Exposure Levels Of PM2 Research Articles

Dynamics of the airway microbiome in response to exposure to particulate matter 2.5 in patients with chronic obstructive pulmonary disease

BackgroundParticulate matter (PM) and air pollution have been suggested to be associated with chronic obstructive pulmonary disease (COPD), contributing significantly to global respiratory disease-related mortality. This study aimed to investigate whether seasonal exposure to PM influences dysbiosis in the respiratory microbiota of patients with COPD. MethodsSputum samples were collected four times over 1 year from 102 patients with COPD, and 16S rRNA sequencing was performed. The dynamics of the airway microbiota were analyzed depending on PM exposure levels and season. ResultsThe PM-low exposure group had higher α-diversity compared to the PM-high exposure group, particularly noted in spring. Some bacterial groups, including seven species such as Treponema socranskii, were more abundant in the low exposure group. Additionally, the bacterial community structure in summer significantly differed from that in other seasons, with significantly increased α-diversity in this season. The difference in the airway microbiome due to PM exposure was prominent in patients with moderate COPD. ConclusionsPM exposure may influence changes in the sputum microbiome depending on exposure levels and seasonal variations. Our results suggest that airway microbiomes could vary with PM exposure according to seasonal trends.

Associations of insulin sensitivity and immune inflammatory responses with child blood lead (Pb) and PM2.5 exposure at an e-waste recycling area during the COVID-19 lockdown.

Fine particular matter (PM2.5) and lead (Pb) exposure can induce insulin resistance, elevating the likelihood of diabetes onset. Nonetheless, the underlying mechanism remains ambiguous. Consequently, we assessed the association of PM2.5 and Pb exposure with insulin resistance and inflammation biomarkers in children. A total of 235 children aged 3-7years in a kindergarten in e-waste recycling areas were enrolled before and during the Corona Virus Disease 2019 (COVID-19) lockdown. Daily PM2.5 data was collected and used to calculate the individual PM2.5 daily exposure dose (DED-PM2.5). Concentrations of whole blood Pb, fasting blood glucose, serum insulin, and high mobility group box 1 (HMGB1) in serum were measured. Compared with that before COVID-19, the COVID-19 lockdown group had lower DED-PM2.5 and blood Pb, higher serum HMGB1, and lower blood glucose and homeostasis model assessment of insulin resistance (HOMA-IR) index. Decreased DED-PM2.5 and blood Pb levels were linked to decreased levels of fasting blood glucose and increased serum HMGB1 in all children. Increased serum HMGB1 levels were linked to reduced levels of blood glucose and HOMA-IR. Due to the implementation of COVID-19 prevention and control measures, e-waste dismantling activities and exposure levels of PM2.5 and Pb declined, which probably reduced the association of PM2.5 and Pb on insulin sensitivity and diabetes risk, but a high level of risk of chronic low-grade inflammation remained. Our findings add new evidence for the associations among PM2.5 and Pb exposure, systemic inflammation and insulin resistance, which could be a possible explanation for diabetes related to environmental exposure.

Particulate Matter Exposure during Pregnancy and Childhood Leukemia Incidence

Leukemia is the most common childhood cancer and its etiology could be related to various environmental contaminants such as particulate matter (PM). The objective of our study is to evaluate the potential association between exposure to PM during pregnancy and the incidence of childhood leukemia. We established a population-based nationwide cohort using the Spanish Birth Registry Statistics database of the National Statistics Institute. We used spatiotemporal land use random forest models to estimate the concentrations of PM10 and PM2.5 for the entire pregnancy and by trimesters. We conducted logistic regression analyses adjusted for various covariates. In addition, we fitted generalized additive models (GAMs) to estimate the non-linear relationship between PM levels and leukemia incidence. The study included 3,112,123 children and 1066 cases of leukemia. The results for the continuous variable of PM10 exposure levels suggested an increased risk of childhood leukemia to be associated with higher exposure. The results for the categorized PM10 variable suggest an increased risk of childhood leukemia among pregnant women whose exposure levels were higher than the median (third and fourth quartiles). The results for PM2.5 were weaker. We found association between exposure to PM10 during pregnancy and an increased risk of childhood leukemia. Our findings indicate that public health interventions should aim to reduce air pollution to lower the incidence of childhood leukemia.

