Air Pollution and Occupational Exposure

Environmentally persistent free radicals (EPFRs) are a kind of hazardous substance that exist stably in the atmosphere for a long time. EPFRs combined with fine particulate matter (PM_2.5) can enter the human respiratory tract through respiration, causing oxidative stress and DNA damage, and they are also closely related to lung cancer. In this study, the inhalation risk for EPFRs in PM_2.5 and factors influencing this risk were assessed using the equivalent number of cigarette tar EPFRs. The daily inhalation exposure for EPFRs in PM_2.5 was estimated to be equivalent to 0.66–8.40 cigarette tar EPFRs per day. The concentration level and species characteristics were investigated using electron paramagnetic resonance spectroscopy. The concentration of EPFRs in the study ranged from 1.353–4.653 × 10¹³ spins/g, and the types of EPFRs were mainly oxygen- or carbon-centered semiquinone-type radicals. Our study showed that there is a strong correlation between the concentrations of EPFRs and conventional pollutants, except for sulfur dioxide. The major factors influencing EPFR concentration in the atmosphere were temperature and wind speed; the higher the temperature and wind speed, the lower the concentration of EPFRs. The findings of this study provide an important basis for further research on the formation mechanism and health effects of EPFRs. Full article

Background: Pesticides manage pests and diseases in agriculture, but they harm the health of agricultural workers. Concentrations of thirteen pesticides were determined in personal air and blood serum of 85 paddy farmers and 85 non-farmers, thereafter associated with health symptoms. Method: Samples were analyzed using ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Results: The median concentration of pesticides in personal air samples ranged from 10.69 to 188.49 ng/m³ for farmers and from 5.79 to 73.66 ng/m³ for non-farmers. The median concentration of pesticides in blood serum was from 58.27 to 210.12 ng/mL for farmers and 47.83 to 62.74 ng/mL for non-farmers. Concentration of eleven pesticides in personal air and twelve pesticides in blood serum were significantly higher in farmers than non-farmers (p < 0.05). All pesticides detected in personal air correlated significantly with concentration in the blood serum of farmers (p < 0.05). Health symptoms reported by farmers were dizziness (49.4%), nausea (47.1%), cough (35.3%), chest pain (30.6%), breathing difficulty (23.5%), sore throat (22.4%), vomiting (18.8%), phlegm (16.5%), and wheezing (15.3%). Concentration of pesticides in personal air, blood serum, and health symptoms were not significantly associated. Conclusion: Occupational exposure to pesticides significantly contaminates blood serum of farmers compared to non-farmers. Full article

Haze occurred in Zhengzhou, a megacity in the northern China, with the PM_2.5 as high as 254 μg m⁻³ on 25 December 2019, despite the emergency response measure of restriction on the emission of anthropogenic pollutants which was implemented on December 19 for suppressing local air pollution. Air pollutant concentrations, chemical compositions, and the origins of particulate matter with aerodynamic diameter smaller than 2.5 µm (PM_2.5) between 5–26 December were investigated to explore the reasons for the haze occurrence. Results show that the haze was caused by efficient SO₂-to-suflate and NO_x-to-nitrate conversions under high relative humidity (RH) condition. In comparison with the period before the restriction (5–18 December) when the PM_2.5 was low, the concentration of PM_2.5 during the haze (19–26 December) was 173 µg m⁻³ on average with 51% contributed by sulfate (31 µg m⁻³) and nitrate (57 µg m⁻³). The conversions of SO₂-to-sulfate and NO_x-to-nitrate efficiently produced sulfate and nitrate although the concentration of the two precursor gases SO₂ and NO_x was low. The high RH, which was more than 70% and the consequence of artificial water-vapor spreading in the urban air for reducing air pollutants, was the key factor causing the conversion rates to be enlarged in the constriction period. In addition, the last 48 h movement of the air parcels on 19–26 December was stagnant, and the air mass was from surrounding areas within 200 km, indicating weather conditions favoring the accumulation of locally-originated pollutants. Although emergency response measures were implemented, high gas-to-particle conversions in stagnant and moisture circumstances can still cause severe haze in urban air. Since the artificial water-vapor spreading in the urban air was one of the reasons for the high RH, it is likely that the spreading had unexpected side effects in some certain circumstances and needs to be taken into consideration in future studies. Full article

Epidemiologic studies have suggested an association between agrochemical exposure and risk of renal injury. Farmers face great risks to developing adverse effects. The most appropriate biomarker related to renal injury needs to be developed to encounter earlier detection. We aim to study the association between early renal biomarker and occupational herbicide exposure in maize farmers, Thailand. Sixty-four farmers were recruited and interviewed concerning demographic data, herbicide usage, and protective behavior. Two spot urines before (pre-work task) and after (post-work task) herbicide spraying were collected. To estimate the intensity of exposure, the cumulative herbicide exposure intensity index (cumulative EII) was also calculated from activities on the farm, type of personal protective equipment (PPE) use, as well as duration and frequency of exposure. Four candidate renal biomarkers including π-GST, sirtuin-1, mitochondrial DNA (mtDNA) were measured. Most subjects were male and mostly sprayed three herbicides including glyphosate-based herbicides (GBH), paraquat, and 2,4-dichlorophenoxyacetic acid (2,4-D). A type of activity in farm was mixing and spraying herbicide. Our finding demonstrated no statistical significance of all biomarker levels between pre- and post-work task urine. To compare between single and cocktail use of herbicide, there was no statistical difference in all biomarker levels between pre- and post-work task urine. However, the urinary mtDNA seems to be increased in post-work task urine. Moreover, the cumulative EII was strongly associated with change in mtDNA content in both ND-1 and COX-3 gene. The possibility of urinary mtDNA as a valuable biomarker was promising as a noninvasive benchmark for early detection of the risk of developing renal injury from herbicide exposure. Full article

The level and composition of air pollution have changed during the coronavirus disease 2019 (COVID-19) pandemic. However, the association between air pollution and pediatric respiratory disease emergency department (ED) visits during the COVID-19 pandemic remains unclear. The study was retrospectively conducted between 2017 and 2020 in Kaohsiung, Taiwan, from 1 January 2020 to 1 May 2020, defined as the period of the COVID-19 pandemic, and 1 January 2017 to 31 May 2019, defined as the pre-COVID-19 pandemic period. We enrolled patients under 17 years old who visited the ED in a medical center and were diagnosed with respiratory diseases such as pneumonia, asthma, bronchitis, and acute pharyngitis. Measurements of particulate matter (PM) with aerodynamic diameters of <10 μm (PM₁₀) and < 2.5 μm (PM_2.5), nitrogen dioxide (NO₂), and Ozone (O₃) were collected. During the COVID-19 pandemic, an increase in the interquartile range of PM_2.5, PM₁₀, and NO₂ levels was associated with increases of 72.5% (95% confidence interval [CI], 50.5–97.7%), 98.0% (95% CI, 70.7–129.6%), and 54.7% (95% CI, 38.7–72.6%), respectively, in the risk of pediatric respiratory disease ED visits on lag 1, which were greater than those in the pre-COVID-19 pandemic period. After adjusting for temperature and humidity, the risk of pediatric respiratory diseases after exposure to PM_2.5 (inter p = 0.001) and PM₁₀ (inter p < 0.001) was higher during the COVID-19 pandemic. PM_2.5, PM₁₀, and NO₂ may play important roles in pediatric respiratory events in Kaohsiung, Taiwan. Compared with the pre-COVID-19 pandemic period, the levels of PM_2.5 and PM₁₀ were lower; however, the levels were related to a greater increase in ED during the COVID-19 pandemic. Full article

