Effects Of Fine Particulate Matter Research Articles

Impact of acute PM2.5 exposure on pediatric blood lead levels: evidence from Beijing, China

Research on the effects of fine particulate matter (PM2.5) on blood lead levels (BLL), particularly in children, remains limited. This study aimed to investigate the relationship between acute ambient PM2.5 exposure and BLL in children aged below 14. A total of 23,732 children were included in the study, with BLL measured using atomic absorption spectrometry. Generalized additive models (GAM) were employed to analyze the connection between children’s BLL and acute PM2.5 exposure. From April 2008 to June 2017, Beijing’s average PM2.5 concentration was 91.71 ± 74.55 μg/m³, approximately 2.62 times higher than the annual average concentration recommended by the WHO Ambient Air Quality Standard (35 μg/m³). The mean (±SD) BLL of children was 0.2105 ± 0.0963 μmol/L, with a median of 0.20 μmol/L. The data indicated an increase in BLL with age and a significant difference in BLL between boys and girls (p < 0.05). The analysis revealed a non-linear relationship between BLL and PM2.5 exposure after adjusting for variables such as gender, age, blood levels of Cu, Fe, Ca, Mg, Zn, analysis batch, and heating season. PM2.5 exposure significantly impacted children’s BLL.

Effects of fine particulate matter bound heavy metals on intentional self-harm deaths in Guangzhou, China, insight from core chemical constituents.

Fine particulate matter (PM2.5) is one of the major threats to human health, and may partly responsible for intentional self-harm deaths, while the limited results seemed contradictory. Further analysis on PM2.5 constituents may provide more reliable evidence. Heavy metals are crucial toxic components of PM2.5 that may induce suicide behavior. What role do PM2.5-bound heavy metals play in a threat to intentional self-harm death is still unclear. Two-year data of daily PM2.5-bound heavy metals (including metalloids) and daily intentional self-harm deaths were collected in Guangzhou. Bayesian kernel machine regression, weighted quantile sum, and quantile-based g-computation models were employed to depict the relationships between heavy metals and intentional self-harm deaths. The number of intentional self-harm deaths was 217 and 283 for 2015 and 2016, respectively. A positive correlation was found between the combined effect of the 13 heavy metals and intentional self-harm deaths. Nickel, cadmium, and iron were the primary contributors to this positive correlation. Heavy metal components play significant roles in PM2.5-related intentional self-harm deaths, and targeted source control measures are warranted to protect residents from suicide.

Effects of fine particulate matter from wildfire and non-wildfire sources on emergency-department visits in people who were housed and unhoused in San Diego County (CA, USA) during 2012–20: a time-stratified case–crossover study

