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1.
Environ Res ; 185: 109360, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32222629

RESUMO

Ambient particulate matter (PM) is a leading global environmental health risk. Current air quality regulations are based on airborne mass concentration. However, PM from different sources have distinct chemical compositions and varied toxicity. Connections between emission control measures, air quality, PM composition, and toxicity remain insufficiently elucidated. The current study assessed the composition and toxicity of PM collected in Nanjing, China before, during, and after an air quality intervention for the 2014 Youth Olympic Games. A co-culture model that mimics the alveolar epithelium with the associated macrophages was created using A549 and THP-1 cells. These cells were exposed to size-segregated inhalable PM samples. The composition and toxicity of the PM samples were influenced by several factors including seasonal variation, emission sources, and the air quality intervention. For example, we observed a size-dependent shift in particle mass concentrations during the air quality intervention with an emphasized proportion of smaller particles (PM2.5) present in the air. The roles of industrial and fuel combustion and traffic emissions were magnified during the emission control period. Our analyses revealed that the PM samples demonstrated differential cytotoxic potencies at equal mass concentrations between sampling periods, locations, and time of day, influenced by variations in the predominant emission sources. Coal combustion and industrial emissions were the most important sources affecting the toxicological responses and displayed the least variation in emission contributions between the sampling periods. In conclusion, emission control mitigated cytotoxicity and oxidative stress for particles larger than 0.2 µm, but there was inadequate evidence to determine if it was the key factor reducing the harmful effects of PM0.2.

2.
Hypertension ; 75(2): 347-355, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31838909

RESUMO

Evidence on the associations between airborne particulates of diameter ≤1 µm (PM1) and airborne particulates of diameter ≤2.5 µm (PM2.5) and childhood blood pressure (BP) is scarce. To help to address this literature gap, we conducted a study to explore the associations in Chinese children. Between 2012 and 2013, we recruited 9354 children, aged 5 to 17 years, from 62 schools in 7 northeastern Chinese cities. We measured their BP with a mercury sphygmomanometer. We used a spatiotemporal model to estimate daily ambient PM1 and PM2.5 exposures, which we assigned to participants' home addresses. Associations between particulate matter exposure and BP were evaluated with generalized linear mixed regression models. The findings indicated that exposure to each 10 mg/m3 greater PM1 was significantly associated with 2.56 mm Hg (95% CI, 1.47-3.65) higher systolic BP and 61% greater odds for hypertension (odds ratio=1.61 [95% CI, 1.18-2.18]). PM1 appears to play an important role in associations reported between PM2.5 exposure and BP, and we found that the ambient PM1/PM2.5 ratio (range, 0.80-0.96) was associated with BP and with hypertension. Age and body weight modified associations between air pollutants and BP (P<0.01), with stronger associations among younger (aged ≤11 years) and overweight/obese children. This study provides the first evidence that long-term exposure to PM1 is associated with hypertension in children, and that PM1 might be a leading contributor to the hypertensive effect of PM2.5. Researchers and policy makers should pay closer attention to the potential health impacts of PM1.

3.
Environ Pollut ; 256: 113434, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31672350

RESUMO

BACKGROUND: Little information exists on interaction effects between air pollution and influenza vaccination on allergic respiratory diseases. We conducted a large population-based study to evaluate the interaction effects between influenza vaccination and long-term exposure to ambient air pollution on allergic respiratory diseases in children and adolescents. METHODS: A cross-sectional study was investigated during 2012-2013 in 94 schools from Seven Northeastern Cities (SNEC) in China. Questionnaires surveys were obtained from 56 137 children and adolescents aged 2-17 years. Influenza vaccination was defined as receipt of the influenza vaccine. We estimated air pollutants exposure [nitrogen dioxide (NO2) and particulate matter with aerodynamic diameters ≤1 µm (PM1), ≤2.5 µm (PM2.5) and ≤10 µm (PM10)] using machine learning methods. We employed two-level generalized linear mix effects model to examine interactive effects between influenza vaccination and air pollution exposure on allergic respiratory diseases (asthma, asthma-related symptoms and allergic rhinitis), after controlling for important covariates. RESULTS: We found statistically significant interactions between influenza vaccination and air pollutants on allergic respiratory diseases and related symptoms (doctor-diagnosed asthma, current wheeze, wheeze, persistent phlegm and allergic rhinitis). The adjusted ORs for doctor-diagnosed asthma, current wheeze and allergic rhinitis among the unvaccinated group per interquartile range (IQR) increase in PM1 and PM2.5 were significantly higher than the corresponding ORs among the vaccinated group [For PM1, doctor-diagnosed asthma: OR: 1.89 (95%CI: 1.57-2.27) vs 1.65 (95%CI: 1.36-2.00); current wheeze: OR: 1.50 (95%CI: 1.22-1.85) vs 1.10 (95%CI: 0.89-1.37); allergic rhinitis: OR: 1.38 (95%CI: 1.15-1.66) vs 1.21 (95%CI: 1.00-1.46). For PM2.5, doctor-diagnosed asthma: OR: 1.81 (95%CI: 1.52-2.14) vs 1.57 (95%CI: 1.32-1.88); current wheeze: OR: 1.46 (95%CI: 1.21-1.76) vs 1.11 (95%CI: 0.91-1.35); allergic rhinitis: OR: 1.35 (95%CI: 1.14-1.60) vs 1.19 (95%CI: 1.00-1.42)]. The similar patterns were observed for wheeze and persistent phlegm. The corresponding p values for interactions were less than 0.05, respectively. We assessed the risks of PM1-related and PM2.5-related current wheeze were decreased by 26.67% (95%CI: 1.04%-45.66%) and 23.97% (95%CI: 0.21%-42.08%) respectively, which was attributable to influenza vaccination (both p for efficiency <0.05). CONCLUSIONS: Influenza vaccination may play an important role in mitigating the detrimental effects of long-term exposure to ambient air pollution on childhood allergic respiratory diseases. Policy targeted at increasing influenza vaccination may yield co-benefits in terms of reduced allergic respiratory diseases.