In this study, the emission factor and concentration of ammonia from industrial waste incineration facilities were analyzed through actual measurements. The ammonia emission factor was calculated and the difference in ammonia emission factor for each type of incineration was confirmed through the Mann–Whitney U test. As a result of analyzing 279 samples, the NH₃ emission factor of the SNCR facility of stoker types was 0.012 kgNH₃/ton, and the NH₃ emission factor of the SNCR facility of the rotary kiln methods was 0.014 kgNH₃/ton. Additionally, the NH₃ emission factor of this study was higher than the NH₃ emission factor (0.003 kgNH₃/ton) suggested by Kang’s study (0.009 kgNH₃/ton) and EMEP/EEA (2006). There is a need to develop an NH₃ emission factor that takes into account the characteristics of Korea, since it is largely different from the NH₃ emission factor of EMEP/EEA. As a result of statistical analysis of the stoker type and the rotary kiln method, the null hypothesis that there is no difference between each type was adopted (p-value > 0.05), indicating that there was no statistical difference in the ammonia emission factors of the stoker type and the rotary kiln type. Full article

With the intensification of global warming and economic development in China, the near-surface ozone (O₃) concentration has been increasing recently, especially in the Beijing-Tianjin-Hebei (BTH) region, which is the political and economic center of China. However, O₃ has been measured in real time only over the past few years, and the observational records are discontinuous. Therefore, we propose a new method (WRFC-XGB) to establish a near-surface O₃ concentration dataset in the BTH region by integrating the Weather Research and Forecasting with Chemistry (WRF-Chem) model with the extreme gradient boosting (XGBoost) algorithm. Based on this method, the 8-h maximum daily average (MDA8) O₃ concentrations are obtained with full spatiotemporal coverage at a spatial resolution of 0.1° × 0.1° across the BTH region in 2018. Two evaluation methods, sample- and station-based 10-fold cross-validation (10-CV), are used to assess our method. The sample-based (station-based) 10-CV evaluation results indicate that WRFC-XGB can achieve excellent accuracy with a high coefficient of determination (R²) of 0.95 (0.91), low root mean square error (RMSE) of 13.50 (17.70) µg m⁻³, and mean absolute error (MAE) of 9.60 (12.89) µg m⁻³. In addition, superb spatiotemporal consistencies are confirmed for this model, including the estimation of high O₃ concentrations, and our WRFC-XGB model outperforms traditional models and previous studies in data mining. In addition, the proposed model can be applied to estimate the O₃ concentration when it has not been measured. Furthermore, the spatial distribution analysis of the MDA8 O₃ in 2018 reveals that O₃ pollution in the BTH region exhibits significant seasonality. Heavy O₃ pollution episodes mainly occur in summer, and the high O₃ loading is distributed mainly in the southern BTH areas, which will pose challenges to atmospheric environmental governance for local governments. Full article

The burning of crop residue in the open field has become a significant concern for climate change mitigation efforts worldwide. This practice has led to air quality impairment, smog, haze, heat waves, and different health problems. These could be avoided by adopting sustainable crop residue management practices (SCRMPs) and enabling farmers to engage in SCRMPs. Assessing the health effects at the household level is critical for understanding this problem and finding a solution. Using the primary dataset of 420 farmers from Punjab, Pakistan, we estimated the incurred impacts and costs of crop residue burning. We calculated the health and environmental benefits associated with adopting SCRMPs by comparing the two groups of farmers (adopters and non-adopters). Furthermore, we used a propensity score matching technique to measure the causal impact of SCRMPs adoption on health costs. The findings showed that a surprisingly large number of farmers are all aware of the adverse effects of residue burning, and many do not burn crop residues and instead use SCRMPs. This study found that households with chronic and non-chronic diseases become acute, and the severity increases during the burning period. They spend USD 13.37 to USD 8.79 on chronic and non-chronic diseases during the burning season, respectively. Consequently, the use of SCRMPs has a positive effect on healthcare costs. Our study findings highlight the meaningful implications for developing a new policy to promote the sustainable utilization of crop residues and enhance their adoption in Pakistan. Full article

Introduction: Vietnamese nail salon technicians are continuously exposed to neurotoxins linked to cognitive impairments and Alzheimer’s disease. This study examined the association of occupational exposure with cognitive function and depressive symptoms among Vietnamese nail salon technicians. Methods: The sample included 155 current or former Vietnamese female nail technicians and 145 control group participants. Measures included the Montreal Cognitive Assessment (MoCA) and the Center for Epidemiologic Studies Depression Scale (CES-D). Results: Average cognitive functioning was significantly higher for the control compared to the nail technician group (mean difference = 1.2, p < 0.05). No differences were observed for depression. Multivariate findings revealed that exposure was negatively associated with cognitive functioning (β = −0.29, 95% CI: −0.53, −0.05, p < 0.05). Discussion: Nail salon work and the extent of occupational exposure were associated with lower cognitive functioning among Vietnamese nail technicians. Longitudinal research can further examine the risk for cognitive decline and dementia for this vulnerable population. Full article

Exploring the spatial and temporal distribution characteristics of air quality has become an important topic for the harmonious development of human and nature. Based on the hourly data of CO, O₃, NO₂, SO₂, PM_2.5 and PM₁₀ of 1427 air quality monitoring stations in China in 2016, this paper calculated the annual mean and annual standard deviation of six air quality indicators at each station to obtain 12 variables. Self-Organizing Maps (SOM) and K-means clustering algorithms were carried out based on MATLAB and SPSS Statistics, respectively. Kriging interpolation was used to get the clustering distribution of air quality and fluctuation in China, and Principal Component Analysis (PCA) was used to analyze the main factors affecting the clustering results. The results show that: (1) Most areas in China are low-value regions, while the high-value region is the smallest and more concentrated. Air quality in northern China is worse, and the annual fluctuations of the indicators are more dramatic. (2) Compared with AQI, AQFI has a strong indication significance for the comprehensive situation of air quality and its fluctuation. (3) The spatial distribution of SOM clustering results is more discriminative, while K-means clustering results have a large proportion of low-mean regions. (4) PM_2.5, PM₁₀ and CO are the main pollutants affecting air quality and fluctuation, followed by SO₂, NO₂ and O₃. Full article