Evaluating air pollution exposure among cyclists: Real-time levels of PM2.5 and NO2 and POI impact

Although cycling has numerous health benefits, the increased breathing volume and lack of protection from exposure to the environment while cycling poses health risks that cannot be disregarded. Previous studies evaluating the exposure of cyclists to air pollution have typically focused on assessing exposure to a single pollutant or exposure concentrations on specific urban routes, and have not performed a comprehensive assessment considering the distribution of cyclists. The present study used bicycle-sharing big data to conduct a more comprehensive and refined real-time population weighted exposure risk assessment of pileless bike sharing riders in Beijing. We quantified the spatial distribution of high exposure areas at different times and found that the exposure risk during the evening peak period was significantly higher than that during the morning peak and early morning periods, particularly in the city center and its environs. By establishing stepwise regression models, we identified the significant impact of various urban points of interest (POIs) on exposure risk, with sports venues, public toilets, educational institutions, scenic spots, and financial entities particularly influential at different time periods. Medical institutions and shopping venues have a significant negative impact on the exposure levels of PM2.5 and NO2 among cyclists in most cases. These findings emphasize the need for targeted pollution control strategies. The aim of this study is to mitigate the impact of air pollution on cyclists and create a healthier cycling environment. The research results can provide new ideas for urban health planning and support scientific decision-making for sustainable urban development.

Specific analysis of PM2.5-attributed disease burden in typical areas of Northwest China.

Frequent air pollution events in Northwest China pose a serious threat to human health. However, there is a lack of specific differences assessment in PM2.5-related disease burden. Therefore, we aimed to estimate the PM2.5-related premature deaths and health economic losses in this typical northwest region, taking into account disease-specific, age-specific, and region-specific factors. We utilized the WRF-Chem model to simulate and analyze the characteristics and exposure levels of PM2.5 pollution in Gansu Province, a typical region of Northwest China. Subsequently, we estimated the premature mortality and health economic losses associated with PM2.5 by combining the Global Exposure Mortality Model (GEMM) and the Value of a Statistical Life (VSL). The results suggested that the PM2.5 concentrations in Gansu Province in 2019 varied spatially, with a decrease from north to south. The number of non-accidental deaths attributable to PM2.5 pollution was estimated to be 14,224 (95% CI: 11,716-16,689), accounting for 8.6% of the total number of deaths. The PM2.5-related health economic loss amounted to 28.66 (95% CI: 23.61-33.63) billion yuan, equivalent to 3.3% of the regional gross domestic product (GDP) in 2019. Ischemic heart disease (IHD) and stroke were the leading causes of PM2.5-attributed deaths, contributing to 50.6% of the total. Older adult individuals aged 60 and above accounted for over 80% of all age-related disease deaths. Lanzhou had a higher number of attributable deaths and health economic losses compared to other regions. Although the number of PM2.5-attributed deaths was lower in the Hexi Corridor region, the per capita health economic loss was higher. Gansu Province exhibits distinct regional characteristics in terms of PM2.5 pollution as well as disease- and age-specific health burdens. This highlights the significance of implementing tailored measures that are specific to local conditions to mitigate the health risks and economic ramifications associated with PM2.5 pollution.

Exposure to particulate matter may affect semen quality via trace metals: Evidence from a retrospective cohort study on fertile males

Particulate matter (PM) exposure may be associated with male semen quality. Besides, PM exposure induces up and down levels of trace metals in tissues or organs. The levels of trace metals in semen are critical for adverse male semen quality. This study aims to evaluate the concentrations of seminal-level trace metals in fertile men and assess its associations with PM exposure and to explore the mediation role of trace metals in seminal plasma plays in the relationship between PM exposure and semen quality. Total 1225 fertile men who participated in a cohort study from 2014 to 2016 were finally recruited. Multivariate linear regression was applied to explore associations between each two of PM exposure, trace metals and semen parameters. 1-year PM2.5 and PM10 exposure levels were positively associated with arsenic (As), mercury (Hg), lanthanum (La), praseodymium (Pr), neodymium (Nd) but negatively associated with vanadium (V), magnesium (Mg), strontium (Sr), barium (Ba) in semen. It was also found that most of the elements were associated with total sperm number, followed by sperm concentration. Redundancy analysis (RDA) also determined several strong positive correlations or negative correlations between 1-year PM exposure and trace metals. Mediation analysis found that trace metals had a potentially compensatory or synergetic indirect effect on the total effect of the association between 1-year PM exposure and semen quality. The retrospective cohort study provides long-term PM exposure that may cause abnormal semen quality by affecting seminal plasma element levels.

