. In conclusion, this study demonstrates sub-chronic systemic exposure to concentrated PM_2.5 causes visual dysfunction and retinal neuronal degeneration. DATA AVAILABILITY: The datasets during and/or analyzed during the current study available from the corresponding author on reasonable request.

Airborne transmission of biological agents within the indoor built environment: a multidisciplinary review

The nature and airborne dispersion of the underestimated biological agents, monitoring, analysis and transmission among the human occupants into building environment is a major challenge of today. Those agents play a crucial role in ensuring comfortable, healthy and risk-free conditions into indoor working and leaving spaces. It is known that ventilation systems influence strongly the transmission of indoor air pollutants, with scarce information although to have been reported for biological agents until 2019. The biological agents' source release and the trajectory of airborne transmission are both important in terms of optimising the design of the heating, ventilation and air conditioning systems of the future. In addition, modelling via computational fluid dynamics (CFD) will become a more valuable tool in foreseeing risks and tackle hazards when pollutants and biological agents released into closed spaces. Promising results on the prediction of their dispersion routes and concentration levels, as well as the selection of the appropriate ventilation strategy, provide crucial information on risk minimisation of the airborne transmission among humans. Under this context, the present multidisciplinary review considers four interrelated aspects of the dispersion of biological agents in closed spaces, (a) the nature and airborne transmission route of the examined agents, (b) the biological origin and health effects of the major microbial pathogens on the human respiratory system, (c) the role of heating, ventilation and air-conditioning systems in the airborne transmission and (d) the associated computer modelling approaches. This adopted methodology allows the discussion of the existing findings, on-going research, identification of the main research gaps and future directions from a multidisciplinary point of view which will be helpful for substantial innovations in the field.

Mathematical modeling in the health risk assessment of air pollution-related disease burden in China: A review

This review paper covers an overview of air pollution-related disease burden in China and a literature review on the previous studies which have recently adopted a mathematical modeling approach to demonstrate the relative risk (RR) of air pollution-related disease burden. The associations between air pollution and disease burden have been explored in the previous studies. Therefore, it is necessary to quantify the impact of long-term exposure to ambient air pollution by using a suitable mathematical model. The most common way of estimating the health risk attributable to air pollution exposure in a population is by employing a concentration-response function, which is often based on the estimation of a RR model. As most of the regions in China are experiencing rapid urbanization and industrialization, the resulting high ambient air pollution is influencing more residents, which also increases the disease burden in the population. The existing RR models, including the integrated exposure-response (IER) model and the global exposure mortality model (GEMM), are critically reviewed to provide an understanding of the current status of mathematical modeling in the air pollution-related health risk assessment. The performances of different RR models in the mortality estimation of disease are also studied and compared in this paper. Furthermore, the limitations of the existing RR models are pointed out and discussed. Consequently, there is a need to develop a more suitable RR model to accurately estimate the disease burden attributable to air pollution in China, which contributes to one of the key steps in the health risk assessment. By using an updated RR model in the health risk assessment, the estimated mortality risk due to the impacts of environment such as air pollution and seasonal temperature variation could provide a more realistic and reliable information regarding the mortality data of the region, which would help the regional and national policymakers for intensifying their efforts on the improvement of air quality and the management of air pollution-related disease burden.

Polycyclic Aromatic Hydrocarbons Induced by Smoking and Air Pollution: Correlation with Oxidative Stress in Chronic Obstructive Pulmonary Disease Patients

Oxidative stress is induced by tobacco smoking and is also associated with exposure to air pollution, which are two of the most important risk factors for chronic obstructive pulmonary disease (COPD). The aim of this study was to correlate tobacco use and exposure to air pollution with oxidative stress markers useful in clinical practice in patients with COPD. A total of 102 patients were included and the levels of polycyclic aromatic hydrocarbons (PAHs), malondialdehyde, uric acid and number of packs-years (PY) were determined. Also, six different ratios were used to assess the source of exposure. The results obtained in this study show an admission of pollutants according to smoking status (former smokers/smoker/non-smokers) quantified in average total concentrations for the group of patients with COPD of 4.12 ng/mL, 6.76 ng/mL, 6.04 ng/mL. The six ratios used show that in COPD, the content of PAHs in the blood could be a result of diesel emissions and fuel combustion. Uric acid levels were lower in the smoker group of COPD patients (mean = 5.21 mg/dL), which indicates that oxidative stress is intensified with each cigarette smoked. Additionally, high concentrations of malondialdehyde were quantified for smoking patients diagnosed with COPD (mean = 2.72 µmol/L) compared to former smokers (mean = 2.43 µmol/L) and non-smoking (mean = 2.32 µmol/L) patients, which is another indicator of the implication of smoking in oxidative stress in COPD patients.