Studies on droplet transmission are needed to understand the infection mechanism of SARS-CoV-2. This research investigated the effects of coughing intensity and wind direction on respiratory droplets transportation using the Euler–Lagrange method. The results revealed that both coughing intensity and wind conditions considerably influence the transmission of small and medium droplets but had little effect on large droplets. A stronger coughing intensity resulted in small and medium droplets traveling farther in a calm wind and spreading widely and rapidly in a windy environment. The droplets do not travel far in the absence of ambient wind, even with stronger coughing. Medium droplets spread in clusters, and small droplets drifted out of the domain in the band area in different wind conditions except for 60° and 90° wind directions, in which cases, the droplets were blown directly downstream. In 0° wind direction, many droplets were deposited on the human body. The fast and upward movement of particles in 60° and 90° directions could cause infection risk with short exposure. In 180° wind direction, droplets spread widely and traveled slowly because of the reverse flow downstream, prolonged exposure can result in a high risk of infection. Full article

We aimed to identify the variables that modify levels of oxidatively damaged DNA and lipid peroxidation in subjects living in diverse localities of the Czech Republic (a rural area, a metropolitan locality, and an industrial region). The sampling of a total of 126 policemen was conducted twice in two sampling seasons. Personal characteristics, concentrations of particulate matter of aerodynamic diameter <2.5 µm and benzo[a]pyrene in the ambient air, activities of antioxidant mechanisms (superoxide dismutase, catalase, glutathione peroxidase, and antioxidant capacity), levels of pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6), concentrations of persistent organic pollutants in blood plasma, and urinary levels of polycyclic aromatic hydrocarbon metabolites were investigated as parameters potentially affecting the markers of DNA oxidation (8-oxo-7,8-dihydro-2′-deoxyguanosine) and lipid peroxidation (15-F2t-isoprostane). The levels of oxidative stress markers mostly differed between the localities in the individual sampling seasons. Multivariate linear regression analysis revealed IL-6, a pro-inflammatory cytokine, as a factor with the most pronounced effects on oxidative stress parameters. The role of other variables, including environmental pollutants, was minor. In conclusion, our study showed that oxidative damage to macromolecules was affected by processes related to inflammation; however, we did not identify a specific environmental factor responsible for the pro-inflammatory response in the organism. Full article

Previous studies have described the chemical pollution in indoor air of healthcare and care facilities. From these studies, the main objective of this work was to conduct a quantitative health risk assessment of the chronic inhalation of chemical compounds by workers in healthcare and elderly care facilities (hospitals, dental and general practitioner offices, pharmacies and nursing homes). The molecules of interest were 36 volatile and 13 semi-volatile organic compounds. Several professional exposure scenarios were developed in these facilities. The likelihood and severity of side effects that could occur were assessed by calculating the hazard quotient for deterministic effects, and the excess lifetime cancer risk for stochastic effects. No hazard quotient was greater than 1. Three compounds had a hazard quotient above 0.1: 2-ethyl-1-hexanol in dental and general practitioner offices, ethylbenzene and acetone in dental offices. Only formaldehyde presented an excess lifetime cancer risk greater than 1 × 10⁻⁵ in dental and general practitioner offices (maximum value of 3.8 × 10⁻⁵ for general practitioners). The health risk for chronic inhalation of most compounds investigated did not appear to be of concern. Some values tend to approach the acceptability thresholds justifying a reflection on the implementation of corrective actions such as the installation of ventilation systems. Full article

Particulate matter with a diameter of ≤10 µm (PM₁₀) and nitrogen dioxide (NO₂) affect the DNA methylation in the fetus, but epigenetic studies regarding prenatal exposure to air pollution in Asia are lacking. Therefore, this study aimed to assess whether there is any association between the ambient concentrations of PM₁₀ and NO₂ and CpG methylation in the cord blood DNA by using a Korean birth cohort. The concentrations of the air pollutants were incorporated into the final LUR model by using the maternal address data. The methylation level was determined using HumanMethylationEPIC BeadChip and a linear regression analysis model. A multipollutant model including both PM₁₀ and NO₂ and models with single pollutants were used for each trimester exposure. The number of differentially methylated positions was the largest for midpregnancy exposure in both the single pollutant models and the multipollutant regression analysis. Additionally, gene-set analysis regarding midpregnancy exposure revealed four gene ontology terms (cellular response to staurosporine, positive regulation of cytoskeleton organization, neurotransmitter transport, and execution phase of apoptosis). In conclusion, these findings show an association between prenatal PM₁₀ and NO₂ exposure and DNA methylation in several CpG sites in cord blood cells, especially for midpregnancy exposure. Full article

Air pollution exposure has become ubiquitous and is increasingly detrimental to human health. Small Particulate matter (PM) is one of the most harmful forms of air pollution. It can easily infiltrate the lungs and trigger several respiratory diseases, especially in vulnerable populations such as children and elderly people. In this work, we start by leveraging a retrospective study of 416 children suffering from respiratory diseases. The study revealed that asthma prevalence was the most common among several respiratory diseases, and that most patients suffering from those diseases live in areas of high traffic, noise, and greenness. This paved the way to the construction of the MOREAIR dataset by combining feature abstraction and micro-level scale data collection. Unlike existing data sets, MOREAIR is rich in context-specific components, as it includes 52 temporal or geographical features, in addition to air-quality measurements. The use of Random Forest uncovered the most important features for the understanding of air-quality distribution in Moroccan urban areas. By linking the medical data and the MOREAIR dataset, we observed that the patients included in the medical study come mostly from neighborhoods that are characterized by either high average or high variations of pollution levels. Full article

This study was designed to assess the health impacts related to noninvasive carbon monoxide saturation (SPCO %) in the blood of respondents. For this purpose, 150 respondents from the labour community of Hattar Industrial Estate (testing site) and 100 respondents from Sultan Pur (control site) were selected. To achieve this objective, a Rad-57 Pulse CO-Oximeter was used for noninvasive carboxyhemoglobin measurement. Carbon monoxide saturation (SPCO%) in the blood of respondents from Hattar Industrial Estate, Haripur, Pakistan has been compared with the WHO’s standard concentration of SPCO% (5%). High saturation of carbon monoxide (carboxyhemoglobin SPCO) in the blood of respondents and disease association have been interpreted in graphs formed on the basis of statistical analysis in terms of frequencies, using statistical software (SPSS), based on demographic entries as well as exposure time of the employees in the processing, food and steel industries. The highest SPCO% measured was 17% in the steel industry and the lowest measured level was 4.2%. Frequencies and percentages of respiratory inflammation, dermatosis, asthma, breathing issues and eye inflammation among respondents were 29%, 35%, 16.7%, 23.5% and 9%, respectively. Prevalence of disease in three different groups of respondents (from three testing sites) was also analyzed on the basis of exposure time (hrs.) to carbon monoxide emissions. Prevalence of disease among the exposed and non-exposed groups was analyzed and showed comparatively lower disease prevalence in the group of respondents who were not exposed to high carbon monoxide emissions. The data of the current study was also subjected to statistical modelling to find the health risk of air pollutants (carbon monoxide) on population health by calculating attributable risk (AR) or attributable proportion (AP). Results indicated that attributable risk of carbon monoxide exposure for respiratory diseases, dermatosis and eye inflammation were 61.12%, 65.77% and 24.95% respectively. Findings of statistical modelling indicated that dermatosis and respiratory diseases were more prevalent in laborers of industrial units than those at control site. Full article