Monitoring and Control of Particulate Matter in Urban Area in Douala-Cameroon Town

This study focused on the content of fine particle air pollution in the city of Douala. Several studies have analyzed pollution problems due to road traffic in Douala, Cameroon. Particle concentration levels are higher in heavy traffic than in light traffic. The population’s exposure to air pollution in cities is higher near roads. Several studies have analyzed pollution problems due to road traffic in Douala, Cameroon. In this city, the traffic density at the intersections is indeed higher. Thus, the question is as follows: Are these traffic areas hotspots of increased PM exposure levels? To determine it, four particle size fractions (PM10, PM2.5, PM5, and PM1) were collected using an “OC300 Gas and Dust Particle Laser Detector” for three months at different traffic locations (roundabouts or/and crossroads). Statistical analysis of the data shows very high concentrations at most measurement sites. PM concentrations at the different measurement sites are around 35.69-68.08 µg m−3 for PM1, 50.72-99.13 µg m−3 for PM2.5, 54.11-111.22 µg m−3 for PM5, and 57.97-119.25 µg m−3 for PM10. Exceedances of WHO daily guidelines for PM2.5 (45 µg m−3) and PM10 (15 µg m−3) were found during the measurement campaign, indicating that crossroads are the pollution hotspots in urban areas. Occupation of the roadsides for various economic activities (painting, restaurants, donut shops, etc.) is common in Cameroon, increasing health risks for people working around the roadside. Thus, crossroad locations are areas where the level of exposure to PMx is the highest on road traffics.

Exposure to ambient air pollutants is associated with an increased incidence of hyperuricemia: A longitudinal cohort study among Chinese government employees

BackgroundIt is widely recognized that ambient air pollution can induce various detrimental health outcomes. However, evidence linking ambient air pollutants and hyperuricemia incidence is scarce. ObjectivesTo assess the association between long-term air pollution exposure and the risk of hyperuricemia. MethodsIn this study, a total of 5854 government employees without hyperuricemia were recruited and followed up from January 2018 to June 2021 in Hunan Province, China. Hyperuricemia was defined as serum uric acid (SUA) level of >420 μmol/L for men and >360 μmol/L for women or use of SUA-lowering medication or diagnosed as hyperuricemia during follow-up. Data from local air quality monitoring stations were used to calculate individual exposure levels of PM10, PM2.5, SO2 and NO2 by inverse distance weightingn (IDW) method. Cox proportional hazard model was applied to evaluate the causal relationships between air pollutant exposures and the risk of hyperuricemia occurrence after adjustment for potential confounders and meanwhile, restricted cubic spline was used to explore the dose-response relationships. ResultsThe results indicated that exposures to PM10 (hazard ratio, HR = 1.042, 95% conficence interal, 95% CI: 1.028, 1.057), PM2.5 (HR = 1.204, 95% CI: 1.141, 1.271) and NO2 (HR = 1.178, 95% CI: 1.125,1.233) were associated with an increased HR of hyperuricemia. In addition, a nonlinear dose-response relationship was found between PM10 exposure level and the HR of hyperuricemia (p for nonlinearity = 0.158) with a potential threshold of 50.11 μg/m3. Subgroup analysis demonstrated that participants usually waking up at night and using natural ventilation were more vulnerable to the exposures of PM10, PM2.5, NO2, and SO2. ConclusionLong-term exposures to ambient PM10, PM2.5 and NO2 are associated with an increased incidence of hyperuricemia among Chinese government employees.

Association of air pollution with olfactory identification performance of São Paulo residents: a cross-sectional study.