Field measurements of indoor and community air quality in rural Beijing before, during, and after the COVID-19 lockdown

The coronavirus (COVID-19) lockdown in China is thought to have reduced air pollution emissions due to reduced human mobility and economic activities. Few studies have assessed the impacts of COVID-19 on community and indoor air quality in environments with diverse socioeconomic and household energy use patterns. The main goal of this study was to evaluate whether indoor and community air pollution differed before, during, and after the COVID-19 lockdown in homes with different energy use patterns. Using calibrated real-time PM_2.5 sensors, we measured indoor and community air quality in 147 homes from 30 villages in Beijing over 4 months including periods before, during, and after the COVID-19 lockdown. Community pollution was higher during the lockdown (61 ± 47 μg/m³ ) compared with before (45 ± 35 μg/m³ , p < 0.001) and after (47 ± 37 μg/m³ , p < 0.001) the lockdown. However, we did not observe significantly increased indoor PM_2.5 during the COVID-19 lockdown. Indoor-generated PM_2.5 in homes using clean energy for heating without smokers was the lowest compared with those using solid fuel with/without smokers, implying air pollutant emissions are reduced in homes using clean energy. Indoor air quality may not have been impacted by the COVID-19 lockdown in rural settings in China and appeared to be more impacted by the household energy choice and indoor smoking than the COVID-19 lockdown. As clean energy transitions occurred in rural households in northern China, our work highlights the importance of understanding multiple possible indoor sources to interpret the impacts of interventions, intended or otherwise.

Health benefit/burden, PM2 .5 removal effectiveness, and power consumption based comparison of common residential air-cleaning technologies in the United States

This modeling study compared the common air cleaners in U.S. residences based on averted disability-adjusted life years (DALYs) related to indoor PM_2.5 concentration reduction and the DALYs resulted from carbon-di-oxide (CO₂ ) emissions from power consumption. The technologies compared include mechanical fibrous filters, electret fibrous filters, and electronic air cleaners. For DALYs estimation, the indoor PM_2.5 concentration and power consumption were first calculated and compared. These were then multiplied by the respective health damage factors. Air cleaners were compared under several indoor particle size distributions scenarios. A methodology was developed to evaluate the influence of the aging of air cleaners on the selected comparison criteria. The results suggest that the averted DALYs from indoor PM_2.5 concentration reduction far supersedes the indirect DALYs associated with the operational power consumption of the air cleaners. Hence, the DALY-based ranking of the air cleaners considered was the same as that of their effectiveness to reduce indoor PM_2.5 concentrations. However, the result should be taken with care as only the use-phase of air cleaners was considered. For future study, a complete life-cycle assessment is recommended. Considering aging can change the ranking of the air cleaners and is thus advised to be incorporated in further studies.

Indoor Air Pollution and Decision-Making Behavior: An Interdisciplinary Review

The human brain is constantly exposed to air pollutants, some of which might be disruptive or even lethal to certain neurons implicated in abstract features of cognitive function. In this review, we present new evidence from behavioral and neural studies in humans, suggesting a link between indoor fine particulate matter and decision-making behavior. To illustrate this relationship, we use qualitative sources, such as historical documents of the Vietnam War to develop hypotheses of how aerial transmission of pollutants might obstruct alternative choices during the evaluation of policy decisions. We first describe the neural circuits driving decision-making processes by addressing how neurons and their cognate receptors directly evaluate and transduce physical phenomena into sensory perceptions that allow us to decide the best course of action among competing alternatives. We then raise the possibility that indoor air pollutants might also impact cell-signaling systems outside the brain parenchyma to further obstruct the computational analysis of the social environment. We also highlight how particulate matter might be pathologically integrated into the brain to override control of sensory decisions, and thereby perturb selection of choice. These lines of research aim to extend our understanding of how inhalation of airborne particulates and toxicants in smoke, for example, might contribute to cognitive impairment and negative health outcomes.

Systematic review of changed smoking behaviour, smoking cessation and psychological states of smokers according to cigarette type during the COVID-19 pandemic

OBJECTIVES

Although the global COVID-19 pandemic has increased interest in research involving high-risk smokers, studies examining changed smoking behaviours, cessation intentions and associated psychological states among smokers are still scarce. This study aimed to systematically review the literature related to this subject.

DESIGN

A systematic review of published articles on cigarettes and COVID-19-related topics DATA SOURCES: Our search was conducted in January 2021. We used the keywords COVID-19, cigarettes, electronic cigarettes (e-cigarettes) and psychological factors in PubMed and ScienceDirect and found papers published between January and December 2020.

DATA SELECTION

We included articles in full text, written in English, and that surveyed adults. The topics included smoking behaviour, smoking cessation, psychological state of smokers and COVID-19-related topics.

DATA EXTRACTION AND SYNTHESIS

Papers of low quality, based on quality assessment, were excluded. Thirteen papers were related to smoking behaviour, nine papers were related to smoking cessation and four papers were related to psychological states of smokers.

RESULTS

Owing to the COVID-19 lockdown, cigarette users were habituated to purchasing large quantities of cigarettes in advance. Additionally, cigarette-only users increased their attempts and willingness to quit smoking, compared with e-cigarette-only users.

CONCLUSIONS

Owing to the COVID-19 outbreak, the intention to quit smoking was different among smokers, according to cigarette type (cigarette-only users, e-cigarette-only users and dual users). With the ongoing COVID-19 pandemic, policies and campaigns to increase smoking cessation intentions and attempts to quit smoking among smokers at high risk of COVID-19 should be implemented. Additionally, e-cigarette-only users with poor health-seeking behaviour require interventions to increase the intention to quit smoking.