Occupational chrysotile asbestos exposure data in Zimbabwe is limited. The aim of this study was therefore to develop a job exposure matrix (JEM) specific to the chrysotile asbestos cement manufacturing industry using the available personal exposure concentration data. Quantitative personal exposure chrysotile fibre concentration data collected by the two factories from 1996 to 2020 were used to construct the JEM. Exposure groups from which data was extracted were classified based on the Zimbabwe Standard Classification of Occupations (ZSCO), 2009–2019. Analysis of amphiboles in raw chrysotile was done by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Descriptive statistics, namely mean, standard deviation and range were computed for the main variable, job/occupation. All jobs/occupations in both factories had annual mean personal exposure concentrations exceeding the OEL of 0.1 f/mL, except for the period from 2009 to 2016 in the Harare factory and the period from 2009 to 2020 in the Bulawayo factory. Despite the Harare factory having no AC manufacturing activity since 2017, personal exposure concentrations showed elevated levels for the period 2018–2020. Amphiboles were detected in almost all bulk samples of chrysotile asbestos analysed. The established JEM, which has been generated from actual local quantitative exposure measurements, can be used in evaluating historical exposure to chrysotile asbestos fibre, to better understand and predict occurrence of ARDs in future. Full article

Considering the multitudes of people who spend their time working indoors in public premises and workplaces, it is worth knowing what their level of exposure is to natural radioactive radon gas, the second most widespread and dangerous carcinogen for lung cancer development after cigarette smoking. This state-level study covered most of the territory of Latvia and conducted 941 radon measurements with Radtrack2, placed for 4–6 months in the premises of public companies, educational institutions, medical care institutions, etc. The study found that 94.7% of samples did not exceed the national permissible limit (200 Bq/m³), the level at which preventive measures should be initiated. The median value of average specific radioactivity of radon in these premises was 48 Bq/m³ (Q1 and Q3 being 27 and 85 Bq/m³), which is below the average of the European region. Slightly higher concentrations were observed in well-insulated premises with plastic windows and poorer air exchange, mostly in schools (59 (36, 109) Bq/m³) and kindergartens (48 (32, 79) Bq/m³). Industrial workplaces had surprisingly low radon levels (28 (16, 55) Bq/m³) due to strict requirements for air quality and proper ventilation. Public premises and workplaces in Latvia mostly have low radon concentrations in the air, but more attention should be paid to adequate ventilation and air exchange. Full article

First responders (FR) exposed to the World Trade Center (WTC) Ground Zero air over the first week after the 9/11 disaster have an increased heart disease incidence compared to unexposed FR and the general population. To test if WTC dusts were causative agents, rats were exposed to WTC dusts (under isoflurane [ISO] anesthesia) 2 h/day on 2 consecutive days; controls received air/ISO or air only. Hearts were collected 1, 30, 240, and 360 d post-exposure, left ventricle total RNA was extracted, and transcription profiles were obtained. The data showed that differentially expressed genes (DEG) for WTC vs. ISO rats did not reach any significance with a false discovery rate (FDR) < 0.05 at days 1, 30, and 240, indicating that the dusts did not impart effects beyond any from ISO. However, at day 360, 14 DEG with a low FDR were identified, reflecting potential long-term effects from WTC dust alone, and the majority of these DEG have been implicated as having an impact on heart functions. Furthermore, the functional gene set enrichment analysis (GSEA) data at day 360 showed that WTC dust could potentially impact the myocardial energy metabolism via PPAR signaling and heart valve development. This is the first study showing that WTC dust could significantly affect some genes that are associated with the heart/CV system, in the long term. Even > 20 years after the 9/11 disaster, this has potentially important implications for those FR exposed repeatedly at Ground Zero over the first week after the buildings collapsed. Full article

This study investigated the concentrations of air pollutants (NO, NO₂, NO_x, SO₂, CO, O₃, PM₁₀, and PM_2.5) at three sites with different traffic loads (work, residential, and traffic sites) before, during, and after the COVID-19 lockdown. The main objective of this study was to evaluate the effects and associated potential pollution control implications of the lockdown on the quality of ambient air at three selected sites in the urban area of Riyadh City. The average concentrations of NO, NO₂, NO_x, and CO decreased during the lockdown period by 73%, 44%, 53%, and 32% at the work site; 222%, 85%, 100%, and 60% at the residential site; and 133%, 60%, 101%, and 103% at the traffic site relative to the pre-lockdown period, respectively. The average concentration of O₃ increased by 6% at the work site, whereas the concentration of SO₂ increased by 27% at the residential site and decreased by 6.5% at the work site. The changes in PM₁₀ and PM_2.5 varied and did not exhibit a clear pattern. The air quality index (AQI) results indicated that the contribution to “undesired” air quality by O₃ was 35.29% of the lockdown period at the work site while contributions to undesired air quality by PM₁₀ and PM_2.5 were 75.6% and 100% at the work site, 94.5% and 100% at the residential site, and 96.7% and 100% at the traffic site, respectively. The findings of this study are useful for devising effective urban pollution abatement policies. Applying control measures comparable to the lockdown measures over one week will result in a decrease of approximately 19% and 15% in CO mean concentration and 25% and 18% in NO₂ mean concentration at residential and traffic sites, respectively. Full article

Background/Aim: In sub-Sahara Africa, few studies have investigated the short-term association between hospital admissions and ambient air pollution. Therefore, this study explored the association between multiple air pollutants and hospital admissions in Cape Town, South Africa. Methods: Generalized additive quasi-Poisson models were used within a distributed lag linear modelling framework to estimate the cumulative effects of PM₁₀, NO₂, and SO₂ up to a lag of 21 days. We further conducted multi-pollutant models and stratified our analysis by age group, sex, and season. Results: The overall relative risk (95% confidence interval (CI)) for PM₁₀, NO₂, and SO₂ at lag 0–1 for hospital admissions due to respiratory disease (RD) were 1.9% (0.5–3.2%), 2.3% (0.6–4%), and 1.1% (−0.2–2.4%), respectively. For cardiovascular disease (CVD), these values were 2.1% (0.6–3.5%), 1% (−0.8–2.8%), and −0.3% (−1.6–1.1%), respectively, per inter-quartile range increase of 12 µg/m³ for PM₁₀, 7.3 µg/m³ for NO₂, and 3.6 µg/m³ for SO₂. The overall cumulative risks for RD per IQR increase in PM₁₀ and NO₂ for children were 2% (0.2–3.9%) and 3.1% (0.7–5.6%), respectively. Conclusion: We found robust associations of daily respiratory disease hospital admissions with daily PM₁₀ and NO₂ concentrations. Associations were strongest among children and warm season for RD. Full article

With growing economic policy uncertainty (EPU) and the importance of protecting the natural environment worldwide, the relationship between EPU and carbon emissions should be investigated further. However, conclusions in the existing literature on the relationship between EPU and carbon emission are inconclusive. This paper aims to examine the influence of EPU on carbon emissions according to the Stochastic Impacts by Regression on Population, Affluence and Technology (STIRPAT) model. To investigate such essential issues, we conduct GMM estimations by utilizing cross-country data covering 137 countries during the period 1970–2018, obtained from World Bank and OECD statistics. Our empirical estimations support that EPU would bring about more carbon emissions, while we conduct empirical analysis by changing the system of measurement, employing alternative estimation and constructing new samples. Our study provides substantial policy implications for government participation in international treaties on environmental protection to mitigate environmental degradation. Full article