Assuntos
Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Doenças Respiratórias/epidemiologia , Adolescente , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Asma/epidemiologia , Criança , Pré-Escolar , China , Cidades , Estudos Transversais , Feminino , Humanos , Hipersensibilidade/epidemiologia , Influenza Humana , Modelos Logísticos , Masculino , Dióxido de Nitrogênio , Material Particulado/análise , Transtornos Respiratórios , Sons Respiratórios , Fatores de Risco , Instituições Acadêmicas , Inquéritos e Questionários , Vacinação
4.
Environ Pollut ; 256: 113422, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31672364

RESUMO

Evidence suggests that residential greenness may be protective of high blood pressure, but there is scarcity of evidence on the associations between greenness around schools and blood pressure among children. We aimed to investigate this association in China. Our study included 9354 children from 62 schools in the Seven Northeastern Cities Study. Greenness around each child's school was measured by NDVI (Normalized Difference Vegetation Index) and SAVI (Soil-Adjusted Vegetation Index). Particulate matter ≤ 1 µm (PM1) concentrations were estimated by spatiotemporal models and nitrogen dioxide (NO2) concentrations were collected from air monitoring stations. Associations between greenness and blood pressure were determined by generalized linear and logistic mixed-effect models. Mediation by air pollution was assessed using mediation analysis. Higher greenness was consistently associated with lower blood pressure. An increase of 0.1 in NDVI corresponded to a reduction in SBP of 1.39 mmHg (95% CI: 1.86, -0.93) and lower odds of hypertension (OR = 0.76, 95% CI: 0.69, 0.82). Stronger associations were observed in children with higher BMI. Ambient PM1 and NO2 mediated 33.0% and 10.9% of the association between greenness and SBP, respectively. In summary, greater greenness near schools had a beneficial effect on blood pressure, particularly in overweight or obese children in China. The associations might be partially mediated by air pollution. These results might have implications for policy makers to incorporate more green space for both aesthetic and health benefits.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Hipertensão/epidemiologia , Desenvolvimento Sustentável , Poluição do Ar/análise , Poluição do Ar/estatística & dados numéricos , Pressão Sanguínea , Criança , China/epidemiologia , Cidades , Feminino , Humanos , Masculino , Dióxido de Nitrogênio/análise , Obesidade , Material Particulado/análise , Risco , Instituições Acadêmicas
5.
Sci Total Environ ; 702: 135040, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31726339

RESUMO

Living in greener places may protect against obesity, but epidemiological evidence is inconsistent and mainly comes from developed nations. We aimed to investigate the association between greenness and obesity in Chinese adults and to assess air pollution and physical activity as mediators of the association. We recruited 24,845 adults from the 33 Communities Chinese Health Study in 2009. Central and peripheral obesity were defined by waist circumference (WC) and body mass index (BMI), respectively, based on international obesity standards. The Normalized Difference Vegetation Index (NDVI) was used to quantify community greenness. Two-level logistic and generalized linear mixed regression models were used to evaluate the association between NDVI and obesity, and a conditional mediation analysis was used also performed. In the adjusted models, an interquartile range increase in NDVI500-m was significantly associated with lower odds of peripheral 0.80 (95% confidence interval [CI]: 0.74-0.87) and central obesity 0.88 (95% CI: 0.83-0.93). Higher NDVI values were also significantly associated with lower BMI. Age, gender, and household income significantly modified associations between greenness and obesity, with stronger associations among women, older participants, and participants with lower household incomes. Air pollution mediated 2.1-20.8% of the greenness-obesity associations, but no mediating effects were observed for physical activity. In summary, higher community greenness level was associated with lower odds of central and peripheral obesity, especially among women, older participants, and those with lower household incomes. These associations were partially mediated by air pollutants. Future well-designed longitudinal studies are needed to confirm our findings.