Being unhoused can increase vulnerability to adverse health effects due to air pollution. We aimed to quantify changes in emergency-department visits during and after exposure to wildfire-specific and non-wildfire particulate matter 2·5 μm or less in diameter (PM2·5) in San Diego County (CA, USA) in people who were both unhoused and housed. For this time-stratified case-crossover study, we used data on exposure to wildfire-specific PM2·5 in California and individual-level data for people admitted to the emergency departments of two hospitals (UC San Diego Health emergency departments at La Jolla and Hillcrest, San Diego) in San Diego County between July 1, 2012, and Dec 31, 2020. People with a postcode outside of San Diego County were excluded. Demographic information was age group, race or ethnicity, and transport to the emergency department. Wildfire-specific PM2·5 concentration at the postcode level was previously estimated using an ensemble model that combined multiple machine-learning algorithms and explanatory variables obtained via data on 24-h mean PM2·5 concentrations from the US Environmental Protection Agency Air Quality System. Conditional logistic regression models were applied, adjusting for specific humidity, wind velocity, and maximum temperature extracted from the US Gridded Surface Meteorological Dataset. Housing status was established by registration staff or triage nurses on arrival at the emergency department. For people who were unhoused, exposure was defined based on the weighted mean PM2·5 concentration at the city level proportional to the number of people who were unhoused in each specific city across urban centres in San Diego County. For people who were housed, we used residence postcode to measure exposure. We assessed the association between PM2·5 from wildfire and non-wildfire sources and emergency-department visits in people who were housed and unhoused. There were 587 562 emergency-department visits at the two hospitals, 76 407 (13·0%) of which were by people who were unhoused. People who were housed had a higher exposure to overall PM2·5 (24-h mean over the study period of 9·904 mg/m3, SD 3·445) and non-wildfire PM2·5 (9·663, 2·977) than people who were unhoused (9·863, 3·221; 9·557, 2·599). However, people who were unhoused had a higher exposure to wildfire-specific PM2·5 (0·305, 1·797) than people who were housed (0·240, 1·690). Overall PM2·5 exposure was associated with increased odds of emergency-department visits for both people who were housed (odds ratio 1·003, 95% CI 1·001-1·004 per 1 μg/m3 PM2·5 for 0-3 days after exposure) and people who were unhoused (1·004, 1·000-1·008 for 0-3 days after exposure). We found that non-wildfire PM2·5 was associated with emergency-department visits among people who were housed (1·003, 1·002-1·005 for 0-3 days after exposure) and wildfire-specific PM2·5 was associated with emergency-department visits in people who were unhoused (1·006, 1·001-1·011 for 0-3 days after exposure). People who were unhoused in San Diego County were more likely to visit emergency departments after exposure to increased wildfire-specific PM2·5. As the intensity and frequency of wildfires increase, understanding risk factors for vulnerable populations, such as people who are unhoused, is crucial to develop effective adaptation strategies. US National Institutes of Health, National Institute on Aging.

The role of leukocytes in cognitive impairment due to long-term exposure to fine particulate matter: A large population-based mediation analysis.

Our understanding of how fine particulate matter (PM2.5) impacts cognitive functioning is limited. Systemic inflammation processes may play a role in mediating this effect. This prospective cohort study used data from 66,254 participants aged 18+ between 2006 and 2015 from the Dutch Lifelines Cohort Study and Biobank. Causal mediation analysis was conducted to examine the impact of ambient PM2.5 exposure on cognitive processing time (CPT), using the change in white blood cell (WBC) count and its subtypes as potential mediators. Heightened PM2.5 exposure was associated with slower CPT (total effect=81.76×10-3, 95% confidence interval [CI] 59.51×10-3-105.31×10-3). The effect was partially mediated via increased WBC count (indirect effect [IE]=0.42×10-3, 95% CI 0.07×10-3-0.90×10-3), particularly driven by an increase in monocytes (IE=0.73×10-3, 95% CI 0.24×10-3-1.31×10-3). Systemic inflammation processes may partially explain the harmful effects of PM2.5 on cognitive functioning, why lower levels of systemic inflammation may help contain its neurotoxic effects. The pathways leading to the neurotoxic effects of fine particulate matter (PM2.5) are poorly understood. We analyzed data from over 66,000 participants using causal pathway analysis. Increased white blood cell (WBC) count mediates the effect of PM2.5 on cognitive functioning. Monocyte count played a crucial role in this low-pollution setting. Systemic inflammation may contribute to the neurotoxic effects of PM2.5.

Association between ambient air pollution and respiratory health in Kampala, Uganda: Implications for policy and practice