Malignant mesothelioma is a tumour of the serosal membranes, related to asbestos exposure. Median latency is in the order of 40 years in various registries, but small numbers of cases with shorter latencies have long been reported and often dismissed as unrelated to asbestos exposure. However, emerging data regarding the significance of inherited mutations leading to a predisposition to mesothelioma suggest that the causative effect of asbestos may be associated with shorter latencies in a subset of patients. Here, we describe a male patient with germline mutations in RAD51 and p53 who developed peritoneal mesothelioma 8.5 years after well-documented asbestos exposure and discuss the current literature on the subject. Mesothelioma in situ is now a WHO-accepted diagnosis, but preliminary data reveal a potential lead time of 5 or more years to invasive disease, and this is also a factor which may affect the recording of latency (and potentially survival) in the future. Full article

The aim of this work was to estimate the share of selected significant risk factors for respiratory cancer in the overall incidence of this disease and their comparison in two environmentally different burdened regions. A combination of a longitudinal cross-sectional population study with a US EPA health risk assessment methodology was used. The result of this procedure is the expression of lifelong carcinogenic risks and their contribution in the overall incidence of the disease. Compared to exposures to benzo[a]pyrene in the air and fibrogenic dust in the working air, several orders of magnitude higher share of the total incidence of respiratory cancer was found in radon exposures, for women 60% in the industrial area, respectively 100% in the non-industrial area, for men 24%, respectively 15%. The share of risks in workers exposed to fibrogenic dust was found to be 0.35% in the industrial area. For benzo[a]pyrene, the share of risks was below 1% and the share of other risk factors was in the monitored areas was up to 85%. The most significant share in the development of respiratory cancer in both monitored areas is represented by radon for women and other risk factors for men. Full article

The aim of the study was to determine the impact of air quality—analyzed on the basis of the model of integrating three types of air pollutants (ozone, O₃; particulate matter, PM; nitrogen dioxide, NO₂)—on the physical activity of soccer players. Study material consisted of 8927 individual match observations of 461 players competing in the German Bundesliga during the 2017/2018 and 2018/2019 domestic seasons. The measured indices included players’ physical activities: total distance (TD) and high-intensity effort (HIE). Statistical analysis showed that with increasing levels of air pollution, both TD (F = 13.900(3); p = 0.001) and HIE (F = 8.060(3); p = 0.001) decrease significantly. The worsening of just one parameter of air pollution results in a significant reduction in performance. This is important information as air pollution is currently a considerable problem for many countries. Improving air quality during training sessions and sports competitions will result in better well-being and sporting performance of athletes and will also help protect athletes from negative health effects caused by air pollution. Full article

Background: Short-term exposure to particulate matter (PM) has been related to mortality worldwide. Most evidence comes from studies conducted in major cities, while little is known on the effects of low concentrations of PM and in less urbanized areas. We aim to investigate the relationship between PM and all-cause mortality at national level in Italy. Methods: Daily numbers of all-cause mortality were collected for all 8092 municipalities of Italy, from 2006 to 2015. A satellite-based spatiotemporal model was developed to estimate daily PM₁₀ (inhalable particles) and PM_2.5 (fine particles) concentrations at 1-km resolution. Multivariate Poisson regression models were fit to estimate the association between daily PM and mortality at province level, and then, results were pooled with a random-effects meta-analysis. Associations were estimated by combination of age and sex and degree of urbanization of the municipalities. Flexible functions were estimated to explore the shape of the associations at low PM concentrations. Results: We analyzed 5,884,900 deaths (40% among subjects older than 85 years, 60% occurring outside the main urban areas). National daily mean (interquartile range) PM₁₀ and PM_2.5 concentrations were 23 (14) μg/m³ and 15 (11) μg/m³, respectively. Relative increases of mortality per 10 μg/m³ variation in lag 0–5 (average of last six days since death) PM₁₀ and PM_2.5 were 1.47% (95% Confidence Intervals (CI): 1.15%, 1.79%) and 1.96% (1.33%, 2.59%), respectively. Associations were highest among elderly and women for PM₁₀ only, similar between rural and urbanized areas, and were present even at low concentrations, e.g., below WHO guidelines. Conclusions: Air pollution was robustly associated with peaks in daily all-cause mortality in Italy, both in large cities and in less urbanized areas of Italy. Current WHO Air Quality Guidelines (2021) for PM₁₀ and PM_2.5 are not sufficient to protect public health. Full article

Few studies have examined rheumatoid arthritis (RA) risk and severity in Korean workers exposed to silica. We compared the hospitalization risk of RA between silica-exposed workers and the general Korean population. The study cohort consisted of male workers exposed to silica who had undergone at least one silica-associated special medical examination between 1 January 2000 and 31 December 2004 (N = 149,948). The data were from the Korea Occupation Safety and Health Agency. RA morbidity based on hospital admission records was estimated from 2000 to 2005 using the Korea National Health Insurance Service claims data. The standardized admission ratio (SAR) was calculated by dividing the observed number of admissions in silica-exposed workers by the expected number of admissions in the general reference population. For the sum of “Seropositive rheumatoid arthritis” (M05) and “Other rheumatoid arthritis” (M06), the SAR was higher in the silica-exposed group (1.34, 95% CI 1.08–1.64). For M05, workers with <10 years of silica exposure had a significantly higher SAR (2.54, 95% CI 1.10–5.01) than the general population. More silica-exposed workers without a diagnosis of pneumoconiosis were hospitalized for RA than the general population. Our analysis reaffirms the link between silica exposure and RA and suggests that the severity of RA is increased by silica. Further studies of silica-exposed workers with longer follow-up are needed. Full article

Ultrafine particles (UFPs) are particles smaller than 100 nanometers that are produced unintentionally during human activities or natural phenomena. They have a higher biological reactivity than bigger particles and can reach the placenta after maternal exposure. One study has shown an association between maternal occupational exposure to UFPs and fetal growth restriction. Yet few studies have focused on the effects of UFP exposure on placental histopathological lesions. The aim of this study was to investigate the association between maternal occupational exposure to UFPs and histopathological lesions of their placenta. The analyses were based on data from the ARTEMIS Center. A job-exposure matrix was used to assess occupational exposure to UFPs. The histopathological placental exam was performed by two pathologists who were blinded to the exposure of each subject. The examination was conducted in accordance with the recommendations of the Amsterdam consensus. The study sample included 130 placentas (30 exposed, 100 unexposed). Maternal occupational exposure to UFPs during pregnancy is significantly associated with placental hypoplasia (the phenomenon affected 61% of the exposed patients and 34% of the unexposed ones, p < 0.01). Further research is needed to explain its pathophysiological mechanisms. Full article