Assuntos
Obesidade/epidemiologia , Desenvolvimento Sustentável , Poluição do Ar , Índice de Massa Corporal , China/epidemiologia , Cidades/epidemiologia , Exercício , Humanos , Características de Residência , Fatores Socioeconômicos , População Urbana/tendências
6.
JAMA Netw Open ; 2(5): e194186, 2019 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-31125097

RESUMO

Importance: Breastfeeding and exposure to ambient air pollutants have been found to be independently associated with respiratory health in children; however, previous studies have not examined the association of breastfeeding as a potential moderator of the association. Objective: To assess associations of breastfeeding and air pollution with lung function in children. Design, Setting, and Participants: Using a cross-sectional study design, children were recruited from 62 elementary and middle schools located in 7 Chinese cities from April 1, 2012, to October 31, 2013. Data analyses were conducted from November 1, 2018, to March 31, 2019. Exposures: Long-term concentrations of airborne particulate matter with a diameter of 1 µm or less (PM1), airborne particulate matter with a diameter of 2.5 µm or less (PM2.5), airborne particulate matter with a diameter of 10 µm or less (PM10), and nitrogen dioxide were estimated using a spatial statistical model matched to children's geocoded home addresses, and concentrations of PM10, sulfur dioxide, nitrogen dioxide, and ozone were measured by local air monitoring stations. Main Outcomes and Measures: Breastfeeding was defined as maternal report of having mainly breastfed for longer than 3 months. Lung function was measured using portable electronic spirometers. Using previously published predicted spirometric values for children in Northeast China as the reference, lung impairment was defined as forced vital capacity (FVC) less than 85%, forced expiratory volume in the first second of expiration less than 85%, peak expiratory flow less than 75%, or maximum midexpiratory flow less than 75%. Results: Participants included 6740 children (mean [SD] age, 11.6 [2.1] years; 3382 boys [50.2%]). There were 4751 children (70.5%) who were breastfed. Mean (SD) particulate matter concentrations ranged from 46.8 (6.5) µg/m3 for PM1 to 95.6 (9.8) µg/m3 for PM10. The prevalence of lung function impairment ranged from 6.8% for peak expiratory flow to 11.3% for FVC. After controlling for age, sex, and other covariates, 1-interquartile range greater concentration of pollutants was associated with higher adjusted odds ratios (AORs) for lung function impairment by FVC among children who were not breastfed compared with those who were (PM1: AOR, 2.71 [95% CI, 2.02-3.63] vs 1.20 [95% CI, 0.97-1.48]; PM2.5: AOR, 2.27 [95% CI, 1.79-2.88] vs 1.26 [95% CI, 1.04-1.51]; and PM10: AOR, 1.93 [95% CI, 1.58-2.37] vs 1.46 [95% CI, 1.23-1.73]). Younger age (<12 years) was associated with lower lung function impairment among the children who had been breastfed. In children from elementary schools, 1-interquartile range greater concentration of pollutants was associated with higher AORs for lung function impairment by FVC among children who had not been breastfed compared with those who had (PM1: AOR, 6.43 [95% CI, 3.97-10.44] vs 1.89 [95% CI, 1.28-2.80]; PM2.5: AOR, 3.83 [95% CI, 2.63-5.58] vs 1.50 [95% CI, 1.12-2.01]; and PM10: AOR, 2.61 [95% CI, 1.90-3.57] vs 1.52 [95% CI, 1.19-1.95]). Results from linear regression models also showed associations of air pollution with worse lung function among children who were not breastfed compared with their counterparts who were breastfed, especially for FVC (PM1: ß, -240.46 [95% CI, -288.71 to -192.21] vs -38.21 [95% CI, -69.27 to -7.16] mL) and forced expiratory volume in the first second of expiration (PM1: ß, -201.37 [95% CI, -242.08 to -160.65] vs -30.30 [95% CI, -57.66 to -2.94] mL). Conclusions and Relevance: In this study, breastfeeding was associated with lower risk of lung function impairment among children in China exposed to air pollution, particularly among younger children.


Assuntos
Poluição do Ar/análise , Aleitamento Materno/estatística & dados numéricos , Pulmão/fisiopatologia , Adolescente , Poluição do Ar/efeitos adversos , Estudos de Casos e Controles , Criança , China , Estudos Transversais , Exposição Ambiental , Feminino , Humanos , Masculino , Material Particulado/efeitos adversos , Material Particulado/análise , Testes de Função Respiratória/estatística & dados numéricos
7.
JAMA Netw Open ; 2(3): e190318, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30848806