Exposure to particulate matter of 10μm or less in diameter (PM10) has been implicated in pulmonary and cardiovascular diseases. However, the effect of PM10 on olfaction has not been well established. We estimated individual acute and chronic PM10 exposure levels in a large Brazilian cohort and related them to the ability to identify odors. Adults from São Paulo (n = 1358) were recruited from areas with different levels of air pollution. To verify individual exposure to air pollution, the averages of 30, 60, 90, 180 and 364days of PM10 were interpolated to subjects' zip codes using the kriging method. Olfactory identification performance was tested using the University of Pennsylvania Smell Identification Test (UPSIT®). Multiple linear regressions were used to calculate the effect of air pollution on olfactory identification performance, controlling for demographic and other variables that affect the sense of smell. Acute exposures to PM10 were related to worse UPSIT® scores, including 30- (β = - 0.94, 95% Confidence Interval [CI] - 0.98, - 0.89), 60- (β = - 1.09, 95% CI = - 1.13, - 1.04) and 90-day intervals (β = - 1.06, 95% CI - 1.10, - 1.02) (reference for β: 1µm/m3 increase in PM10 exposure per point decrease in UPSIT® score). Chronic exposures were also associated with worse olfaction for both 180- (β = - 1.06, 95% CI - 1.10, - 1.03) and 364-day (β = - 0.87, 95% CI - 0.90, - 0.84) intervals. As in prior work, men, older, low-income, and low-schooling people demonstrated worse olfactory performance. Acute and chronic exposure to PM10 is strongly associated with olfactory identification performance in Brazilian adults. Understanding the mechanisms which underlie these relationships could help to improve chemosensory function with a large public health impact.

Impact of Air Pollutants and Pollen on the Severity of Nonallergic Rhinitis: A Data-Oriented Analysis.

BackgroundRhino-conjunctivitis symptoms are more severe in nonallergic rhinitis (NAR) patients during pollen season than in other seasons. Little is known about the role of pollen and air pollutants on the severity of NAR.ObjectiveThe aim of this study is to assess the cross-sectional effects of both pollen and air pollutants on NAR patients during the pollen and non-pollen seasons, and to further explore the possible relationship among these triggers.MethodsA total of 2411 clinically diagnosed NAR outpatients from 2018 to 2019 were recruited for this study. The severity of NAR was measured using rhinoconjunctivitis symptom scores. Associations of daily exposure to pollen, PM2.5, PM10, NO2, SO2, CO, O3, and rhinoconjunctivitis symptom scores were evaluated using Logistic regression models. Distributed Lag Nonlinear models were used to explore single-day and accumulative Lag effects of environmental factors mentioned above.ResultsDuring the pollen season, pollen concentration, higher exposure levels of PM10, PM2.5, NO2, and SO2 increased the severity of NAR group when compared with the low-moderate severity group. The high severity group was associated with lower exposure levels of O3. However, during non-pollen seasons, no significant association was found in air pollutant metrics, pollen concentration, and severity of NAR. The exposure-severity effects of pollen were different when different ambient pollutants were stratified.ConclusionSynergistic effect of pollen and air pollutants, including PM2.5, PM10, SO2, NO2, and O3, might be responsible for aggravating the symptoms of NAR patients during pollen seasons.

Exposure to PM2.5 and PM10 and COVID-19 infection rates and mortality: A one-year observational study in Poland

BackgroundAtmospheric contamination, especially particulate matter (PM), can be associated viral infections connected with respiratory failure. Literature data indicates that intensity of SARS-CoV-2 infections worldwide can be associated with PM pollution levels. ObjectivesThe aim of the study was to examine the relationship between atmospheric contamination, measured as PM2.5 and PM10 levels, and the number of COVID-19 cases and related deaths in Poland in a one-year observation study. MethodsNumber and geographical distribution of COVID-19 incidents and related deaths, as well as PM2.5 and PM10 exposure levels in Poland were obtained from publicly accessible databases. Average monthly values of these parameters for individual provinces were calculated. Multiple regression analysis was performed for the period between March 2020 and February 2021, taking into account average monthly exposure to PM2.5 and PM10, monthly COVID-19 incidence and mortality rates per 100,000 inhabitants and the population density across Polish provinces. ResultsOnly December 2020 the number of new infections was significantly related to the three analyzed factors: PM2.5, population density and the number of laboratory COVID-19 tests (R2 = 0.882). For COVID-19 mortality, a model with all three significant factors: PM10, population density and number of tests was obtained as significant only in November 2020 (R2 = 0.468). ConclusionThe distribution of COVID-19 incidents across Poland was independent from annual levels of particulate matter concentration in provinces. Exposure to PM2.5 and PM10 was associated with COVID-19 incidence and mortality in different provinces only in certain months. Other cofactors such as population density and the number of performed COVID-19 tests also corresponded with both COVID-19-related infections and deaths only in certain months. Particulate matter should not be treated as the sole determinant of the spread and severity of the COVID-19 pandemic but its importance in the incidence of infectious diseases should not be forgotten.