Ambient air pollution and weather have an impact on respiratory diseases. This study analysed effects of fine particulate matter (PM2.5) on monthly respiratory-related healthcare facility visits and admissions (herein referred to as events) in Kampala, whilst considering meteorological factors.Monthly healthcare facility events for neonatal pneumonia, asthma, pneumonia and COPD between 2019 and 2020 were retrospectively extracted from the District Health Information Software 2. PM2.5 and meteorological data were obtained from 45 monitoring stations and 5 weather stations in Kampala. Associations between air pollution and healthcare facility events were examined using generalised additive models (GAM) adjusted for rainfall, temperature and humidity.Multivariate analysis showed positive association between monthly PM2.5 with healthcare facility visits due to asthma (incident rate ratio-IRR = 1.007, 95 % CI: 1.002–1.013; p < 0.05) and admissions due to pneumonia (IRR = 1.007, 95 % CI: 1.001–1.013; p < 05). Healthcare facility events were associated with PM2.5 (IRR = 1.005; 95 % CI: 1.002–1.009; p < 0.05) and relative humidity (EDF = 1.000; p < 0.05).PM2.5 impacted on healthcare facility events in Kampala and association was influenced by meteorological factors. However, lack of data for daily healthcare facility events could have affected accuracy of the impact therefore further analyses are needed. Our characterisation could support facilities in development of early warning tools for air pollution events.

Fine particulate matter potentiates Th17-cell pathogenicity in experimental autoimmune uveitis via ferroptosis

The effect of fine particulate matter (PM2.5) on the development of uveitis remains unclear. Therefore, this study was designed to investigate the role of PM2.5 in experimental autoimmune uveitis (EAU) and its potential mechanism. Our results showed that PM2.5 could exacerbate the activity of EAU, as evidenced by severer clinical and pathological changes, correlated with elevated Th17 cells frequency and IL-17A expression. Proteomic analysis revealed ferroptosis was the most significant pathway. In vivo, the levels of Fe2+, ROS, lipid ROS, and malondialdehyde, as well as the expression of TFRC, HMOX1, FTH1, and FTL1 in CD4+ T cells were increased, while GSH/GSSG ratio and the expression of ACSL1 and GPX4 were decreased after PM2.5 exposure. In vitro, the expression of TFRC and HMOX1 were increased, while the expression FTH1, FTL1, ACSL1, and GPX4 were decreased after PM2.5 exposure. Ferrostatin-1 effectively alleviated PM2.5-induced intraocular inflammation and suppressed the frequency of Th17 cells. These results suggest that PM2.5 could aggravate intraocular inflammation and immune response in EAU mice through ferroptosis. Ferroptosis could be a potential marker for the prevention and treatment of uveitis.

Shedding light on the cellular mechanisms involved in the combined adverse effects of fine particulate matter and SARS-CoV-2 on human lung cells

Airborne pathogens represent a topic of scientific relevance, especially considering the recent COVID-19 pandemic. Air pollution, and particulate matter (PM) in particular, has been proposed as a possible risk factor for the onset and spread of pathogen-driven respiratory diseases. Regarding SARS-CoV-2 infection, exposure to fine PM (PM2.5, particles with an aerodynamic diameter < 2.5 μm) has been associated with increased incidence of the COVID-19 disease.To provide useful insights into the mechanisms through which PM might be involved in infection, we exposed human lung cells (A549) to PM2.5 and SARS-CoV-2, to evaluate the toxicological properties and the molecular pathways activated when airborne particles are combined with viral particles. Winter PM2.5 was collected in a metropolitan urban area and its physico-chemical composition was analyzed. A549 cells were exposed to SARS-CoV-2 concomitantly or after pre-treatment with PM2.5. Inflammation, oxidative stress and xenobiotic metabolism were the main pathways investigated. Results showed that after 72 h of exposure PM2.5 significantly increased the expression of the angiotensin-converting enzyme 2 (ACE2) receptor, which is one of the keys used by the virus to infect host cells. We also analyzed the endosomal route in the process of internalization, by studying the expression of RAB5 and RAB7. The results show that in cells pre-activated with PM and then exposed to SARS-CoV-2, RAB5 expression is significantly increased. The activation of the inflammatory process was then studied. Our findings show an increase of pro-inflammatory markers (NF-kB and IL-8) in cells pre-activated with PM for 72 h and subsequently exposed to the virus for a further 24 h, further demonstrating that the interaction between PM and SARS-CoV-2 determines the severity of the inflammatory responses in lung epithelial cells. In conclusion, the study provides mechanistic biological evidence of PM contribution to the onset and progression of viral respiratory diseases in exposed populations.

