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1.
Neurochem Int ; 136: 104715, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32169588

RESUMO

Every second we inhale a danger in the air; many particles in the atmosphere can influence our lives. Outdoor air pollution, especially particulate matter is the largest environmental risk factor and has been associated with many cardiovascular and lung diseases. Importantly, air pollution has recently been discovered to also impact the brain. Here, we review the effects of air pollution on glial cells of the brain, astrocytes and microglia, and the tightly controlled interplay between these cell types. We focus on how traffic related air pollutants which include both gaseous and particulate emissions and their secondary products influence the intercellular communication of microglia and astrocytes. Finally, we place these air pollution and glial interactions in a larger context by discussing their impact on neurodegeneration.

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 ; 709: 135802, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-31887498

RESUMO

Although carbon black (CB) particles have potential hazards to human health, the toxicological studies on CB are still limited. The purpose of this study was to investigate the effect of oxidative stress induced by ultrafine CB particles on apoptosis in vivo and vitro. Male C57BL/6 mice were inhalation exposed to CB for 28 days, and 16HBE cells were treated by CB particles and also added antioxidant (NAC). Antioxidant enzymes activities (CAT, SOD, GSH-Px) and ROS in the lungs and cells were evaluated. Apoptosis-related proteins (Bcl-2, Bax, Cleaved Caspase-3, pro-Caspase-3, Caspase-7, Caspase-8, Caspase-9, PARP-1) were tested by Western blot (WB), immunohistochemistry (IHC), and real-time PCR. The reduction of antioxidant enzymes activities and the addition of ROS in CB exposure groups were observed, and the gene and apoptosis-related proteins levels were increased in CB exposure mice. The results of CB-treated 16HBE cells were consistent with those of mice, and apoptosis rate was increased in CB-treated 16HBE cells. When the cells were treated with NAC, ROS induced by CB decreased, SOD and CAT activities of CB-treated 16HBE cells were increased. Apoptosis rate of 16HBE cells treated with NAC and CB was significantly decreased, and the expression of C-Caspase-3 was also decreased. Therefore, oxidative stress induced by ultrafine CB particles can elicit apoptosis in vivo and vitro. Antioxidants can significantly reduce oxidative damage and apoptosis induced by CB.

6.
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
7.
Indoor Air ; 2019 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-31883508

RESUMO

In vitro models mimicking the human respiratory system are essential when investigating the toxicological effects of inhaled indoor air particulate matter (PM). We present a pulmonary cell culture model for studying indoor air PM toxicity. We exposed normal human bronchial epithelial cells, grown on semi-permeable cell culture membranes, to four doses of indoor air PM in the air-liquid interface. We analyzed the chemokine interleukin-8 concentration from the cell culture medium, protein concentration from the apical wash, measured tissue electrical resistance, and imaged airway constructs using light and transmission electron microscopy. We sequenced RNA using a targeted RNA toxicology panel for 386 genes associated with toxicological responses. PM was collected from a non-complaint residential environment over 1 week. Sample collection was concomitant with monitoring size-segregated PM counts and determination of microbial levels and diversity. PM exposure was not acutely toxic for the cells, and we observed up-regulation of 34 genes and down-regulation of 17 genes when compared to blank sampler control exposure. The five most up-regulated genes were related to immunotoxicity. Despite indications of incomplete cell differentiation, this model enabled the comparison of a toxicological transcriptome associated with indoor air PM exposure.