Exposure of Individuals in Europe to Air Pollution and Related Health Effects

Air pollutants, especially PM2.5 and NO₂, are associated with adverse health impacts, as shown by numerous epidemiological studies. In these studies, the observed health impacts have been correlated with ambient concentrations, mainly taken from air pollution monitoring stations. However, individuals are harmed by the pollutants in the inhaled air at the places where they stay, and thus, the concentration of pollutants in the inhaled air is obviously a better indicator for health impacts than the ambient concentration at a monitoring station. Furthermore, the current method for estimating the occurrence of chronic diseases uses annual average concentrations as indicator. However, according to current hypotheses, chronic diseases, especially chronic mortality, develop through the exposure to pollutants over many years, maybe up to a full lifetime. Thus in this study, a methodology and a computer-aided probabilistic model system are described for calculating the exposure of a person to PM2.5 and NO₂ over the whole lifetime where the person is characterized by attributes such as age, gender, place of residence and work as well as socioeconomic status. The model system contains a “life course trajectory model”, which estimates the course of the education and professional development for the past lifetime of a person, whose present socioeconomic status is known. Furthermore, a “time-activity model” estimates at which places (so-called micro-environments) a person with a certain socioeconomic status stayed and how long he stayed there within a certain year. The concentrations of air pollutants in indoor environments are calculated with a “mass-balance model”, the outdoor concentrations with “atmospheric models”. Finally, the results of these models are combined to estimate the annual average exposure for the life years of individuals and population subgroups. The exposure is then used to estimate and monetize health impacts. The exposures and health impacts for a number of population subgroups in Europe are presented. For instance, a European citizen, who was 70 years old in 2015, has been exposed to around 25 μg/m³ of PM2.5 during his lifetime above the age of 30, which is associated with a reduction of life expectancy of 13.4 days per year of exposure above 30.

Probabilistic health risk assessment and monetization based on benzene series exposure in newly renovated teaching buildings

To meet the needs of the rapid development of education, there have been growing investments in the issue of university infrastructures. However, few studies have paid attention to the assessment and monetization of health risks in newly renovated teaching buildings. In this study, concentrations of the benzene series (BTEX) group were measured in five areas of three newly renovated teaching buildings. A total of 135 BTEX samples were collected using passive diffusion monitors and analyzed by GC-FID. Human health risk assessments were conducted by using probabilistic methods for four types of population exposure to BTEX. The results showed that the cancer risk of benzene accounted for most of the total in each group. There was over 90% probability of excess cancer risks in the areas within the tested buildings; and the non-cancer risks were all within the acceptable level. The health risks of men were greater than those of women, and those of teachers were higher than those of students. The model calculation results of Disability-Adjusted Life Year (DALY) and Willingness to Pay (WTP) indicated that the average price that society was willing to pay to offset the health damage caused in these newly renovated teaching buildings was 381.35 yuan/year. For the first time, this study highlights the health risks of newly built teaching buildings in universities, points out the urgent need to improve the control of BTEX sources in this type of indoor environment; moreover, it provides theoretical support for the society and occupational protection departments to compensate for the health damage to professionals.

The botanical biofiltration of volatile organic compounds and particulate matter derived from cigarette smoke

Despite the growing use of control measures, environmental tobacco smoke (ETS) remains a significant pollutant source in indoor air in many areas of the world. Current control methods for reducing ETS exposure are inadequate to protect public health in environments where cigarettes are smoked. An alternative solution is botanical biofiltration which has previously been shown to lower concentrations of volatile organic compounds (VOCs) and particulate matter (PM) from a range of polluted air streams. This study is the first to assess the potential of a botanical biofilter with the species Spathiphyllum wallisii (Peace Lily) for the removal of cigarette-derived VOCs and all size fractions of PM. Single pass removal efficiencies of 43.26% for total VOCs and 34.37% for total suspended particles were achieved. The botanical biofilter reduced the concentrations of a range of harmful ETS chemicals including nicotine, limonene, and toluene. Evaluation of the re-emission of ETS constituents filtered by the botanical biofilter revealed no particle resuspension or off gassing. The results demonstrate the potential of botanical biofilters to reduce public ETS exposure, although further research is needed to improve upon and ensure the efficiency of these systems for practical applications.

Global burden of chronic obstructive pulmonary disease attributable to ambient particulate matter pollution and household air pollution from solid fuels from 1990 to 2019

We aimed to estimate the spatiotemporal trends in the global burden of chronic obstructive pulmonary disease (COPD) attributable to both household air pollution from solid fuels (HAP) and ambient particulate matter (APM) from 1990 to 2019 and compared the possible differences between the burdens attributable to APM and HAP. The number of deaths, disability-adjusted life-years (DALYs), and years of life lost (YLLs) of COPD attributable to HAP from solid fuels and APM during 1990-2019 were extracted from the Global Burden of Diseases Study 2019. The proportion of YLLs in DALYs and average YLLs per COPD death were also calculated. Subgroup analyses by sex, age, and socio-demographic index (SDI) were conducted. The estimated annual percentage change (EAPC) was used to assess the temporal trend of age-standardized rate of mortality (ASMR) and DALYs (ASDR). Over the past 30 years, we observed a clear downward trend in COPD deaths attributable to HAP and an upward trend by 97.61% in COPD deaths attributable to APM. The global COPD burden attributable to APM in 2019 was higher than those due to HAP, except in low-SDI regions. For both HAP and APM, YLLs continued to predominate in DALYs of COPD, with an average YLLs per death of more than 10 years in different regions. The ASMR was higher in males and lower in high-SDI regions. The ASMR and ASDR attributable to HAP decreased globally in all age groups during 1990-2019, while those attributable to APM increased among people older than 80 years and in regions with lower SDI. Our study reveals an increasing trend in APM-attributable COPD burden over the past three decades. Comparatively, the global burden due to HAP decreased markedly, but it was still pronounced in low-SDI regions. Continued efforts on PM mitigation are needed for COPD prevention.