As part of the New Hampshire Birth Cohort Study, children 3 to 5 years of age participated in a personal PM_2.5 exposure study. This paper characterizes the personal PM_2.5 exposure and protocol compliance measured with a wearable sensor. The MicroPEM™ collected personal continuous and integrated measures of PM_2.5 exposure and compliance data on 272 children. PM_2.5, black carbon (BC), and brown carbon tobacco smoke (BrC-ETS) exposure was measured from the filters. We performed a multivariate analysis of woodstove presence and other factors that influenced PM_2.5, BC, and BrC exposures. We collected valid exposure data from 258 of the 272 participants (95%). Children wore the MicroPEM for an average of 46% of the 72-h period, and over 80% for a 2-day, 1-night period (with sleep hours counted as non-compliance for this study). Elevated PM_2.5 exposures occurred in the morning, evening, and overnight. Median PM_2.5, BC, and BrC-ETS concentrations were 8.1 μg/m³, 3.6 μg/m³, and 2.4 μg/m³. The combined BC and BrC-ETS mass comprised 72% of the PM_2.5. Woodstove presence, hours used per day, and the primary heating source were associated with the children’s PM_2.5 exposure and air filters were associated with reduced PM_2.5 concentrations. Our findings suggest that woodstove smoke contributed significantly to this cohort’s PM_2.5 exposure. The high sample validity and compliance rate demonstrated that the MicroPEM can be worn by young children in epidemiologic studies to measure their PM_2.5 exposure, inform interventions to reduce the exposures, and improve children’s health. Full article

Metabolic syndrome encompasses multiple conditions that increase the risk of cardiovascular disease, and exposure to environmental chemicals can cause metabolic syndrome. This cross-sectional study analyzed data from the US National Health and Nutrition Examination Survey (2003–2006) on 4318 adult participants to assess the association between acrylamide (AA) exposure and metabolic syndrome. Concentrations of hemoglobin-adducted AA (HbAA) and hemoglobin-adducted glycidamide (HbGA) were evaluated. Metabolic syndrome markers related to HbAA and HbGA and the effect of exposure to AA and GA on the prevalence of metabolic syndrome were studied by ANOVA and multivariate logistic regression analyses, respectively. HbAA concentration inversely correlated with the number of metabolic syndrome markers (p < 0.05). An increased HbAA concentration was noted with reduced high triglyceride and low high-density lipoprotein cholesterol levels in the adjusted model (p < 0.05). High fasting plasma glucose level significantly correlated with HbGA concentration in the adjusted model. In conclusion, AA exposure alters metabolic syndrome markers in adults. Additional clinical and animal studies will clarify the role of AA exposure at different stages in the progression of metabolic syndrome-related diseases. Full article

We appraise newly accumulated evidence of the impact of particle pollution on the brain, the portals of entry, the neural damage mechanisms, and ultimately the neurological and psychiatric outcomes statistically associated with exposures. PM pollution comes from natural and anthropogenic sources such as fossil fuel combustion, engineered nanoparticles (NP ≤ 100 nm), wildfires, and wood burning. We are all constantly exposed during normal daily activities to some level of particle pollution of various sizes—PM_2.5 (≤2.5 µm), ultrafine PM (UFP ≤ 100 nm), or NPs. Inhalation, ingestion, and dermal absorption are key portals of entry. Selected literature provides context for the US Environmental Protection Agency (US EPA) ambient air quality standards, the conclusions of an Independent Particulate Matter Review Panel, the importance of internal combustion emissions, and evidence suggesting UFPs/NPs cross biological barriers and reach the brain. NPs produce oxidative stress and neuroinflammation, neurovascular unit, mitochondrial, endoplasmic reticulum and DNA damage, protein aggregation and misfolding, and other effects. Exposure to ambient PM_2.5 concentrations at or below current US standards can increase the risk for TIAs, ischemic and hemorrhagic stroke, cognitive deficits, dementia, and Alzheimer’s and Parkinson’s diseases. Residing in a highly polluted megacity is associated with Alzheimer neuropathology hallmarks in 99.5% of residents between 11 months and ≤40 y. PD risk and aggravation are linked to air pollution and exposure to diesel exhaust increases ALS risk. Overall, the literature supports that particle pollution contributes to targeted neurological and psychiatric outcomes and highlights the complexity of the pathophysiologic mechanisms and the marked differences in pollution profiles inducing neural damage. Factors such as emission source intensity, genetics, nutrition, comorbidities, and others also play a role. PM_2.5 is a threat for neurological and psychiatric diseases. Thus, future research should address specifically the potential role of UFPs/NPs in inducing neural damage. Full article

(1) Background: Years of life lost (YLL) as a surrogate of health is important for supporting ambient air pollution related policy decisions. However, there has been little comprehensive evaluation of the short-term impact of air pollution on cause-specific YLL, especially in China. Hence in this study, we selected China as sentinel region in order to conduct a meta-analysis to evaluate disease-specific YLL due to all the main ambient air pollutants. (2) Methods: A meta-analysis was conducted to evaluate disease-specific YLL due to the main ambient air pollutants in China, and 19 studies were included. We conducted methodological quality and risk of bias assessment for each included study as well as for heterogeneity and publication bias. Subgroup analysis and sensitivity analysis were also performed. (3) Results: Meta-analysis indicated that increases in PM_2.5, PM₁₀, SO₂ and NO₂ were associated with 1.99–5.84 years increase in YLL from non-accidental diseases. The increase in YLL to cardiovascular disease (CVD) was associated with PM₁₀ and NO₂, and the increase in YLL to respiratory diseases (RD) was associated with PM₁₀. (4) Conclusions: Ambient air pollution was observed to be associated with several cause-specific YLL, increasing especially for elderly people and females. Full article

The novel coronavirus pandemic has resulted in an urgent need to study the risk of infection from aerosols generated during dental care and to conduct a review of infection controls. However, existing studies on aerosol particles related to dental treatment have mainly evaluated only the scattering range. Few studies have been conducted on the specifics of the generation of aerosol particles in clinical settings, their mechanisms and patterns of distribution throughout open or enclosed spaces, the duration that they remain suspended in air, and the amount and size of particles present. To minimize the influence of background particles, laser lights, a high-sensitivity camera, and particle counters were used in a large super clean laboratory to investigate the dynamics of aerosols generated during the operation of dental micromotors. The results indicate that aerosols tend to scatter upward immediately after generation and then gradually disperse into the surroundings. Most of the particles are less than 5 µm in size (only a few are larger), and all particles are widely distributed over the long term. Our research clearly elucidates that aerosols produced in dental care are distributed over a wide area and remain suspended for a considerable time in dental clinics before settling. Full article

Background: Particulate matter and urban air pollution affect the human body and can lead to death. Epidemiological studies should consider exposure to pollutants and the diverse responses of individuals, depending on their sensitivity to the pollutants. Methods: In this study, air pollution measurements were obtained hourly at measuring stations operated by national and local governments to increase the reliability of the measured values. A β-ray absorption method was used to analyze the measurements of fine dust and determine the particulate matter content. Results: The air pollution data were log-linear, thereby enabling a comparison of data from different time periods. The comparison was made by focusing on the period of the implementation of Seoul’s fine dust policy. It was observed that the cancer incidence rate decreased after the implementation of the policy. The data on individual characteristics were obtained from a survey of Seoul citizens conducted from 2015 to 2016 using indicators such as quality of life and the social trust of Seoul citizens. Conclusion: The survey on the living environment and residence indicated that 80% of the heads of households were men. Women had a greater dissatisfaction than men with their residential, economic, and social environments. The survey questions on well-being were related to elements of internal and external environments, such as air pollution, noise, and fine dust. Full article