Gut microbiota partially mediates the effects of fine particulate matter on blood lipids metabolism

Gut microbiota partially mediates the effects of fine particulate matter on blood lipids metabolism

Short-term effects of fine particulate matter from biomass combustion and Saharan dust intrusions on emergency hospital admissions due to mental and behavioural disorders, anxiety and depression in Spain

Climate change is affecting both the frequency and scale of wildfires, as well as the increase in the number of days with Saharan dust intrusions. Traditionally, studies have focused on the extent to which the increase in fine particulate matter (PM) has had an impact on cardio-respiratory diseases, but (apart from PM) not on how the meteorological and pollution conditions in these situations affect other diseases, such as those linked to mental health.This study therefore sought to ascertain how daily mean PM10, PM 2.5, NO2, O3 concentrations and daily maximum temperature in heat waves influence daily emergency hospital admissions in Spain caused by mental and behavioural disorders, depression and anxiety on days with PM from biomass combustion and/or Saharan dust intrusions, as compared to days without such conditions, across the period 2009–2018.Our results indicate that on days on which there is biomass combustion, PM concentrations have a statistically significant effect on emergency admissions due to mental disorders, probably related with the toxicity of these particles. Yet on days with intrusions of Saharan dust rather than PM, it is the other variables considered in the analysis that are most closely linked to these types of admissions. The results of this study thus point to the need to implement public health prevention plans which take into account the joint effect of various environmental risk factors that act synergistically in given situations.

Prediction of developmental toxic effects of fine particulate matter (PM2.5) water-soluble components via machine learning through observation of PM2.5 from diverse urban areas

The global health implications of fine particulate matter (PM2.5) underscore the imperative need for research into its toxicity and chemical composition. In this study, zebrafish embryos exposed to the water-soluble components of PM2.5 from two cities (Harbin and Hangzhou) with differences in air quality, underwent microscopic examination to identify primary target organs. The Harbin PM2.5 induced dose-dependent organ malformation in zebrafish, indicating a higher level of toxicity than that of the Hangzhou sample. Harbin PM2.5 led to severe deformities such as pericardial edema and a high mortality rate, while the Hangzhou sample exhibited hepatotoxicity, causing delayed yolk sac absorption. The experimental determination of PM2.5 constituents was followed by the application of four algorithms for predictive toxicological assessment. The random forest algorithm correctly predicted each of the effect classes and showed the best performance, suggesting that zebrafish malformation rates were strongly correlated with water-soluble components of PM2.5. Feature selection identified the water-soluble ions F− and Cl− and metallic elements Al, K, Mn, and Be as potential key components affecting zebrafish development. This study provides new insights into the developmental toxicity of PM2.5 and offers a new approach for predicting and exploring the health effects of PM2.5.

The effects of fine particulate matter (SRM 2786) on three different 3D lung models exposed at the air-liquid interface – A comparative study

3D cell culture models exposed at the air-liquid interface (ALI) represent a potential alternative to animal experiments for hazard and risk assessment of inhaled compounds. This study compares cocultures composed of either Calu-3, A549 or HBEC3-KT lung epithelial cells, cultured together with THP-1-derived macrophages and EA.hy926 endothelial cells, in terms of barrier capacity and responses to a standard reference sample of fine particulate matter (SRM 2786). High-content imaging analysis revealed a similar cellular composition between the different cell models. The 3D cell cultures with Calu-3 cells showed the greatest barrier capacity, as measured by transepithelial electrical resistance and permeability to Na-fluorescein. Mucus production was detected in 3D cell cultures based on Calu-3 and A549 cells. Exposure to SRM 2786 at ALI increased cytokine release and expression of genes associated with inflammation and xenobiotic metabolism. Moreover, the presence of THP-1-derived macrophages was central to the cytokine responses in all cell models. While the different 3D cell culture models produced qualitatively similar responses, more pronounced pro-inflammatory responses were observed in the basolateral compartment of the A549 and HBEC3-KT models compared to the Calu-3 model, likely due to their reduced barrier capacity and lower retention of secreted mediators in the apical compartment.