Risk factors on healthcare-associated infections among tuberculosis hospitalized patients in China from 2001 to 2020: a systematic review and meta-analysis

Background

China has been still suffering from high burden attributable to tuberculosis (TB) and healthcare-associated infections (HAIs). TB patients are at high risk to get HAIs. Evidence-based guidelines or regulations to constrain the rising HAIs among TB hospitalized patients are needed in China. The aim of this systematic review and meta-analysis is to investigate the risk factors associated with HAIs among TB hospitalized patients in Chinese hospitals.

Methods

Medline, EMBASE and Chinese Journals Online databases were searched. The search was limited to studies published from January 1st 2001 to December 31st 2020. Meta-analyses of ORs of the risk factors between patients with HAIs and patients without HAIs among TB hospitalized patients were estimated. Heterogeneity among studies was assessed based on the \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\widehat{{\uptau }}$$\end{document}τ^² and I² statistics to select the meta-analysis model. Review Manager 5.3 was employed and P < 0.05 was considered as statistical significance.

Results

851 records were filtered from the databases, of which 11 studies were included in the quantitative meta-analysis. A total of 11,922 TB patients were included in the systematic review and meta-analysis, of which 1133 were diagnosed as having HAIs. Age older than 60 years (OR: 2.89 [2.01–4.15]), complications (OR: 3.28 [2.10–5.13]), diabetes mellitus (OR: 1.63 [1.22–2.19]), invasive procedure (OR: 3.80 [2.25–6.42]), longer than 15 hospitalization days (OR: 2.09 [1.64–2.64]), secondary tuberculosis (OR: 2.25 [1.48–3.42]), smoking (OR: 1.40[1.02–1.93]), underlying disease (OR: 2.66 [1.53–4.62]), and use of antibiotics (OR: 2.77 [2.35–3.27]) were the main risk factors associated with HAIs among TB hospitalized patients with a statistical significance (P < 0.05).

Conclusions

Age older than 60 years, presence of complications, presence of diabetes mellitus, invasive procedure, longer than 15 hospitalization days, secondary tuberculosis, smoking, presence of underlying disease, and use of antibiotics were the main risk factors which had a negative impact on HAIs among TB hospitalized patients in Chinese hospitals. These findings provided evidence for policy makers and hospital managers to make effective infection prevention and control measures to constrain the rising HAIs. It is also required that more cost-effective infection prevention and control measures should be widely applied in routinely medical treatment and clinical management to reduce the occurrence of HAIs among TB hospitalized patients.

Supplementary information

The online version contains supplementary material available at 10.1186/s12879-022-07364-9.

Changes in Personal Exposure to Fine Particulate Matter (PM2.5) during the Spring 2020 COVID-19 Lockdown in the UK: Results of a Simulation Model

Objectives: Policy responses to the COVID-19 pandemic in 2020 led to behaviour changes in the UK’s population, including a sudden shift towards working from home. These changes may have affected overall exposure to fine particulate matter (PM2.5), an air pollutant and source of health harm. We report the results of a simulation model of a representative sample of the UK’s population, including workers and non-workers, to estimate PM2.5 exposure before and during the pandemic. Methods: PM2.5 exposure was simulated in April and August 2017–2020 for 10,000 individuals across the UK drawn from the 2011 nationwide census. These data were combined with data from the UK’s ambient PM2.5 monitoring network, time use data and data on relevant personal behaviour before and during the first stage of the pandemic (such as changes in smoking and cooking). Results: The simulated exposures were significantly different between each year. Changes in ambient PM2.5 resulted in regional and temporal variation. People living in homes where someone smoked experienced higher exposure than those in smoke-free homes, with an increase of 4 µg/m3 in PM2.5 exposure in 2020. Conclusions: Changes in PM2.5 exposure were minimal for most individuals despite the simulated increases in cooking activity. Those living in smoking homes (estimated to be around 11% of the UK population) experienced increased exposure to PM2.5 during COVID lockdown measures and this is likely to have increased mortality and morbidity among this group. Government policy should address the risk of increased exposure to second-hand smoke in the event of future COVID-19-related restrictions.

lncRNA AABR07005593.1 potentiates PM2.5-induced interleukin-6 expression by targeting MCCC1

BACKGROUND

Fine particle pollution, specifically pollution by fine particulate matter (PM_2.5), remains a significant concern in developing countries and plays an important role in the development and progression of respiratory diseases. Increasing evidences have demonstrated that long non-coding RNAs (lncRNAs) may act as vital molecules by binding to specific RNA-binding protein (RBP); however, their relationship with PM_2.5 pollution is largely unexplored.

OBJECTIVE

We investigated the association between lncRNA and respiratory system inflammation caused by PM_2.5.

METHODS

PM_2.5 components were detected by gas chromatography-mass spectrometry (GC-MS), inductively coupled plasma-mass spectrometry (ICP-MS), and ionic chromatography. We established an inflammation model of PM_2.5-induced toxicity in vivo (male and female SD rats, 0, 25, 50 and 100 mg/k PM_2.5, 1, 7 and 14 days, single non-invasive tracheal instillation) and in vitro (rat alveolar macrophage cell line (NR8383), 0, 50, 100, 200, 400 μM PM_2.5 for 24, 48, and 72 h). lncRNA high-throughput sequencing (lncRNA-seq) was used to investigate lncRNA profiles in PM_2.5-treated NR8383 cells, and RNA interference (RNAi) was applied to explore the function of the target lncRNA. The mechanisms associated with specific lncRNAs were explored using comprehensive identification of RNA-binding proteins by mass spectrometry (ChIRP-MS) and western blot.