Effects of Air Pollutant Exposure on Exacerbation Severity in Asthma Patients with or without Reversible Airflow Obstruction.

BackgroundReversible airflow obstruction (RO) and fixed airflow obstruction (FO) are two important clinical phenotypes of asthma. However, the relationship between air pollutant exposure and exacerbation of the two phenotypes is unknown.ObjectiveTo study the effects of air pollutant exposure on exacerbation severity in asthma patients with or without FO.MethodsA total of 197 severe asthma patients were enrolled, and divided into two groups: the FO group (n=81) and the RO group (n=116). We collected the demographic data, laboratory parameters, pulmonary function test parameters, and the daily average concentrations of different air particles in Shenzhen on the different lag days of each subject. The receiver operating characteristic (ROC) curve was used to identify the effects of major air pollutants on the severity of asthma patients with RO.ResultsCompared with the RO group, the FO group had fewer women, lower body mass index (BMI), longer disease duration, higher smoking history rate, allergic family history rate, FeNO level, and lower levels of large airway parameters. The median exposure levels of PM10 and PM2.5 in the severe RO subgroup were both higher than those in the mild-to-moderate RO subgroup on Lag0, 1 and 3, and the median exposure level of PM1 on Lag0 in the severe RO subgroup was significantly higher than that in the mild-to-moderate RO subgroup. Logistic regression modeling indicated exposure to PM2.5 and PM1.0 on Lag0, and PM10 on Lag0-2 were the independent risk factors for hospital admissions for asthma patients with RO. By performing an ROC curve analysis, PM2.5 on Lag0 (AUC = 0.645, p = 0.027) provided a best performance to predict severe asthma exacerbations with RO, with a sensitivity of 36.0% and a specificity of 91.2%.ConclusionShort-term exposure to PM10, PM2.5 and PM1 may play a role in exacerbation severity among asthma patients with RO.

Prenatal exposure to PM10 and changes in DNA methylation and telomere length in cord blood

BACKGROUND AND AIM: Air pollution exposure in pregnancy can cause molecular level alterations associated with later disease susceptibility. We aimed to investigate changes in two molecular marker types, DNA methylation and telomere length, in cord blood in relation to gestational PM10 exposure and to explore potential gestational windows of susceptibility. METHODS: Cord blood epigenome-wide DNA methylation (N=384) and telomere length (N=500) were measured in children of the Italian birth cohort Piccolipiù using the Infinium Methylation EPIC BeadChip (Illumina) and qPCR, respectively. PM10 exposure levels were estimated for different gestational periods based on maternal residential address, using advanced methods based on satellite data. Lag distributed models using weekly exposures were used to further confirm the identified exposure windows. RESULTS:PM10 exposure during the first gestational weeks was associated with DNA methylation of more than 100 unique CpGs, mapped to genes with relevant functions in cell replication, differentiation and response to environmental stressors. We were able to test half of the CpGs in an independent sample from the same cohort and six CpGs showed robust associations. PM10 exposure during mid and later pregnancy was associated with shorter and longer telomeres, respectively. CONCLUSIONS:The first weeks of pregnancy seems to be a particularly important PM10 exposure window for DNA methylation that should be accounted for in future analyses, while exposure to PM10 in mid and late pregnancy might be important for telomere length. DNA methylation and telomere length are fundamental regulators of cellular processes during early life, and their alterations could have major implications for later disease susceptibility. KEYWORDS: Environmental epidemiology, Particulate matter, Epigenomics, Telomere length

Occupational exposure to fine particulate matter (PM4 and PM2.5) during artisanal cookware manufacturing: personal, indoor and outdoor levels