The effect of fine particulate matter (PM2.5) pollution on health inequality: an intergenerational perspective.

Air pollution poses a serious challenge to public health and simultaneously exacerbating regional & intergenerational health inequality. This research introduces PM2.5 pollution into the intergenerational health transmission model, and estimates its impact on health inequality in China using Ordered Logit Regression (OLR) and Multi-scale Geographically Weighted Regression (MGWR) model. The results indicate that PM2.5 pollution exacerbate the intergenerational health inequality, and its impacts show inconsistency across family income levels, parental health insurance status, and area of residence. Specifically, it is more difficult for offspring in low-income families to escape from the influence of unhealthy family to become upwardly mobile. Additionally, this health inequality is more significant in households in which at least one parent does not have health insurance. Moreover, the intergenerational solidification caused by PM2.5 pollution is higher in the east and lower in the west. Both the PM2.5 level and solidification effect are high in Beijing-Tianjin-Hebei region, Yangtze River Delta region and central areas of China, which is the focus of air pollution management. These findings suggest that more emphasis should be placed on family-based health promotion. In areas with high PM2.5 pollution levels, resources, subsidies and air pollution protection should be provided for less healthy families with lower incomes and no health insurance.

A panel study of exposure to fine particulate matter and modeled respiratory deposition on biomarkers of inflammation, blood coagulation, and oxidative stress in healthy young adults in Hefei, China

Evidence is scarce on the acute cardiovascular health effects of fine particulate matter (PM2.5) and its respiratory tract depositions. We performed a panel study in Hefei, China to explore the relations of PM2.5 and its depositions in 3 respiratory tract regions over different lag times with a range of cardiovascular biomarkers among 40 college students and the potential mediating effects of inflammation. We found significant effects of PM2.5 exposure on the alterations of biomarkers at specific lag days, in a concentration-response manner, even at PM2.5 level below Chinese Ambient Air Quality Standard (CAAQS) Grade I (35 μg/m3). For example, per 10 μg/m3 increase in PM2.5 concentration was associated with −9.33% increase in ADAMTS13 on lag 0-1d. The corresponding increases in D-Dimer, GM-CSF, and MCP-1 for the same change in PM2.5 concentration on lag 5-6d were 30.51%, 11.43%, and 20.05%. Besides, tracheobronchial region (TB) deposition presented more evident effects on these biomarkers than that in PM2.5. Additionally, we observed greater associations of PM2.5-biomarkers among females, those with abnormal body mass index (BMI), and those with physical activity. The results indicated that short-term PM2.5 exposure and its respiratory tract depositions were concentration-responsive associated with damaged cardiovascular health via inducing blood coagulation, oxidative stress and inflammation among healthy young adults even at concentration below CAAQS Grade I. Elevated serum levels of systemic inflammation may be partly responsible for the effects of PM2.5 and its respiratory tract depositions on coagulation function.