RESULTS

PM_2.5-treated NR8383 cells and SD rats exhibited respiratory inflammation. lncRNA AABR07005593.1 was a pro-inflammatory factor that regulated IL-6 levels. Mechanistically, ChIRP-MS and western blot analyses revealed that highly expressed lncRNA AABR07005593.1 interacted with MCCC1 to involve in the activation of NF-κB pathway, and ultimately promoted the expression of IL-6.

CONCLUSION

This study demonstrated that PM_2.5 induced inflammation in vivo and in vitro. Furthermore, lncRNA AABR07005593.1 bound to MCCC1 to potentiated IL-6 expression. Therefore, lncRNA AABR07005593.1 may act as a potential biomarker for PM_2.5 inflammation.

Long-term exposures to PM2.5, black carbon and NO2 and prevalence of current rhinitis in French adults: The Constances Cohort

BACKGROUND

Rhinitis is one of the most common disease worldwide with a high and increasing prevalence. There is limited knowledge on the link between long-term exposure to air pollution and rhinitis.

OBJECTIVES

We aim to study the associations between long-term exposure to air pollutants and self-reported current rhinitis among adults from Constances, a large French population-based cohort.

METHODS

Current rhinitis was defined at inclusion from questionnaire by the presence of sneezing, runny or blocked nose in the last 12 months without a cold or the flu. Annual concentrations of nitrogen dioxide (NO₂), particulate matter ≤ 2.5 µm (PM_2.5) and black carbon (BC) were estimated at the participants' residential address by European land-use regression models. Cross-sectional associations between annual exposure to each air pollutant and current rhinitis were estimated using logistic models adjusted for age, sex, smoking, education level and French deprivation index. The health prevention centers were taken into account by marginal models with generalized estimating equations. Several supplementary analyses were performed.

RESULTS

Analyses were performed on 127,108 participants (47 years old on average, 54% women, 19% current smokers). The prevalence of current rhinitis, allergic (AR) and non-allergic (NAR) rhinitis were 36%, 25% and 11% respectively. Adjusted ORs for current rhinitis were 1.13 (1.08, 1.17), 1.12 (1.07, 1.17), and 1.11 (1.06, 1.17) per one interquartile range increase of PM_2.5 (4.85 µg/m³), BC (0.88 · 10^-5 m^-1) and NO₂ (17.3 µg/m³) respectively. Significant and positive associations were also found for both AR and NAR. Results were similar in men and women, and in the different smoking strata, and were consistent with meta-analysis or after imputing missing covariates.

DISCUSSION

An increase of modeled annual average residential exposure to PM_2.5, BC, and NO₂ was significantly associated with an increase of prevalence of current rhinitis in adults in the French general population. The results suggest that among air pollutants, BC may be of special interest.

Effects of the implementation of a mass rapid transit system on mortality rates attributed to cardiorespiratory complications in Taipei

Although Taipei City has encountered a fall in ambient air pollutant levels since 1996, the year its mass rapid transit (MRT) system commenced operation, no apparent study investigated changes in risks of death attributed to respiratory, cardiovascular, and cerebrovascular diseases in Taipei during this 23-year period. In order to examine the relationship between MRT and occurrence of respiratory and cardiovascular illnesses attributed to air contaminants, exposure over the 23 year duration was subdivided into the following periods: reference period 1 (1992-1995); period 2 (1996-2004), a time when there was a total track length of 67 km; period 3 (2005-2015), when the total track length was lengthened to 131.1 km; and period 4 (2016-2020), when it was further extended to 146.2 km. Taichung City, no MRT system, was used as an external reference population. The effect of Taipei's MRT system on rates of cause-specific death rates was analyzed using robust generalized Poisson regression models. After adjusting for age-standardized rates (ASRs), a decrease in relative risks (RRs) was found for non-trauma death and respiratory disease from periods 2 to 4. Even though the RRs were greater than 1.0 for cardiovascular and cerebrovascular diseases for periods 2 to 4, a downward trend was still noted in these RRs in Taipei. These findings suggest a relationship exists between air pollutant exposure and mortality. In addition, data demonstrated that implementation of the MRT in Taipei exerted beneficial health effects as evidenced by lower mortality rates.

Contributions of internal emissions to peaks and incremental indoor PM2.5 in rural coal use households

Indoor air quality is critically important to the human as people spend most time indoors. Indoor PM_2.5 is related to the outdoor levels, but more directly influenced by internal sources. Severe household air pollution from solid fuel use has been recognized as one major risk for human health especailly in rural area, however, the issue is significantly overlooked in most national air quality controls and intervention policies. Here, by using low-cost sensors, indoor PM_2.5 in rural homes burning coals was monitored for ~4 months and analyzed for its temporal dynamics, distributions, relationship with outdoor PM_2.5, and quantitative contributions of internal sources. A bimodal distribution of indoor PM_2.5 was identified and the bimodal characteristic was more significant at the finer time resolution. The bimodal distribution maxima were corresponding to the emissions from strong internal sources and the influence of outdoor PM_2.5, respectively. Indoor PM_2.5 was found to be correlated with the outdoor PM_2.5, even though indoor coal combustion for heating was thought to be predominant source of indoor PM_2.5. The indoor-outdoor relationship differed significantly between the heating and non-heating seasons. Impacts of typical indoor sources like cooking, heating associated with coal use, and smoking were quantitatively analyzed based on the highly time-resolved PM_2.5. Estimated contribution of outdoor PM_2.5 to the indoor PM_2.5 was ~48% during the non-heating period, but decreased to about 32% during the heating period. The contribution of indoor heating burning coals comprised up to 47% of the indoor PM_2.5 during the heating period, while the other indoor sources contributed to ~20%. The study, based on a relatively long-term timely resolved PM_2.5 data from a large number of rural households, provided informative results on temporal dynamics of indoor PM_2.5 and quantitative contributions of internal sources, promoting scientific understanding on sources and impacts of household air pollution.