Background: Occupational exposure to fine particulate matter is associated with adverse respiratory, cardiovascular and pregnancy outcomes. Artisanal cookware manufacturing involves preparing sand molds for casting and a smelting process to cast liquid aluminium melted from a collection of scrap metal. Objective: The aim of this study was to characterize occupational exposure to fine particulate matter (PM4 and PM2.5) during artisanal cookware manufacturing, and to examine the relationship between personal, indoor and outdoor PM levels. Methods: Exposure to fine particulate matter was measured for 17 male participants across five artisanal cookware manufacturing sites during the winter season. SidePak personal aerosol monitors (AM520) were used to measure personal exposure to PM4, while a DustTrak monitor and an E-sampler were used to assess indoor and outdoor PM2.5 levels, respectively. Personal measurements were undertaken for a period of 3 hours per participant. Indoor and outdoor sampling was performed for a period of 8 hours for each site. A questionnaire was administered face-to-face by field workers to capture information on demographic characteristics. Spearman’s correlation coefficient between personal, indoor and outdoor levels was used. Time series record of 15-min averages for indoor and outdoor PM2.5 levels were assessed. Results: Personal PM exposure levels at breathing zones of workers exceeded environmental levels. The mean (SD) was 490 µg/m3 (3520), 150 µg/m3 (390) and 20 µg/m3 (50), respectively for personal PM4, indoor and outdoor PM2.5. Time series analysis showed higher indoor than outdoor PM levels with little evidence of elevated outdoor PM sources. In most cases, there were somewhat low correlations between personal, indoor and outdoor PM measurements. Correlation was higher between PM and meteorological factors in some of the sites. Conclusions: The levels of fine particulate exposure among artisanal cookware makers were elevated, especially in respect of personal breathing zone measurements.

Exposure to particulate matter and risk of conversion from mild cognitive impairment to dementia: a cohort study in a Northern Italy population

Background/Aim Exposure to air pollutants such as inhalable particulate matter has been linked to increased risk of chronic disease including neurodegenerative diseases, such as Alzheimer’s dementia. In this study, we aimed to evaluate the effect of long-term exposure to outdoor air pollution, and specifically to particulate matter ≤10 μm (PM10), on the risk of dementia in a cohort of subjects with mild cognitive impairment. MethodsWe recruited 53 subjects newly-diagnosed with mild cognitive impairment of non-vascular origin and residing in the Modena and Reggio Emilia provinces of Northern Italy. Using a Geographical Information System and a validated air pollution dispersion model, we assessed exposure to outdoor PM10 from motorized traffic at subjects’ residence. We investigated the relation of these concentrations to subsequent onset of dementia, using a Cox proportional hazards model. We computed hazard ratio (HR) and 95% confidence interval (CI) according to fixed categories of PM10 exposure, adjusting for sex, age, and educational attainment level. ResultsDuring a median follow-up of 42 months, 19 participants developed Alzheimer’s dementia, 3 frontotemporal dementia and 2 Lewy body dementia. Baseline PM10 exposure levels were 9.6 µg/m3 on average. Using PM10 levels below 5 µg/m3 as reference, we found a dose-response increase in any dementia risk with HR of 1.04 (95% CI 0.41-2.66) at 5-10 µg/m3, 1.32 (95% CI 0.36-4.92) at 10-20 µg/m3, and 1.38 (95% CI 0.14-13.13) above 20 µg/m3, respectively. Conclusions Our results suggest that exposure to particulate matter emitted by motorized vehicles increases the risk of conversion from mild cognitive impairment to dementia, though the low number of study participants suggests caution in the interpretation of these findings.

The Effects of Social, Personal, and Behavioral Risk Factors and PM2.5 on Cardio-Metabolic Disparities in a Cohort of Community Health Center Patients.

(1) Background: Cardio-metabolic diseases (CMD), including cardiovascular disease, stroke, and diabetes, have numerous common individual and environmental risk factors. Yet, few studies to date have considered how these multiple risk factors together affect CMD disparities between Blacks and Whites. (2) Methods: We linked daily fine particulate matter (PM2.5) measures with survey responses of participants in the Southern Community Cohort Study (SCCS). Generalized linear mixed modeling (GLMM) was used to estimate the relationship between CMD risk and social-demographic characteristics, behavioral and personal risk factors, and exposure levels of PM2.5. (3) Results: The study resulted in four key findings: (1) PM2.5 concentration level was significantly associated with reported CMD, with risk rising by 2.6% for each µg/m3 increase in PM2.5; (2) race did not predict CMD risk when clinical, lifestyle, and environmental risk factors were accounted for; (3) a significant variation of CMD risk was found among participants across states; and (4) multiple personal, clinical, and social-demographic and environmental risk factors played a role in predicting CMD occurrence. (4) Conclusions: Disparities in CMD risk among low social status populations reflect the complex interactions of exposures and cumulative risks for CMD contributed by different personal and environmental factors from natural, built, and social environments.