Exploring the adverse effect of fine particulate matter (PM2.5) on wildland firefighters’ pulmonary function and DNA damage

Chiang Mai encounters severe pollution during the wildfire season. Wildland firefighters encounter various hazards while engaged in fire suppression operations, which encompass significant exposure to elevated concentrations of air pollutants resulting from combustion, especially particulate matter. The adverse effects of wildfire smoke on respiratory health are a significant concern. The objective of this study was to examine the potential adverse effects of PM2.5 exposure on the respiratory function and DNA damage of wildland firefighters. This prospective cohort study conducted in Chiang Mai from January to May 2022 planned to evaluate the health status of wildland firefighters during the pre-peak, peak, and post-peak ambient air pollution seasons. The measurement of PM2.5 was done at every forest fire station, as well as utilizing data from the Pollution Control Department. Participants received general health examinations, spirometry evaluations, and blood tests for DNA damage analysis. Pair t-tests and multiple regression models were used to examine the connection between pulmonary function parameters (FVC, FEV1) and PM2.5 concentration, with a significance level of P < 0.05. Thirty-three peak-season and twenty-one post-peak-season participants were enrolled. Four pre-peak-season wildland firefighters had FVC and FEV1 declines of > 15%. Multiple regression analysis showed a negative association between PM2.5 exposure and FVC% predicted (− 2.81%, 95% CI − 5.27 to − 0.34%, P = 0.027) and a marginally significant negative correlation with FVC (− 114.38 ml, 95% CI − 230.36 to 1.59 ml, P = 0.053). The remaining pulmonary measures showed a statistically insignificant decline. There were no significant changes in DNA damage detected. Wildland firefighters suffered a significant decline in pulmonary function associated with PM2.5 exposure. Spirometry is crucial for monitoring and promptly identifying respiratory issues that occur during wildfire seasons. Further research is recommended to explore DNA damage alterations and their potential association with PM2.5.

Association between Fine Particulate Matter Exposure and Cerebrospinal Fluid Biomarkers of Alzheimer's Disease among a Cognitively Healthy Population-Based Cohort.

Epidemiological evidence suggests air pollution adversely affects cognition and increases the risk of Alzheimer's disease (AD), but little is known about the biological effects of fine particulate matter (, particulate matter with aerodynamic diameter ) on early predictors of future disease risk. We investigated the association between 1-, 3-, and 5-y exposure to ambient and traffic-related and cerebrospinal fluid (CSF) biomarkers of AD. We conducted a cross-sectional analysis using data from 1,113 cognitively healthy adults (45-75 y of age) from the Emory Healthy Brain Study in Georgia in the United States. CSF biomarker concentrations of , tTau, and pTau, were collected at enrollment (2016-2020) and analyzed with the Roche Elecsys system. Annual ambient and traffic-related residential concentrations were estimated at a and resolution, respectively, and computed for each participant's geocoded address, using three exposure time periods based on specimen collection date. Associations between and CSF biomarker concentrations, considering continuous and dichotomous (dichotomized at clinical cutoffs) outcomes, were estimated with multiple linear/logistic regression, respectively, controlling for potential confounders (age, gender, race, ethnicity, body mass index, and neighborhood socioeconomic status). Interquartile range (IQR; ) increases in 1-y [; 95% confidence interval (CI): , ] and 3-y (; 95% CI: , ) ambient exposures were negatively associated with CSF concentrations. Associations between ambient and were similar for 5-y estimates (; 95% CI: , 0.005). Dichotomized CSF variables revealed similar associations between ambient and . Associations with traffic-related were similar but not significant. Associations between exposures and tTau, pTau , or levels were mainly null. In our study, consistent trends were found between 1-y exposure and decreased CSF , which suggests an accumulation of amyloid plaques in the brain and an increased risk of developing AD. https://doi.org/10.1289/EHP13503.