WITHDRAWN: Medical assurance system under reliability theory and countermeasures to public health risks

Ahead of Print article withdrawn by publisher.

Allergic symptoms in association with naturalness, greenness, and greyness: A cross-sectional study in schoolchildren in the Alps

BACKGROUND

Greenness may protect from or contribute to allergy risk by influencing air pollution and human-microbe interactions. However, existing research on the issue is heterogeneous and produced conflicting results. Less in known about the effects of greyness. This study investigated the association between different characteristics of residential and school environment and allergic symptoms in schoolchildren.

METHODS

The present cross-sectional survey was undertaken in 2004/2005 among 1251 schoolchildren (8-12 years old) in several alpine valleys in Austria and Italy. Children's mothers completed a questionnaire that asked about allergic symptoms (International Study of Asthma and Allergies in Childhood questionnaire), sociodemographic information, lifestyle, perinatal data, and housing conditions. We constructed four aggregate outcome variables: current asthma symptoms, ever asthma symptoms, ever allergic rhinitis (AR) symptoms, and ever eczema symptoms. We employed well-known greenness and greyness exposure indicators (Normalized Difference Vegetation Index, tree canopy cover, agricultural cover, imperviousness cover, and industrial cover), as well as an alternative naturalness index (Distance to Nature, D2N). Adjusted logistic regressions were used to explore associations between each exposure-outcome pair. Air pollution (NO₂), traffic noise and time spent outdoors were tested as potential mediators in causal mediation analysis.

RESULTS

Decrease in naturalness in a 500-m buffer around the home was associated with higher prevalence of AR symptoms. Associations with asthma symptoms were in the same direction but marginally significant. Residential NDVI and tree cover were marginally associated with lower prevalence of asthma and AR symptoms. Having a domestic garden was associated with lower prevalence of asthma symptoms. School greenness in a 100-m buffer was associated with lower prevalence of AR symptoms. Residential greyness was associated with higher prevalence of AR and asthma symptoms. We observed stronger associations for greenness and greyness in non-movers and in children without a family history of allergies. Mediation by NO₂ and time spent outdoors was present in some of the exposure-outcome pairs.

CONCLUSIONS

Schoolchildren residing in places with lower naturalness and higher greyness may be more likely to have allergic rhinitis and possibly asthma. Considering more comprehensive indicators than greenness and greyness and conducting research in children without a family history of allergic diseases may be key to better understanding who can profit from natural landscapes.

E-cigarette Solvent Ratio and Device Power Influence Ambient Air Particulate Matter

OBJECTIVES

Electronic cigarette (ECIG)-generated aerosol contains particulate matter with a diameter less than 2.5 microns (PM2.5). Particles of this size may be injurious to the health of those who inhale them. Few studies have assessed the relationship between ECIG aerosol PM2.5 and ECIG liquid ingredients or ECIG device power.

METHODS

Two studies were conducted in which participants generated aerosols with ECIGs: in one, ECIG liquids contained various vegetable glycerin/propylene glycol ratios and in the other, ECIG devices varied by electrical power output.

RESULTS

Results indicate that, in general, PM2.5 increases as the ratio of vegetable glycerin to propylene glycol increases, or as device power increases.

CONCLUSIONS

Regulating ECIG PM2.5 emissions to protect non-users requires an understanding of all the factors that influence these emissions.

Elevated levels of nitrous dioxide are associated with lower AMH levels: a real-world analysis

STUDY QUESTION

Are there any associations between environmental pollutants and ovarian reserve, expressed by anti-Mullerian hormone (AMH) serum levels?

SUMMARY ANSWER

In this first real-world approach to demonstrate the relationship between air pollutants and serum AMH levels, adverse associations were observed for nitrogen dioxide (NO2) but not with particulate matter.

WHAT IS KNOWN ALREADY

In recent years, air pollution has emerged as a potential disrupter to the homeostasis of physiological hormones, possibly affecting human reproduction. Although the influence of age and smoking on AMH levels is largely accepted, the relationship between AMH and the environment has not currently been established.

STUDY DESIGN, SIZE, DURATION

A longitudinal, observational, retrospective, real-world study was carried out, including all AMH measurements performed in a single laboratory from January 2007 to October 2017.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Serum AMH data were connected to patients' age and residential address, to include air pollution data after geo-localisation. The air pollution considered daily particulate matter (PM) and NO2 values.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 1463 AMH measurements were collected (mean 1.94 ng/ml, median 0.90 ng/ml). AMH was inversely related to patients' age in women older than 25 years (adjusted R-squared 0.120, P < 0.001), but not in those younger than 25 years (adjusted R-squared 0.068, P = 0.055). AMH levels were inversely related to environmental pollutants, such as PM10 (Rho = -0.088, P = 0.001), PM2.5 (Rho = -0.062, P = 0.021) and NO2 (Rho = -0.111, P < 0.001). After subdividing the dataset into quartiles for PM10 and PM2.5, the influence of age on AMH serum levels was found to be a stronger influence than that exerted by PM (P = 0.833 and P = 0.370, respectively). On the contrary, considering NO2 quartiles, higher AMH levels were observed in third quartile compared to fourth quartile, even after adjustment for age (P = 0.028), indicating a stronger influence of NO2 exposure on AMH serum levels. Considering an AMH cut-off of 0.3 ng/ml, a significant higher frequency of women with severe ovarian reserve reduction in the fourth quartile was shown only for NO2 (P = 0.010).