RESUMO

Importance: Which cardiometabolic risk factors (eg, hypertension, type 2 diabetes, overweight or obesity, and dyslipidemia) are more sensitive to long-term exposure to ambient air pollution and whether participants with these conditions are more susceptible to the cardiovascular effects of air pollution remain unclear. Objectives: To evaluate the associations among long-term exposure to air pollutants, cardiometabolic risk factors, and cardiovascular disease (CVD) prevalence. Design, Setting, and Participants: This population-based cross-sectional study was conducted from April 1 through December 31, 2009, in 3 cities in Northeastern China. Participants were adults aged 18 to 74 years who had lived in study area for 5 years or longer. Data analysis was performed from May 1 through December 31, 2018. Exposures: Long-term (2006-2008) exposure to air pollutants was measured using a spatiotemporal statistical model (particulate matter with an aerodynamic diameter of ≤2.5 µm [PM2.5] and ≤1.0 µm [PM1.0]) and data from air monitoring stations (particulate matter with an aerodynamic diameter of ≤10.0 µm [PM10.0], sulfur dioxide [SO2], nitrogen dioxide [NO2], and ozone [O3]). Main Outcomes and Measures: Cardiovascular disease was determined by self-report of physician-diagnosed CVD. Blood pressure, body mass index, and levels of triglycerides and low-density lipoprotein cholesterol were measured using standard methods. Results: Participants included 15 477 adults (47.3% women) with a mean (SD) age of 45.0 (13.5) years. The prevalence of CVD was 4.8%, and the prevalence of cardiometabolic risk factors ranged from 8.6% (hyperbetalipoproteinemia) to 40.5% (overweight or obesity). Mean (SD) air pollutant concentrations ranged from 35.3 (5.5) µg/m3 (for NO2) to 123.1 (14.6) µg/m3 (for PM10.0). Associations with air pollutants were identified for individuals with hyperbetalipoproteinemia (eg, odds ratio [OR], 1.36 [95% CI, 1.03-1.78] for a 10-µg/m3 increase in PM1.0) and the weakest association for those with for overweight or obesity (eg, OR, 1.06 [95% CI, 1.02-1.09] for a 10-µg/m3 increase in PM1.0). Cardiometabolic risk factors only partially mediated associations between air pollution and CVD. However, they modified the associations such that greater associations were found in participants with these cardiometabolic conditions (eg, ORs for CVD and per 10-µg/m3 increase in PM1.0, 1.22 [95% CI, 1.12-1.33] in participants with hyperbetalipoproteinemia and 1.07 [95% CI, 0.98-1.16] in participants without hyperbetalipoproteinemia). Conclusions and Relevance: In this population-based study of Chinese adults with CVD, long-term exposure to air pollution was associated with a higher prevalence of cardiometabolic risk factors, and the strongest associations were observed for hyperbetalipoproteinemia. In addition, participants with cardiometabolic risk factors may have been more vulnerable to the effects of air pollution on CVD.


Assuntos
Doenças Cardiovasculares , Hiperlipoproteinemia Tipo II , Exposição por Inalação , Material Particulado , Adulto , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Doenças Cardiovasculares/classificação , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , China/epidemiologia , Correlação de Dados , Estudos Transversais , Feminino , Humanos , Hiperlipoproteinemia Tipo II/diagnóstico , Hiperlipoproteinemia Tipo II/epidemiologia , Exposição por Inalação/efeitos adversos , Exposição por Inalação/análise , Exposição por Inalação/prevenção & controle , Masculino , Pessoa de Meia-Idade , Material Particulado/efeitos adversos , Material Particulado/análise , Prevalência , Fatores de Risco , Tempo
8.
Sci Total Environ ; 652: 1-18, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30347308

RESUMO

Industrial processes, coal combustion, biomass burning (BB), and vehicular transport are important sources of atmospheric fine particles (PM2.5) and contribute to ambient air concentrations of health-hazardous species, such as heavy metals, polycyclic aromatic hydrocarbons (PAH), and oxygenated-PAHs (OPAH). In China, emission controls have been implemented to improve air quality during large events, like the Youth Olympic Games (YOG) in August 2014 in Nanjing. In this work, six measurement campaigns between January 2014 and August 2015 were undertaken in Nanjing to determine the effects of emission controls and meteorological factors on PM2.5 concentration and composition. PAHs, OPAHs, hopanes, n­alkanes, heavy metals, and several other inorganic elements were measured. PM2.5 and potassium concentrations were the highest in May-June 2014 indicating the prevalence of BB plumes in Nanjing. Emission controls substantially reduced concentrations of PM2.5 (31%), total PAHs (59%), OPAHs (37%), and most heavy metals (44-89%) during the YOG compared to August 2015. In addition, regional atmospheric transport and meteorological parameters partly explained the observed differences between the campaigns. The most abundant PAHs and OPAHs were benzo[b,k]fluoranthenes, fluoranthene, pyrene, chrysene, 1,8­naphthalic anhydride, and 9,10­anthracenedione in all campaigns. Carbon preference index and the contribution of wax n­alkanes indicated mainly biogenic sources of n­alkanes in May-June 2014 and anthropogenic sources in the other campaigns. Hopane indexes pointed to vehicular transport as the major source of hopanes, but contribution of coal combustion was detected in winter 2015. The results provide evidence to the local government of the impacts of the air protection regulations. However, differences between individual components were observed, e.g., concentrations of potentially more harmful OPAHs decreased less than concentrations of PAHs. The results suggest that the proportions of hazardous components in the PM2.5 may also change considerably due to emission control measures.