Effects of fine particulate matter on hospital admission due to stroke in a business city of Thailand

Effects of fine particulate matter on hospital admission due to stroke in a business city of Thailand

Economic effects of air quality on housing prices: evidence from Beijing, China

Air pollution is a major environmental urban issue, particularly in fast-growing cities in developing countries. Reducing air pollution is thus a challenge while evaluating the economic value of air quality is crucial for environmental policies made. However, few studies accurately estimate this value as they neglect the possible endogeneity issues, as well as the dynamic and heterogeneous effects of air pollution. Under the hedonic framework, we therefore assess the economic effect of fine particulate matter (PM2.5) on housing prices in Beijing, China. We construct a panel based on resale apartment transactions matched with average quarterly PM2.5 data between 2013 and 2019. To reduce the risk of an estimation bias, we apply an instrumental variable (IV) approach. Our results show that PM2.5 is negatively associated with housing prices. Households were willing to pay an extra 0.0852% per housing unit price for an average quarterly reduction in PM2.5 of 1 µg/m3. Furthermore, we argue that high-income dwellers tend to pay more for clean air. The negative effects of PM2.5 across regions are significant and different. Compared with that in the basic year 2013, the negative effect increases in the first 3 years and then decreases in the last 3 years. Our findings enhance our comprehension of the economic impact of air quality and make a valuable contribution to the nuanced understanding of willingness to pay for air quality, which is beneficial in assessing and optimizing environmental regulations.

Effects of fine particulate matter on bone mass and osteogenic differentiation of bone marrow mesenchymal stem cells in mice

To observe the effects of exposure to fine particulate matter(PM_(2.5)) on bone mass, microstructure, biomechanical properties, and osteogenic differentiation ability of bone marrow mesenchymal stem cells(BMSCs) in mice. A total of 16 C57BL/6J mice aged 8 weeks were randomly divided into control group(NS group) and PM_(2.5) exposure group(PM group). NS group was given normal saline, PM group was given 14 mg/kg PM_(2.5) suspension, 50 μL, poisoning every 3 day. After 10 weeks, the lungs of mice were taken for HE staining, and the left tibia was taken for Micro CT detection to analyze parameters related to cancellous and cortical bone. The right tibia was taken for HE staining to observe changes in bone trabeculae. Immunohistochemical staining was used to detect type I collagen(Col I), osteoprotegerin(OPG), and nuclear factor-κB receptor activating factor ligand(RANKL) protein expression, tartrate resistant acid phosphatase(TRAP) staining for detection of osteoclasts. Extract primary BMSCs from bilateral femurs, induce osteogenesis, and then perform alkaline phosphatase(ALP) staining to detect ALP activity, alizarin red staining to detect bone mineralization ability, real-time PCR to detect osteocalcin(OCN), ALP, OPG, and RANKL mRNA expression, and biomechanical testing to test the mechanical properties of the femur. Compared with the NS group, the pulmonary alveolar structure of the PM group mice was disrupted and a large number of inflammatory cells gathered. Prompt for successful PM_(2.5) poisoning operation. Micro CT result showed that the bone mineral density(BMD) and bone volume fraction(BV/TV) of the PM group mice were 276.959±15.152 mg/cm~3 and 0.208%±0.009%, respectively. The NS group had 316.709±28.205 mg/cm~3 and 0.236%±0.019%, respectively. The PM group was lower than the NS group(P&lt;0.05), but the trabecular number(Tb. N) There was no statistically significant difference in parameters such as trabecular thickness(Tb. Th) and trabecular separation(Tb. SP)(P&gt;0.05). The HE staining result of the tibia showed that the trabeculae in the NS group were thick, dense, and uniform. The bone trabeculae in the PM group were slender, with a decrease in number, widened spacing, and sparse arrangement. The expression of Col I(0.023±0.009) and OPG(0.036±0.010) in the PM group increased compared to the NS group(0.079±0.007, 0.059±0.012), while the expression of RANKL(0.036±0.006) decreased compared to the NS group(0.022±0.002)(P&lt;0.05); The number of TRAP positive particles increased in the PM group. The experimental result after osteoinduction of BMSCs in mice showed that compared with the NS group, the PM group had a decrease in the number of ALP positive cells and a decrease in the number of calcium nodules. The relative expression of ALP, OCN, and OPG mRNA in the PM group(0.375±0.021, 0.585±0.088, 0.768±0.112) was significantly reduced compared to the NS group(1.001±0.043, 1.006±0.132, 1.002±0.086), while the relative expression of RANKL mRNA(1.278±0.118) was increased compared to the NS group(1.001±0.057)(P&lt;0.05). The biomechanical experimental result showed that the maximum deflection of the NS group was 0.337±0.031 mm, while the maximum deflection of the PM group was 0.258±0.041 mm. Compared with the NS group, the maximum deflection of the PM group decreased significantly(P&lt;0.05), and the maximum stress and maximum load showed a decreasing trend, but the difference was not statistically significant(P&gt;0.05). After 10 weeks of exposure to PM_(2.5), it can affect the bone health of mice, and its mechanism may be related to increased osteoclast activity and inhibition of the osteogenic differentiation ability of BMSCs.