LIMITATIONS, REASONS FOR CAUTION

Several limitations should be underlined, such as the lack of information about work and life habits of each patient and the retrospective nature of the analysis performed on real-world data.

WIDER IMPLICATIONS OF THE FINDINGS

Although the genetic component is highly predictive for defining the ovarian reserve at birth, potentially modifiable environmental factors could influence the rate of decline in AMH and ovarian reserve during adulthood.

STUDY FUNDINGCOMPETING INTEREST(S)

Authors have neither funding nor competing interests to declare.

TRIAL REGISTRATION NUMBER

N/A.

Joint association of cigarette smoking and PM2.5 with COPD among urban and rural adults in regional China

Background

Cigarette smoking and PM_2.5 are important risk factors of Chronic Obstructive Pulmonary Disease (COPD). However, the joint association of cigarette smoking and PM_2.5 with COPD is unknown.

Methods

A community-based study was conducted among urban and rural adults aged 40 + years between May and December of 2015 in Jiangsu Province, China. The outcome variable was spirometry-defined COPD. Explanatory measures were smoking status (non-smokers or smokers) and PM_2.5 exposure [low level (< 75 μg/m³) or high level (≥ 75 μg/m³)]. Mixed-effects logistic regression models were applied to calculate the odds ratio (OR) and 95% confidence interval (CI) to investigate the associations of cigarette smoking and PM_2.5 with COPD.

Results

The prevalence of COPD was 11.9% (95% CI = 10.9%, 13.0%) within the overall 3407 participants in this study. After adjustment for potential confounders and community-level clustering effect, smokers tended to develop COPD relative to non-smokers (OR = 2.46, 95% CI 1.76, 3.43), while only smokers exposed to high level PM_2.5 were more likely to experience COPD (OR = 1.36; 95% CI 1.01, 1.83) compared to their counterparts exposed to low level PM_2.5. Meanwhile, compared to non-smokers who exposed to low level PM_2.5, non-smokers who exposed to high level PM_2.5 (OR = 1.10, 95% CI 0.74, 1.64), smokers who exposed to low (OR = 2.22, 95% CI 1.51, 3.27) or high level PM_2.5 (OR = 3.14, 95% CI 2.15, 4.59) were, respectively, more like to develop COPD.

Conclusions

Cigarette smoking was positively associated with COPD among overall participants, while PM_2.5 was in positive relation to COPD among smokers only. Moreover, cigarette smoking and PM_2.5 might have an additive effect on the risk of COPD among adult smokers aged 40 years or older in China.

Addictions in the COVID-19 era: Current evidence, future perspectives a comprehensive review

BACKGROUND

In the context of the COVID-19 worldwide pandemic, an up-to-date review of current challenges in addictions is necessary. While large scale disasters may have an impact on substance use and addictions, the use of some substances is also likely to modify the risk of COVID-19 infection or course. Many countries have imposed lockdowns. Whether this quarantine or the end of lockdown measures will have an impact on substance use is discussed. The aim of this review is to gather knowledge for clinicians and to guide public health policies during/after lockdown.

METHODS

PubMed was reviewed in August 6th (2020), to determine the current evidences and observations concerning the addictions and SARS-CoV2. We used all the names of the severe acute respiratory syndrome of coronavirus 2 (SARS-CoV2 previously 2019 nCoV), the name of the coronavirus disease 2019 (COVID-19), and common substances of abuse. For the physiopathological parts, searches were conducted using key words such as "infection" or "pneumonia". For the lockdown effects, key words such as "quarantine", "disaster" or "outbreak" were used.

RESULTS

Overall, pathophysiological data showed an increased risk of infections for individuals with Substance Use Disorders (SUD) and a possible protective role of nicotine. During lockdown, there is a substantial risk of increasing SUDs. Individuals with opioid use disorder are particularly at risk of relapse or of involuntary withdrawal. After lockdown, increase of use may be observed as far as years after. Individuals with addictions are at higher risk of multimorbidity and mortality during COVID outbreak.

CONCLUSION

This review describes useful strategies in clinical practice, including a systematic assessment of addiction comorbidity during this almost worldwide lockdown/pandemic. This review also highlights important areas for future research.

Environmental toxicology wars: Organ-on-a-chip for assessing the toxicity of environmental pollutants

Environmental pollution is a widespread problem, which has seriously threatened human health and led to an increase of human diseases. Therefore, it is critical to evaluate environmental pollutants quickly and efficiently. Because of obvious inter-species differences between animals and humans, and lack of physiologically-relevant microenvironment, animal models and in vitro two-dimensional (2D) models can not accurately describe toxicological effects and predicting actual in vivo responses. To make up the limitations of conventional environmental toxicology screening, organ-on-a-chip (OOC) systems are increasingly developing. OOC systems can provide a well-organized architecture with comparable to the complex microenvironment in vivo and generate realistic responses to environmental pollutants. The feasibility, adjustability and reliability of OCC systems make it possible to offer new opportunities for environmental pollutants screening, which can study their metabolism, collective response, and fate in vivo. Further progress can address the challenges to make OCC systems better investigate and evaluate environmental pollutants with high predictive power.