9.
Environ Int ; 120: 516-524, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30153645

RESUMO

BACKGROUND AND OBJECTIVES: Little is known about PM1 effects on respiratory health, relative to larger size fractions (PM2.5). To address this literature gap, we assessed associations between PM1 exposure and asthmatic symptoms in Chinese children and adolescents, compared with PM2.5. METHODS: A total of 59,754 children, aged 2-17 years, were recruited from 94 kindergartens, elementary and middle schools in the Seven Northeast Cities (SNEC) study, during 2012-2013. We obtained information on asthma and asthma-related symptoms including wheeze, persistent phlegm, and persistent cough using a standardized questionnaire developed by the American Thoracic Society. PM1 and PM2.5 concentrations were estimated using a spatial statistical model matched to the children's geocoded home addresses. To examine the associations, mixed models with school/kindergarten as random intercept were used, controlling for covariates. RESULTS: Odds ratios (ORs) of doctor-diagnosed asthma associated with a 10-µg/m3 increase for PM1 and PM2.5 were 1.56 (95% CI: 1.46-1.66) and 1.50 (1.41-1.59), respectively, and similar pattern were observed for other outcomes. Interaction analyses indicated that boys and the individuals with an allergic predisposition may be vulnerable subgroups. For example, among children with allergic predisposition, the ORs for doctor diagnosed asthma per 10 µg/m3 increase in PM1 was 1.71 (95% CI: 1.60-1.83), which was stronger than in their counterparts (1.46; 1.37-1.56) (pfor interaction < 0.05). CONCLUSIONS: This study indicated that long-term exposure to PM1 may increase the risk of asthma and asthma-related symptoms, especially among boys and those with allergic predisposition. Furthermore, these positive associations for PM1 were very similar to those for PM2.5.


Assuntos
Poluentes Atmosféricos/análise , Asma/epidemiologia , Tosse/epidemiologia , Hipersensibilidade/epidemiologia , Material Particulado/análise , Adolescente , Criança , Pré-Escolar , China/epidemiologia , Cidades/epidemiologia , Monitoramento Ambiental , Feminino , Humanos , Masculino , Razão de Chances , Tamanho da Partícula , Sons Respiratórios
10.
Sci Total Environ ; 639: 1290-1310, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29929296

RESUMO

Ambient inhalable particulate matter (PM) is a serious health concern worldwide, but especially so in China where high PM concentrations affect huge populations. Atmospheric processes and emission sources cause spatial and temporal variations in PM concentration and chemical composition, but their influence on the toxicological characteristics of PM are still inadequately understood. In this study, we report an extensive chemical and toxicological characterization of size-segregated urban air inhalable PM collected in August and October 2013 from Nanjing, and assess the effects of atmospheric processes and likely emission sources. A549 human alveolar epithelial cells were exposed to day- and nighttime PM samples (25, 75, 150, 200, 300 µg/ml) followed by analyses of cytotoxicity, genotoxicity, cell cycle, and inflammatory response. PM10-2.5 and PM0.2 caused the greatest toxicological responses for different endpoints, illustrating that particles with differing size and chemical composition activate distinct toxicological pathways in A549 cells. PM10-2.5 displayed the greatest oxidative stress and genotoxic responses; both were higher for the August samples compared with October. In contrast, PM0.2 and PM2.5-1.0 samples displayed high cytotoxicity and substantially disrupted cell cycle; August samples were more cytotoxic whereas October samples displayed higher cell cycle disruption. Several components associated with combustion, traffic, and industrial emissions displayed strong correlations with these toxicological responses. The lower responses for PM1.0-0.2 compared to PM0.2 and PM2.5-1.0 indicate diminished toxicological effects likely due to aerosol aging and lower proportion of fresh emission particles rich in highly reactive chemical components in the PM1.0-0.2 fraction. Different emission sources and atmospheric processes caused variations in the chemical composition and toxicological responses between PM fractions, sampling campaigns, and day and night. The results indicate different toxicological pathways for coarse-mode particles compared to the smaller particle fractions with typically higher content of combustion-derived components. The variable responses inside PM fractions demonstrate that differences in chemical composition influence the induced toxicological responses.