Green space and its types can attenuate the associations of PM2.5 and its components with prediabetes and diabetes—— a multicenter cross-sectional study from eastern China

BackgroundThe effect of fine particulate matter (PM2.5) components on prediabetes and diabetes is of concern, but the evidence is limited and the specific role of different green space types remains unclear. This study aims to investigate the relationship of PM2.5 and its components with prediabetes and diabetes as well as the potential health benefits of different types and combinations of green spaces. MethodsA multicenter cross-sectional study was conducted in eastern China by using a multi-stage random sampling method. Health screening and questionnaires for 98,091 participants were performed during 2017–2020. PM2.5 and its five components were estimated by the inverse distance weighted method, and green space was reflected by the Normalized Difference Vegetation Index (NDVI), percentages of tree or grass cover. Multivariate logistic regression and quantile g-computing were used to explore the associations of PM2.5 and five components with prediabetes and diabetes and to elucidate the potential moderating role of green space and corresponding type combinations in these associations. ResultsEach interquartile range (IQR) increment of PM2.5 was associated with both prediabetes (odds ratio [OR]: 1.15, 95%CI [confidence interval]: 1.10–1.20) and diabetes (OR: 1.18, 95% CI: 1.11–1.25), respectively. All five components of PM2.5 were related to prediabetes and diabetes. The ORs of PM2.5 on diabetes were 1.49 (1.35–1.63) in the low tree group and 0.90 (0.82–0.98) in the high tree group, respectively. In the high tree-high grass group, the harmful impacts of PM2.5 and five components were significantly lower than in the other groups. ConclusionOur study suggested that PM2.5 and its components were associated with the increased risk of prediabetes and diabetes, which could be diminished by green space. Furthermore, the coexistence of high levels of tree and grass cover provided greater benefits. These findings had critical implications for diabetes prevention and green space-based planning for healthy city.

The Cytotoxic Effects of Fine Particulate Matter (PM2.5) from Different Sources at the Air-Liquid Interface Exposure on A549 Cells.

The health of humans has been negatively impacted by PM2.5 exposure, but the chemical composition and toxicity of PM2.5 might vary depending on its source. To investigate the toxic effects of particulate matter from different sources on lung epithelial cells (A549), PM2.5 samples were collected from residential, industrial, and transportation areas in Nanjing, China. The chemical composition of PM2.5 was analyzed, and toxicological experiments were conducted. The A549 cells were exposed using an air-liquid interface (ALI) exposure system, and the cytotoxic indicators of the cells were detected. The research results indicated that acute exposure to different sources of particulate matter at the air-liquid interface caused damage to the cells, induced the production of ROS, caused apoptosis, inflammatory damage, and DNA damage, with a dose-effect relationship. The content of heavy metals and PAHs in PM2.5 from the traffic source was relatively high, and the toxic effect of the traffic-source samples on the cells was higher than that of the industrial- and residential-source samples. The cytotoxicity of particulate matter was mostly associated with water-soluble ions, carbon components, heavy metals, PAHs, and endotoxin, based on the analysis of the Pearson correlation. Oxidative stress played an important role in PM2.5-induced biological toxicity.