A novel model for regional indoor PM2.5 quantification with both external and internal contributions included

PM_2.5 (particulate matter with an aerodynamic size ≤ 2.5 μm) of indoor origins is a dominant contributor to the overall air pollution exposure. Although some sophisticated models have been developed to simulate indoor air quality for individual households, it is still challenging to quantify indoor PM_2.5 on a regional scale, which is critical for health impact assessments. In this study, a new model was developed to predict indoor PM_2.5 concentrations by quantifying the external penetration, as well as the internal contributions. The model was parameterized based on a set of simultaneously measured indoor and outdoor PM_2.5 concentrations at five-second temporal resolution for 53 households in Beijing. This study found that indoor PM_2.5 concentrations were significantly correlated with those in the outdoor environment with an approximately 1-h lag-time on average. Outdoor-to-indoor penetration dominated the contribution to indoor PM_2.5 during polluted hours with relatively high ambient PM_2.5 concentrations, while the indoor PM_2.5, during clean hours, was contributed by internal sources, including smoking, cooking, incense burning, and human disturbance. The influence of windows, house area, and air purifier use was addressed in the new model. The model was applied to evaluate indoor PM_2.5 concentrations in six urban districts of Beijing via an uncertainty analysis. The model was developed based on and applied to households using clean residential energy, and it would be interesting also important to evaluate it in households using solid fuels.

A novel lncRNA, loc107985872, promotes lung adenocarcinoma progression via the notch1 signaling pathway with exposure to traffic-originated PM2.5 organic extract

PM2.5 pollution is an important and urgent problem in China that can increase mortality and hospital admissions. Traffic-originated PM2.5 organic component (tPo) mainly contains polycyclic aromatic hydrocarbons (PAHs). Research has shown that PAHs can promote invasion, metastasis, and cancer stem cell properties in lung adenocarcinoma cells, but the exact toxicological mechanism is unknown. In the present study, we investigated the effect of lncRNAs on the progression of lung adenocarcinoma induced by tPo and the underlying mechanisms mediated by lncRNA-signaling pathway interactions. We found that chronic tPo treatment upregulated the expression of loc107985872, which further promoted cell invasion and migration, EMT and cancer stem cell properties via notch1 pathway in lung adenocarcinoma cells. Meanwhile, activation of the notch1 signaling pathway through loc107985872 might be associated with abnormally high expression of its upstream proteins, such as ADAM17, PSEN1 and DLL1. Moreover, tPo exposure induced EMT and the acquisition of cancer stem cell-like properties via the notch1 signaling pathway in vivo. In summary, loc107985872 upregulated by tPo promoted lung adenocarcinoma progression via the notch1 signaling pathway.

Biomarkers and indoor air quality: A translational research review

Introduction:

Air pollution is linked to mortality and morbidity. Since humans spend nearly all their time indoors, improving indoor air quality (IAQ) is a compelling approach to mitigate air pollutant exposure. To assess interventions, relying on clinical outcomes may require prolonged follow-up, which hinders feasibility. Thus, identifying biomarkers that respond to changes in IAQ may be useful to assess the effectiveness of interventions.

Methods:

We conducted a narrative review by searching several databases to identify studies published over the last decade that measured the response of blood, urine, and/or salivary biomarkers to variations (natural and intervention-induced) of changes in indoor air pollutant exposure.

Results:

Numerous studies reported on associations between IAQ exposures and biomarkers with heterogeneity across study designs and methods. This review summarizes the responses of 113 biomarkers described in 30 articles. The biomarkers which most frequently responded to variations in indoor air pollutant exposures were high sensitivity C-reactive protein (hsCRP), von Willebrand Factor (vWF), 8-hydroxy-2′-deoxyguanosine (8-OHdG), and 1-hydroxypyrene (1-OHP).

Conclusions:

This review will guide the selection of biomarkers for translational studies evaluating the impact of indoor air pollutants on human health.

How Do Combustion and Non-Combustion Products Used Outdoors Affect Outdoor and Indoor Particulate Matter Levels? A Field Evaluation Near the Entrance of an Italian University Library

Particulate Matter (PM) is a well-known health risk factor and pollutes both outdoor and indoor air. Using PM as an air pollution indicator, the aims were to assess outdoor and indoor air pollution due to combustion and/or non-combustion products used outdoors and to compare the PM levels emitted by different products. PM with an aerodynamic diameter ≤10, 4, 2.5 and 1 µm (PM₁₀, PM₄, PM_2.5, PM₁) was simultaneously measured in two areas, respectively, indoors (with smoking ban) and outdoors (where people commonly smoke) of a university library during the morning and the afternoon of two weekdays. Both combustion and non-combustion products determined a relevant worsening of outdoor air quality, with the highest PM₁ levels achieved when a single traditional cigarette (9920 µg m^-3), a single e-cigarette (9810 µg m^-3) and three simultaneous traditional cigarettes (8700 µg m^-3) were smoked. An increase of indoor PM₁ levels was found during outdoor smoking/vaping sessions, persisting also after the end of sessions. The results highlighted the need for a revision of smoke-free laws, especially for outdoor areas, to include non-combustion products. In addition, it is essential to make society aware of the dangers of smoking outdoors by implementing health promotion interventions.