Dissecting a human cadaver is an irreplaceable practice in general training of medical students. Cadavers in anatomy laboratories are usually preserved in formalin, an embalming fluid whose basic component is formaldehyde (FA). The aim of this study is to assess the cancer risk of employees and students that are exposed to FA based on the results of three monitoring campaigns, as well as to suggest permanent solutions to the problem of FA exposure based on the results obtained. Three sampling campaigns of formaldehyde concentration in indoor environments were conducted at five different locations at the Anatomy Department of the Faculty of Medicine with the purpose of assessing permanent employees’ and medical faculty first year students’ exposure to FA. Indoor air was continuously sampled during 8 h of laboratory work and analyzed in accordance with the NIOSH Method 3500. Exceeding of the 8 h time-weighted average (8 h TWA) values recommended by Occupational Safety and Health Administration (OSHA) of 0.75 ppm was recorded in 37% of the samples during the three-month monitoring campaign. Cancer risk assessment levels for permanent employees were in the range from 6.43 × 10⁻³ to 8.77 × 10⁻⁴, while the cancer risk assessment levels for students ranged from 8.94 × 10⁻⁷ to 1.83 × 10⁻⁶. The results of the research show that cancer risk assessment for employees is several thousand times higher than the limit recommended by the EPA (10⁻⁶) and point to the importance of reducing exposure to formaldehyde through the reconstruction of the existing ventilation system, continual monitoring, the use of formaldehyde-free products, and plastination of anatomical specimens. Full article

Background: We conducted a meta-analysis to quantitatively assess the association between asbestos exposure and esophageal cancer. Methods: We systematically collected articles from three electronic databases and calculated the pooled standardized mortality rate (SMR) from the meta-analysis. Subgroup analysis according to the type of asbestos exposure, follow-up years, sample size, industry classification, sex, and high-dose exposure was conducted. Results: From 242 studies, 34 cohort studies were included in our meta-analysis. Pooled SMR was positively associated with asbestos exposure and esophageal cancer (pooled SMR = 1.28; 95% confidence interval (CI) 1.19–1.38, p < 0.00001). In the subgroup analysis, (1) chrysolite, (2) four groups with follow-up over ten years, (3) the textile industry and shipyard, (4) both male and female, and (5) eight studies on highest asbestos exposure, all the subgroups showed significantly increased pooled SMRs. Conclusion: Asbestos exposure was significantly and positively associated with esophageal cancer, especially chrysolite. Considering the long latency period, we suggest that patients should be followed up for cancer, including esophageal cancer, for over ten years. Full article

The impact of the lockdown, during the period from March to June in 2020, upon the air quality of the Basque Country in northern Spain is analyzed. The evaluation accounts for the meteorology of the period. Daily and sub-daily analysis of aerosol and ozone records show that the territory was repeatedly affected by episodes of pollutants from outer regions. Three episodes of PM₁₀ and ten of PM_2.5 were caused by transported anthropogenic European sulfates, African dust, and wildland fires. The region, with a varied orographic climatology, shows high and diverse industrial activity. Urban and interurban road traffic of the region decreased by 49% and 53%, respectively, whereas industrial activity showed a lower reduction of 20%. Consequently, the average concentrations of NO₂ in the cities during the period fell to 12.4 µg·m⁻³ (−45%). Ozone showed up to five exceedances of the WHOAQG for the daily maximum 8-h average in both rural and urban sites, associated with transport through France and the Bay of Biscay, under periods of European blocking anticyclones. However, averages showed a moderate decrease (−11%) in rural environments, in line with the precursor reductions, and disparate changes in the cities, which reproduced the weekend effect of their historical records. The PM₁₀ decreased less than expected (−10% and −21%, in the urban and rural environments, respectively), probably caused by the modest decrease of industrial activity around urban sites and favorable meteorology for secondary aerosol formation, which could also influence the lower changes observed in the PM_2.5 (−1% and +3% at the urban and rural sites, respectively). Consequently, in a future low NOx traffic emission scenario, the inter-regional PM and ozone control will require actions across various sectors, including the industry and common pollution control strategies. Full article

Zimbabwe has two major factories that have been manufacturing chrysotile asbestos cement products since the 1940s. Exposure monitoring of airborne fibres has been ongoing since the early 1990s. This study examines trends in personal exposure chrysotile asbestos fibre concentrations for the period 1996–2016. Close to 3000 historical personal exposure measurements extracted from paper records in the two factories were analysed for trends in exposure. Exposure over time was characterised according to three time periods and calendar years. Mean personal exposure chrysotile asbestos fibre concentrations generally showed a downward trend over the years in both factories. Exposure data showed that over the observed period 57% and 50% of mean personal exposure chrysotile asbestos fibre concentrations in the Harare and Bulawayo factories, respectively, were above the OEL, with overexposure being exhibited before 2008. Overall, personal exposure asbestos fibre concentrations in the factories dropped from 0.15 f/mL in 1996 to 0.05–0.06 f/mL in 2016—a decrease of 60–67%. These results can be used in future epidemiological studies, and in predicting the occurrence of asbestos-related diseases in Zimbabwe. Full article

The results of air quality monitoring show significantly increased concentrations of polycyclic aromatic hydrocarbons (PAH) and arsenic in the area located near the town of Kladno in Central Bohemia, Czech Republic. The region of interest is historically associated with coal mines and steelworks. Source apportionment using the method of Positive Matrix Factorization (PMF) at three sites has been used to try to explain the reasons of the increased PM_2.5, benzo[a]pyrene, and arsenic concentrations in the ambient air. Based on the PMF analysis, nine factors explaining the atmospheric aerosol mass have been identified. The PMF results showed that most of the aerosol mass originated from residential heating (about one third of PM_2.5), both primary particles and secondary organic aerosols induced by road traffic (up to approximately 25%), soil and other mineral dust (about 15%), secondary inorganic aerosol ammonium sulfate (up to 16%), ammonium nitrate (up to 14%) and other sulfates (up to 9%). The main source of arsenic and benzo[a]pyrene was residential heating, which accounted for two-thirds and 80% of their total mass, respectively. The results have pointed to the most important measures for effective air quality protection in the area of interest: replacing coal fuel and old boilers used for residential heating in order to reduce arsenic and PAH emissions and mitigate sources of secondary particles precursors to decrease PM concentrations. Full article