11.
Lancet Planet Health ; 2(2): e64-e73, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29615239

RESUMO

BACKGROUND: Health effects of air pollution on diabetes have been scarcely studied in developing countries. We aimed to explore the associations of long-term exposure to ambient particulate matter (PM) and gaseous pollutants with diabetes prevalence and glucose-homoeostasis markers in China. METHODS: Between April 1 and Dec 31, 2009, we recruited a total of 15 477 participants aged 18-74 years using a random number generator and a four-staged, stratified and cluster sampling strategy from a large cross-sectional study (the 33 Communities Chinese Health Study) from three cities in Liaoning province, northeastern China. Fasting and 2 h insulin and glucose concentrations and the homoeostasis model assessment of insulin resistance index and ß-cell function were used as glucose-homoeostasis markers. Diabetes was defined according to the American Diabetes Association's recommendations. We calculated exposure to air pollutants using data from monitoring stations (PM with an aerodynamic diameter of 10 µm or less [PM10], sulphur dioxide, nitrogen dioxide, and ozone) and a spatial statistical model (PM with an aerodynamic diameter of 1 µm or less [PM1] and 2·5 µm or less [PM2·5]). We used two-level logistic regression and linear regression analyses to assess associations between exposure and outcomes, controlling for confounders. FINDINGS: All the studied pollutants were significantly associated with increased diabetes prevalence (eg, the adjusted odds ratios associated with an increase in IQR for PM1, PM2·5, and PM10 were 1·13, 95% CI 1·04-1·22; 1·14, 1·03-1·25; and 1·20, 1·12-1·28, respectively). These air pollutants were also associated with higher concentrations of fasting glucose (0·04-0·09 mmol/L), 2 h glucose (0·10-0·19 mmol/L), and 2 h insulin (0·70-2·74 µU/L). No association was observed for the remaining biomarkers. Stratified analyses indicated greater effects on the individuals who were younger (<50 years) or overweight or obese. INTERPRETATION: Long-term exposure to air pollution was associated with increased risk of diabetes in a Chinese population, particularly in individuals who were younger or overweight or obese. FUNDING: The National Key Research and Development Program of China, the National Natural Science Foundation of China, the Fundamental Research Funds for the Central Universities, the Guangdong Province Natural Science Foundation, the Career Development Fellowship of Australian National Health and Medical Research Council, and the Early Career Fellowship of Australian National Health and Medical Research Council.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Diabetes Mellitus Tipo 2/epidemiologia , Exposição Ambiental/efeitos adversos , Material Particulado/efeitos adversos , Adulto , Idoso , Poluição do Ar/efeitos adversos , Biomarcadores/metabolismo , China/epidemiologia , Estudos Transversais , Diabetes Mellitus Tipo 2/induzido quimicamente , Feminino , Glucose/metabolismo , Homeostase , Humanos , Masculino , Pessoa de Meia-Idade , Dióxido de Nitrogênio/efeitos adversos , Razão de Chances , Ozônio/efeitos adversos , Prevalência , Análise de Regressão , Dióxido de Enxofre/efeitos adversos , Adulto Jovem
12.
Environ Sci Technol ; 52(8): 4979-4988, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29517225

RESUMO

Residential wood combustion (RWC) emits high amounts of volatile organic compounds (VOCs) into ambient air, leading to formation of secondary organic aerosol (SOA), and various health and climate effects. In this study, the emission factors of VOCs from a logwood-fired modern masonry heater were measured using a Proton-Transfer-Reactor Time-of-Flight Mass Spectrometer. Next, the VOCs were aged in a 29 m3 Teflon chamber equipped with UV black lights, where dark and photochemical atmospheric conditions were simulated. The main constituents of the VOC emissions were carbonyls and aromatic compounds, which accounted for 50%-52% and 30%-46% of the detected VOC emission, respectively. Emissions were highly susceptible to different combustion conditions, which caused a 2.4-fold variation in emission factors. The overall VOC concentrations declined considerably during both dark and photochemical aging, with simultaneous increase in particulate organic aerosol mass. Especially furanoic and phenolic compounds decreased, and they are suggested to be the major precursors of RWC-originated SOA in all aging conditions. On the other hand, dark aging produced relatively high amounts of nitrogen-containing organic compounds in both gas and particulate phase, while photochemical aging increased especially the concentrations of certain gaseous carbonyls, particularly acid anhydrides.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Aerossóis , Gases , Smog
13.
Environ Sci Technol ; 51(3): 1423-1432, 2017 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28009165

RESUMO

Interactions between anthropogenic and biogenic emissions, and implications for aerosol production, have raised particular scientific interest. Despite active research in this area, real anthropogenic emission sources have not been exploited for anthropogenic-biogenic interaction studies until now. This work examines these interactions using α-pinene and pellet boiler emissions as a model test system. The impact of pellet boiler emissions on secondary organic aerosol (SOA) formation from α-pinene photo-oxidation was studied under atmospherically relevant conditions in an environmental chamber. The aim of this study was to identify which of the major pellet exhaust components (including high nitrogen oxide (NOx), primary particles, or a combination of the two) affected SOA formation from α-pinene. Results demonstrated that high NOx concentrations emitted by the pellet boiler reduced SOA yields from α-pinene, whereas the chemical properties of the primary particles emitted by the pellet boiler had no effect on observed SOA yields. The maximum SOA yield of α-pinene in the presence of pellet boiler exhaust (under high-NOx conditions) was 18.7% and in the absence of pellet boiler exhaust (under low-NOx conditions) was 34.1%. The reduced SOA yield under high-NOx conditions was caused by changes in gas-phase chemistry that led to the formation of organonitrate compounds.