Association of Ambient Particulate Matter Exposure with the Incidence of Glaucoma in Childhood

We investigated whether exposure to air pollution, particularly to particles with a mass median aerodynamic diameter of ≤10μm (PM10), is associated with diagnosis of childhood glaucoma. Retrospective cohort study. From the National Health Insurance Service-National Sample Cohort, a total of 9004 infants born between January 2002 and December 2002 were included and followed-up for an 11-year period (2003-2012). Patients with glaucoma were defined as International Classification of Diseases, 10th revision code H40. Exposure levels of PM10 were extrapolated using geographic information systems, and individual exposure levels were assigned. During the study period, glaucoma occurred in 85 patients (0.94%). The probability of developing childhood glaucoma increased with the increase in PM10 quartiles. Increases in 1μg/m3 of long-term PM10 were significantly associated with increased hazard ratios (HRs) for childhood glaucoma (HR= 1.22 [95% confidence interval {CI} 1.15-1.28]). Compared with risk of the lowest PM10 exposure group (quartile 1), the adjusted HRs for childhood glaucoma were significant in the highest PM10 exposure group of quartile 4 (HR= 2.84 [95% CI 1.37-5.89]) in model 3. Regarding the long-term PM10 exposure, the estimated hazard was considerably elevated in quartile 4 (HR= 6.61 [95% CI 2.96-14.75]). Short-term and long-term exposure to PM10 was associated with the incidence of childhood glaucoma. This finding confirms previous reports on the link between air pollution and ocular disease and suggests that PM10 exposure may be a risk for childhood glaucoma.

Effects of prenatal exposure to air particulate matter on the risk of preterm birth and roles of maternal and cord blood LINE-1 methylation: A birth cohort study in Guangzhou, China

BackgroundEpidemiological studies have found that increased risk of preterm birth (PTB) is associated with higher prenatal exposure to PM10 and PM2.5, but few studies have been conducted to assess the impacts of extremely fine particulate matter (PM1) which may have more toxic effects than other types of ambient particulate air pollution (PM). Several studies have separately investigated the associations between DNA methylation and PTB risk and PM. Maternal LINE-1 methylation level negatively correlated with prenatal exposure to PM and risk of PTB. A comprehensive picture is lacking regarding the associations between prenatal exposure to PM, LINE-1 methylation, and risk of PTB. ObjectivesThis study aimed to estimate the effects of exposure to ambient PM (PM10, PM2.5, and PM1) of different sizes during pregnancy on risk of PTB, identify susceptible exposure windows, and illustrate the roles of LINE-1 methylation in the associations between PM and PTB risk. MethodsThe Birth Cohort Study on Prenatal Environments and Offspring Health (PEOH) has been ongoing since 2016 in Guangzhou, China. A total of 4928 pregnant women were recruited during early pregnancy, and 4278 (86.8%) were successfully followed-up. Each individual weekly exposure to PM10 and PM2.5 from 3 months before pregnancy to childbirth was assessed using a spatiotemporal land use regression model, and the weekly PM1 exposure was estimated by employing a generalized additive model. Maternal and cord blood LINE-1 methylation levels (%5mC) were tested using bisulfite-PCR pyrosequencing. A distributed lag nonlinear model incorporated with a Cox proportional hazard model was applied to assess the effect of weekly-specific maternal PM exposure on PTB risk, and a multiple-linear regression model was employed to investigate the associations between PM exposure and LINE-1 methylation levels of maternal and cord bloods. We also assessed the associations between LINE-1 methylation levels and PTB risk by using a logistic regression model. ResultsThe risk of PTB was positively associated with PM2.5 and PM1 concentrations during the 12th to 20th gestational weeks, and the strongest association was in the fourth quartile (Q4) versus the first quartile (Q1) and observed during the 16th gestational week (PM2.5: harzard ratio [HR] = 1.18, 95%CI: 1.04–1.35, IQR = 11.94 μg/m3. PM1: HR = 1.20, 95%CI: 1.03–1.39, IQR = 11.36 μg/m3). We observed significantly negative associations of PM10(β = −0.51%5mC per 10 μg/m3, P = 0.014), PM2.5 (β = −0.66%5mC per 10 μg/m3, P = 0.032) and PM1 (β = −0.67%5mC per 10 μg/m3, P = 0.032) concentrations with cord blood LINE-1 methylation levels, and a negative association between PM1 concentration and maternal LINE-1 methylation level (β = −0.86%5mC per 10 μg/m3, P = 0.034). ConclusionHigher prenatal exposure to PM1 and PM2.5 during the 12th to 20th gestational weeks was associated with increased risk of PTB. Maternal and fetal LINE-1 methylation alternation might be an underlying mechanism of PM that increasing the risk of PTB.