Pneumonia, one of the important causes of death in children, may be induced or aggravated by particulate matter (PM). Limited research has examined the association between PM and its constituents and pediatric pneumonia-related emergency department (ED) visits. Measurements of PM_2.5, PM₁₀, and four PM_2.5 constituents, including elemental carbon (EC), organic carbon (OC), nitrate, and sulfate, were extracted from 2007 to 2010 from one core station and two satellite stations in Kaohsiung City, Taiwan. Furthermore, the medical records of patients under 17 years old who had visited the ED in a medical center and had a diagnosis of pneumonia were collected. We used a time-stratified, case-crossover study design to estimate the effect of PM. The single-pollutant model demonstrated interquartile range increase in PM_2.5, PM₁₀, nitrate, OC, and EC on lag 3, which increased the risk of pediatric pneumonia by 18.2% (95% confidence interval (Cl), 8.8–28.4%), 13.1% (95% CI, 5.1–21.7%), 29.7% (95% CI, 16.4–44.5%), 16.8% (95% CI, 4.6–30.4%), and 14.4% (95% Cl, 6.5–22.9%), respectively. After PM_2.5, PM₁₀, and OC were adjusted for, nitrate and EC remained significant in two-pollutant models. Subgroup analyses revealed that nitrate had a greater effect on children during the warm season (April to September, interaction p = 0.035). In conclusion, pediatric pneumonia ED visit was related to PM_2.5 and its constituents. Moreover, PM_2.5 constituents, nitrate and EC, were more closely associated with ED visits for pediatric pneumonia, and children seemed to be more susceptible to nitrate during the warm season. Full article

Background: No study has compared the respiratory effects of environmental and occupational particulate exposure in healthy adults. Methods: We estimated, by a systematic review and meta-analysis, the associations between short term exposures to fine particles (PM_2.5 and PM₄) and certain parameters of lung function (FEV₁ and FVC) in healthy adults. Results: In total, 33 and 14 studies were included in the qualitative synthesis and meta-analyses, respectively. In environmental studies, a 10 µg/m³ increase in PM_2.5 was associated with an FEV₁ reduction of 7.63 mL (95% CI: −10.62 to −4.63 mL). In occupational studies, an increase of 10 µg/m³ in PM₄ was associated with an FEV₁ reduction of 0.87 mL (95% CI: −1.36 to −0.37 mL). Similar results were observed with FVC. Conclusions: Both occupational and environmental short-term exposures to fine particles are associated with reductions in FEV₁ and FVC in healthy adults. Full article

Construction is an important segment of the economy that employs millions of people. Construction dust is an occupational health hazard to millions of construction workers worldwide. The hazards associated with respirable dust depend upon its particulate size distribution and chemical composition, as these determine the deposition pattern in the respiratory tract and reactivity, respectively. This study presents characterization of the size and composition of the dust from two key construction materials—cast cement and poured concrete. The dust was generated by cutting the cured cement and concrete blocks using an 18” hand-held circular saw as used in highway and building construction. Transmission electron microscopy, scanning electron microscopy, dynamic light scattering, and laser diffraction were performed for the size analysis of the particles. Energy dispersive spectroscopy and X-ray photoelectron spectroscopy were used for chemical analysis. X-ray diffraction was used for phase identification. Electron diffraction patterns were obtained to assess the crystallinity of individual particles. They confirm the crystallinity of particles of different size and shapes. With a particle size range between 0.5 μm and 10 μm, greater than 90% of particles fell below 2.5 μm, presenting a respirable health concern. Crystalline compounds including the metals Al, Ca, Fe, Mg, Na, and K were detected. The concrete particles were most enriched in crystalline silica with a concentration of more than 30% by weight. The presence of metals and high crystalline silica content pose a serious health concern to construction workers. Full article

In order to determine the pollution sources and human health risks of metal elements in PM_2.5, samples were collected by a large flow particulate matter sampler in the four seasons in 2013, 2015, and 2017 (January, April, July, and October). The mass concentrations of 10 metals (Ti, V, Cr, Mn, Ni, Cu, Zn, As, Cd, and Pb) were analyzed. The sources of heavy metals were identified by Unmix, and the potential non-carcinogenic/carcinogenic risk was evaluated. The influences of local and regional sources were also explored during the high-carcinogenic risk period (HCRP). The wind field and 72 h backward trajectories were performed to identify the potential local and regional sources in HCRP. The results showed that the average annual concentrations of PM_2.5 in the urban area of Handan city were 105.14, 91.18, and 65.85 μg/m³ in 2013, 2015, and 2017, respectively. The average daily concentrations of the metals in PM_2.5 in January were higher than that of April, July, and October. The average mass concentrations of the 10 heavy metal elements in PM_2.5 were 698.26, 486.92, and 456.94 ng·m⁻³ in 2013, 2015, and 2017, respectively. The main sources of the metals in PM_2.5 were soil dust sources, vehicular emissions, coal burning, and industrial activities. The carcinogenic risks of Cr and As were above 1 × 10⁻⁶ over the three years. Wind direction analysis showed that the potential local sources were heavy industry enterprises and the economic development zone. The backward trajectory analysis indicated that PM_2.5 long transported from Shandong, Henan, and the surrounding cities of Handan had quite an impact on the heavy metals contained in the atmosphere of the studied area. The health risk assessment results demonstrated that the trend for non-carcinogenic risk declined, and there was no non-carcinogenic risk in 2017. However, the carcinogenic risk levels were high over the three years, particularly in January. Full article

Nitrogen dioxide (NO₂) has a great influence on atmospheric chemistry. Scientifically identifying the temporal-spatial characteristics of NO₂ distribution and their driving factors will be of realistic significance to atmospheric governance in the Yangtze River Economic Belt (YREB). Based on the NO₂ data derived from the TROPOspheric Monitoring Instrument (TROPOMI) onboard the Sentinel-5 satellite (2017~present), spatial autocorrelation analysis, standard deviation ellipse (SDE), and geodetectors were used to systematically analyze the spatial-temporal evolution and driving factors of tropospheric NO₂ vertical column density (NO₂ VCD) in the YREB from 2019 to 2020. The results showed that the NO₂ VCD in the YREB was high in winter and autumn and low in spring and summer (temporal distribution), and high in the northeast and low in the southwest (spatial distribution), with significant spatial agglomeration. High-value agglomeration zones were collectively and stably distributed in the east region, while low-value zones were relatively dispersed. The explanatory power of each potential factor for the NO₂ VCD showed regional and seasonal variations. Surface pressure was found to be a core influencing factor. Synergistic effects of factors presented bivariate enhancement or nonlinear enhancement, and interaction between any two factors strengthened the explanatory power of a single factor for the NO₂ VCD. Full article

In this paper, an analysis of the possibility of passive determination of the degree of environmental pollution based on data from the leaf blade of mulberry is made. With existing solutions in this area, the mulberry has been found to be under-researched. A disadvantage of the available solutions is that spectral indices are used, which is not a sufficient criterion for passively determining the degree of air pollution based on the surface characteristics of the mulberry leaves. Methods have been used to reduce the amount of data by latent variables and principal components. It has been found that a kernel variant of the principal components, combined with linear discriminant analysis, is an appropriate method for distinguishing the degree of air pollution from mulberry leaf data. The results obtained can be used to refine the approaches used to passively determine the degree of air pollution in the habitat area of the plant. Methods and software tools could be used to develop mobile applications and new approaches to remote sensing, in express determination of the degree of environmental pollution, according to data from the mulberry leaves. Full article