Assuntos
Aerossóis/química , Poluentes Atmosféricos/química , Monoterpenos/química , Oxirredução , Emissões de Veículos
14.
Part Fibre Toxicol ; 11: 60, 2014 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-25420696

RESUMO

BACKGROUND: Ambient air particulate matter (PM) is increasingly considered to be a causal factor evoking severe adverse health effects. People spend the majority of their time indoors, which should be taken into account especially in future risk assessments, when the role of outdoor air particles transported into indoor air is considered. Therefore, there is an urgent need for characterization of possible sources seasonally for harmful health outcomes both indoors and outdoors. METHODS: In this study, we collected size-segregated (PM(10-2.5), PM(2.5-0.2)) particulate samples with a high volume cascade impactor (HVCI) simultaneously both indoors and outdoors of a new single family detached house at four different seasons. The chemical composition of the samples was analyzed as was the presence of microbes. Mouse macrophages were exposed to PM samples for 24 hours. Thereafter, the levels of the proinflammatory cytokines, NO-production, cytotoxicity and changes in the cell cycle were investigated. The putative sources of the most toxic groups of constituents were resolved by using the principal component analysis (PCA) and pairwise dependencies of the variables were detected with Spearman correlation. RESULTS: Source-related toxicological responses clearly varied according to season. The role of outdoor sources in indoor air quality was significant only in the warm seasons and the significance of outdoor microbes was also larger in the indoor air. During wintertime, the role of indoor sources of the particles was more significant, as was also the case for microbes. With respect to the outdoor sources, soil-derived particles during a road dust episode and local wood combustion in wintertime were the most important factors inducing toxicological responses. CONCLUSIONS: Even though there were clear seasonal differences in the abilities of indoor and outdoor air to induce inflammatory and cytotoxic responses, there were relatively small differences in the chemical composition of the particles responsible of those effects. Outdoor sources have only a limited effect on indoor air quality in a newly built house with a modern ventilation system at least in a low air pollution environment. The most important sources for adverse health related toxicological effects were related to soil-derived constituents, local combustion emissions and microbes.


Assuntos
Microbiologia do Ar , Poluição do Ar em Ambientes Fechados/efeitos adversos , Macrófagos/efeitos dos fármacos , Material Particulado/toxicidade , Animais , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Transformada , Sobrevivência Celular , Citocinas/metabolismo , Poeira/análise , Finlândia , Bactérias Gram-Positivas/crescimento & desenvolvimento , Bactérias Gram-Positivas/imunologia , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Macrófagos/citologia , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Fungos Mitospóricos/crescimento & desenvolvimento , Fungos Mitospóricos/imunologia , Fungos Mitospóricos/isolamento & purificação , Óxido Nítrico/metabolismo , Tamanho da Partícula , Material Particulado/química , Análise de Componente Principal , Características de Residência , Estações do Ano , Fumaça/efeitos adversos , Fumaça/análise , Microbiologia do Solo
15.
Toxicol In Vitro ; 27(5): 1550-61, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23583641

RESUMO

Ambient air particulate matter (PM) as well as microbial contaminants in the indoor air are known to cause severe adverse health effects. It has been shown that there is a clear seasonal variation in the potency of outdoor air particles to evoke inflammation and cytotoxicity. However, the role of outdoor sources in the indoor air quality, especially on its toxicological properties, remains largely unknown. In this study, we collected size segregated (PM10-2.5, PM2.5-0.2 and PM0.2) particulate samples with a high volume cascade impactor (HVCI) on polyurethane foam and fluoropore membrane filters. The samples were collected during four different seasons simultaneously from indoor and outdoor air. Thereafter, the samples were weighed and extracted with methanol from the filters before undergoing toxicological analyses. Mouse macrophages (RAW264.7) were exposed to particulate sample doses of 50, 150 and 300µg/ml for 24h. Thereafter, the levels of the proinflammatory cytokine (TNF-α), NO-production, cytotoxicity (MTT-test) and changes in the cell cycle (SubG1, G1, S and G2/M phases) were investigated. PM10-2.5 particles evoked the highest inflammatory and cytotoxic responses. Instead, PM2.5-0.2 samples exerted the greatest effect on apoptotic activity in the macrophages. With respect to the outdoor air samples, particles collected during warm seasons had a stronger potency to induce inflammatory and cytotoxic responses, whereas no such clear effect was seen with the corresponding indoor air samples. Outdoor air samples were associated with higher inflammatory potential, whereas indoor air samples had overall higher cytotoxic properties. This indicates that the outdoor air has a limited influence on the indoor air quality in a modern house. Thus, the indoor sources dominate the toxicological responses obtained from samples collected inside house.