8.
JAMA Netw Open ; 2(12): e1917862, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31851349

RESUMO

Importance: Few studies have investigated the association between greenness and childhood attention-deficit/hyperactivity disorder (ADHD). Objective: To evaluate the association between greenness surrounding schools or kindergartens and symptoms of ADHD in children. Design, Setting, and Participants: This population-based cross-sectional study was performed between April 2012 and January 2013 in 7 cities in northeastern China. This analysis included 59 754 children (aged 2-17 years) from 94 schools and kindergartens, who had resided in the study area for 2 years or longer. Data were analyzed from April 15, 2019, to October 10, 2019. Exposures: Greenness surrounding each child's school or kindergarten was estimated using 2 satellite image-derived vegetation indexes: the normalized difference vegetation index and the soil-adjusted vegetation index. Main Outcomes and Measures: Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) scales were used to measure ADHD symptoms (9 inattention symptoms and 9 hyperactivity-impulsivity symptoms). Parents or guardians rated the frequency of each of 18 ADHD symptoms during the preceding 6 months. Children with 6 or more symptoms of either inattention or hyperactivity-impulsivity were defined as having ADHD symptoms. Generalized linear mixed models were applied to estimate the association between greenness and ADHD symptoms. Results: The mean (SD) age of the 59 754 study participants was 10.3 (3.6) years, and 29 494 (49.4%) were girls. A total of 2566 participants (4.3%) had ADHD symptoms. Greenness levels differed substantially across schools and kindergartens. The normalized difference vegetation index within 500 m of a school or kindergarten ranged from -0.09 to 0.77. Greater greenness levels were associated with lower odds of ADHD symptoms. In covariate-adjusted models, a 0.1-unit increase in normalized difference vegetation index or soil-adjusted vegetation index within 500 m of a school or kindergarten was significantly associated with lower odds of ADHD symptoms (odds ratios, 0.87 [95% CI, 0.83-0.91] and 0.80 [95% CI, 0.74-0.86], respectively; P < .001 for both). The associations were robust in a series of sensitivity analyses. Conclusions and Relevance: These findings suggest that there may be a beneficial association between school-based greenness and ADHD symptoms in Chinese children. Future longitudinal and mechanistic studies are needed to confirm the findings of this cross-sectional analysis and further explore potential mechanisms of this association.

10.
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
11.
Environ Pollut ; 250: 14-22, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30981931

RESUMO

While exposure to places with higher greenness shows health benefits, evidence is scarce on its lipidemic effects. We assessed the associations between residential greenness and blood lipids and effect mediations by air pollution, physical activity, and adiposity in China. Our study included 15,477 adults from the population-based 33 Communities Chinese Health Study, conducted between April and December 2009, in Northeastern China. We measured total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C). Residential greenness was estimated using two satellite-derived vegetation indices - the Normalized Difference Vegetation Index (NDVI) and the Soil Adjusted Vegetation Index (SAVI). We used both nitrogen dioxide (NO2) and particles ≤2.5 µm in aerodynamic diameter (PM2.5) as proxies of outdoor air pollution. Associations were assessed using linear mixed effects regression models and logistic mixed effects regression models, and mediation analyses were also performed. Living in higher greenness areas was consistently associated with lower TC, TG, and LDL-C levels and higher HDL-C levels (e.g., change in TC, TG, LDL-C, and HDL-C per 0.1-unit increase in NDVI500-m was -1.52%, -3.05%, -1.91%, and 0.52%, respectively). Similar results were obtained for the corresponding dyslipidemias. These associations were generally stronger in women and older adults. While educational levels showed effect modifications, the effect pattern was inconsistent. Both outdoor air pollution and body mass index mediated 9.1-62.3% and 5.6-40.1% of the associations for greenness and blood lipids, respectively, however, physical activity did not. Our results suggest beneficial associations between residing in places with higher greenness and blood lipid levels, especially in women and the elder individuals. The associations were partly mediated by lower air pollution and adiposity.


Assuntos
Poluição do Ar/análise , Ambiente Construído , Exposição Ambiental/análise , Lipídeos/sangue , População Urbana , Adiposidade , Idoso , Poluição do Ar/efeitos adversos , Índice de Massa Corporal , China , Exposição Ambiental/efeitos adversos , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Dióxido de Nitrogênio/efeitos adversos , Dióxido de Nitrogênio/análise , Obesidade/epidemiologia , Material Particulado/efeitos adversos , Material Particulado/análise
12.
Environ Int ; 126: 727-734, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30878868