Exposure to ambient PM10 and NO2 and the incidence of attention-deficit hyperactivity disorder in childhood

BackgroundEpidemiological studies have implicated air pollution in the causation of neurodevelopmental disorders, including attention-deficit hyperactivity disorder (ADHD), but definitive evidence of this linkage is lacking. ObjectivesWe examined the association between cumulative exposure to air pollutants from birth to diagnosis, particularly particulate matter of <10μm (PM10) and nitric dioxide (NO2), and childhood ADHD. MethodsWe used the National Health Insurance Service-National Sample Cohort (2002−2012), a population-wide health insurance claims dataset. A total of 8936 infants (age 0) born between January 2002 and December 2002 were followed-up for a 10-year period (2003−2012). ADHD was defined as per ICD-10 code F90.0. Exposure levels of PM10 and NO2 were extrapolated using geographic information systems and collated with the subjects' administrative district code, and individual exposure levels assigned. Hazard ratios (HRs) were calculated for the development of ADHD, after adjusting for gender, metropolitan area, income, and history of diseases. ResultsDuring the study period, ADHD occurred in 314 subjects (3.5%). With the increase in 1μg/m3 of air pollutants, the HRs of childhood ADHD were 1.18 (95% CI: 1.15–1.21) in case of PM10 and 1.03 (95% CI: 1.02–1.04) in case of NO2. Compared with infants with the lowest tertile of PM10 or NO2 exposure, those with the highest tertile of PM10 (HR=3.88; 95% CI: 2.87–5.23) or NO2 (HR=2.10; 95% CI, 1.54–2.85) exposure had a 2 to 3 fold increased risk for ADHD. ConclusionExposure to PM10 and NO2 was associated with the incidence of ADHD in childhood.

The burden of lung cancer mortality attributable to fine particles in China.

Although studies have examined the associations between fine particles (PM2.5) and lung cancer mortality in US and European countries, the evidence is still limited for China. In addition, no study has provided estimates of spatial variation in lung cancer mortality attributable to PM2.5 in China. In this study, we quantified the associations between lung cancer mortality and PM2.5, using a spatiotemporal model with observed data of lung cancer mortality from 75 communities from the National Cancer Registration of China from 1990 to 2009 and the annual concentrations of PM2.5 at 0.5°×0.5° spatial resolution. We also estimated lung cancer mortality burden attributable to PM2.5 in China, with predicted county level lung cancer deaths in 2005. We found that the PM2.5-lung cancer mortality associations were non-linear, with thresholds of 40μg/m3 overall, 45μg/m3 for male, 42μg/m3 for female, 45μg/m3 for those aged 30-64years, 48μg/m3 for those aged 65-74years, and 40μg/m3 for those aged 75years and more, above which the relative risks were 1.08 (95% CI: 1.07, 1.09), 1.07 (95% CI: 1.05, 1.08), 1.12 (95% CI: 1.1, 1.14), 1.05 (95% CI: 1.04, 1.07), 1.07 (95% CI: 1.06, 1.09), and 1.14 (95% CI: 1.12, 1.16) respectively. There were 51,219 (95% CI: 45,745-56,512) lung cancer deaths attributed to PM2.5 in 2005, with attributable fractions of 13.7% (95% CI: 12.23-15.11%) overall, 10.01% (95% CI: 8.37-11.58%) for men, 18.06% (95% CI: 15.81-20.18%) for women, 8.35% (95% CI: 6.07-10.51%) for those aged 65-74years, 9.73% (95% CI: 7.6-11.75%) for those aged 65-74years, 21.7% (95% CI: 19.27-23.99%) for those aged 75years or more. In conclusion, assuming a causal relation a reduction in exposure levels of PM2.5 below thresholds would avert a substantial number of deaths from lung cancer in China.