Assuntos
Poluição do Ar em Ambientes Fechados/efeitos adversos , Material Particulado/toxicidade , Animais , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Permeabilidade da Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Habitação , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Óxido Nítrico/metabolismo , Tamanho da Partícula , Material Particulado/química , Estações do Ano
16.
Environ Sci Technol ; 47(6): 2645-53, 2013 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-23419193

RESUMO

This study presents results of direct observations of aerosol chemical composition in clouds. A high-resolution time-of-flight aerosol mass spectrometer was used to make measurements of cloud interstitial particles (INT) and mixed cloud interstitial and droplet residual particles (TOT). The differences between these two are the cloud droplet residuals (RES). Positive matrix factorization analysis of high-resolution mass spectral data sets and theoretical calculations were performed to yield distributions of chemical composition of the INT and RES particles. We observed that less oxidized hydrocarbon-like organic aerosols (HOA) were mainly distributed into the INT particles, whereas more oxidized low-volatile oxygenated OA (LVOOA) mainly in the RES particles. Nitrates existed as organic nitrate and in chemical form of NH(4)NO(3). Organic nitrates accounted for 45% of total nitrates in the INT particles, in clear contrast to 26% in the RES particles. Meanwhile, sulfates coexist in forms of acidic NH(4)HSO(4) and neutralized (NH(4))(2)SO(4). Acidic sulfate made up 64.8% of total sulfates in the INT particles, much higher than 10.7% in the RES particles. The results indicate a possible joint effect of activation ability of aerosol particles, cloud processing, and particle size effects on cloud formation.


Assuntos
Aerossóis/química , Atmosfera , Espectrometria de Massas/métodos , Ácidos/análise , Nitratos/análise , Tamanho da Partícula , Sulfatos/análise
17.
J Occup Environ Hyg ; 5(1): 28-35, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18041642

RESUMO

The performance of four sampling devices for inhalable dust and three devices for respirable dust was tested with different kinds of dusts in the laboratory and in the field. The IOM sampler was chosen as the reference method for inhalable dust, and the IOM sampler provided with the porous plastic foam media was used as the reference method for respirable dust. The other tested instruments were the Button sampler, the optical Grimm aerosol monitor, and the Dekati two-stage cascade impactor with cutoff sizes of 10 and 4 mu m. The study confirmed the applicability of the IOM and Button samplers. The new foam product followed the respirable criteria well. However, the foam sampler was unstable for measuring inhalable dust, probably due to its moisture absorption. In addition, high dust loads should be avoided with the foam sampler due to increase in filtering efficiency. The concentrations of inhalable dust measured with the Button sampler, the Grimm monitor, and the impactor sampler were usually close to those measured with the reference sampler. On the other hand, impactor sampling yielded higher respirable dust concentrations than the reference method in the field, which may have been caused by particle bounce; high dust loads should be avoided while using the impactor. The results also showed that the Grimm monitor enables real-time dust concentration determinations that are accurate enough for routine monitoring of occupational exposure and for testing efficiency of control measures in workplaces.


Assuntos
Poluentes Ocupacionais do Ar/análise , Poeira/análise , Monitoramento Ambiental/instrumentação , Exposição por Inalação/análise , Laboratórios , Metais/análise , Minerais/análise , Exposição Ocupacional/análise , Solo/análise
18.
Environ Sci Technol ; 38(9): 2707-14, 2004 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15180069

RESUMO

Diesel exhaust particles are the major constituent of urban carbonaceous aerosol being linked to a large range of adverse environmental and health effects. In this work, the effects of fuel reformulation, oxidation catalyst, engine type, and engine operation parameters on diesel particle emission characteristics were investigated. Particle emissions from an indirect injection (IDI) and a direct injection (DI) engine car operating under steady-state conditions with a reformulated low-sulfur, low-aromatic fuel and a standard-grade fuel were analyzed. Organic (OC) and elemental (EC) carbon fractions of the particles were quantified by a thermal-optical transmission analysis method and particle size distributions measured with a scanning mobility particle sizer (SMPS). The particle volatility characteristics were studied with a configuration that consisted of a thermal desorption unit and an SMPS. In addition, the volatility of size-selected particles was determined with a tandem differential mobility analyzer technique. The reformulated fuel was found to produce 10-40% less particulate carbon mass compared to the standard fuel. On the basis of the carbon analysis, the organic carbon contributed 27-61% to the carbon mass of the IDI engine particle emissions, depending on the fuel and engine operation parameters. The fuel reformulation reduced the particulate organic carbon emissions by 10-55%. In the particles of the DI engine, the organic carbon contributed 14-26% to the total carbon emissions, the advanced engine technology, and the oxidation catalyst, thus reducing the OC/EC ratio of particles considerably. A relatively good consistency between the particulate organic fraction quantified with the thermal optical method and the volatile fraction measured with the thermal desorption unit and SMPS was found.


Assuntos
Gasolina , Emissões de Veículos , Aerossóis , Engenharia , Monitoramento Ambiental/métodos , Óptica e Fotônica , Tamanho da Partícula , Reprodutibilidade dos Testes , Temperatura Ambiente , Volatilização
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