RESUMO

BACKGROUND: Living in greener areas has many health benefits, but evidence concerning the effects on blood pressure remains mixed. We sought to assess associations between community greenness and both blood pressure and hypertension in Chinese urban dwellers, and whether the associations were mediated by air pollution, body mass index, and physical activity. METHODS: We analyzed data from 24,845 adults participating in the 33 Communities Chinese Health Study, which was conducted in Northeastern China during 2009. We measured each participant's blood pressure according to a standardized protocol. We assessed community greenness using two satellite-derived vegetation indexes - the Normalized Difference Vegetation Index (NDVI) and the Soil Adjusted Vegetation Index (SAVI). Particulate matter ≤2.5 µm and nitrogen dioxide were used as proxies of ambient air pollution. We applied generalized linear mixed models to investigate the association between greenness and blood pressure. We also performed mediation analyses. RESULTS: Living in greener areas was associated with lower blood pressure and hypertension prevalence; an interquartile range increase in both NDVI500-m and SAVI500-m were significantly associated with reductions in systolic blood pressure of 0.82 mm Hg (95% CI: -1.13, -0.51) and 0.89 mm Hg (95% CI: -1.21, -0.57), respectively. The same increases in greenness were also significantly associated with a 5% (95% CI: 1%, 8%) and 5% (95% CI: 1%, 9%) lower odds of having hypertension, respectively. These associations remained consistent in sensitivity analyses. The associations were stronger among women than men. Air pollutants and body mass index partly mediated the associations, but there was no evidence of mediation effects for physical activity. CONCLUSIONS: Our findings indicate beneficial associations between community greenness and blood pressure in Chinese adults, especially for women. Air pollution and body mass index only partly mediated the associations.


Assuntos
Adiposidade , Poluição do Ar/análise , Pressão Sanguínea , Meio Ambiente , Exercício , Hipertensão/epidemiologia , Adulto , Idoso , China/epidemiologia , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
13.
Environ Pollut ; 248: 888-897, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30856504

RESUMO

There is currently great interest in replacing fossil-oil with renewable fuels in energy production. Fast pyrolysis bio-oil (FPBO) made of lignocellulosic biomass is one such alternative to replace fossil oil, such as heavy fuel oil (HFO), in energy boilers. However, it is not known how this fuel change will alter the quantity and quality of emissions affecting human health. In this work, particulate emissions from a real-scale commercially operated FPBO boiler plant are characterized, including extensive physico-chemical and toxicological analyses. These are then compared to emission characteristics of heavy fuel-oil and wood fired boilers. Finally, the effects of the fuel choice on the emissions, their potential health effects and the requirements for flue gas cleaning in small-to medium-sized boiler units are discussed. The total suspended particulate matter and fine particulate matter (PM1) concentrations in FPBO boiler flue gases before filtration were higher than in HFO boilers and lower or on a level similar to wood-fired grate boilers. FPBO particles consisted mainly of ash species and contained less polycyclic aromatic hydrocarbons (PAH) and heavy metals than had previously been measured from HFO combustion. This feature was clearly reflected in the toxicological properties of FPBO particle emissions, which showed less acute toxicity effects on the cell line than HFO combustion particles. The electrostatic precipitator used in the boiler plant efficiently removed flue gas particles of all sizes. Only minor differences in the toxicological properties of particles upstream and downstream of the electrostatic precipitator were observed, when the same particulate mass from both situations was given to the cells.


Assuntos
Poluentes Atmosféricos/análise , Calefação/métodos , Material Particulado/análise , Óleos Vegetais/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Polifenóis/química , Pirólise , Finlândia , Combustíveis Fósseis/análise , Óleos Combustíveis/análise , Madeira/química
14.
Sci Total Environ ; 663: 60-67, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30708217

RESUMO

BACKGROUND: Perfluoroalkyl substances (PFASs) are synthetic chemicals widely used in industry and for commercial products. Their immunomodulatory effects are a growing health concern in children. Hand, Foot and Mouth Disease (HFMD) is a common childhood viral infection, and increased incidence of which has parallel the rise in PFAS exposure in the Asia-Pacific region. OBJECTIVE: We conducted the first study to assess whether prenatal exposure to PFAS was associated with a reduction in HFMD virus antibodies in infants. METHODS: We enrolled 201 mother-infant pairs from the Guangzhou Birth Cohort Study from July to October 2013. High performance liquid chromatography-mass spectrometry was employed to determine concentrations of specific PFAS isomers in cord blood. Neutralizing antibodies titers were measured against two HFMD viruses, enterovirus 71 (EV71) and coxsackievirus A 16 (CA16), in cord blood serum and blood serum at three months of age. RESULTS: Higher umbilical cord blood PFAS concentrations were associated with lower EV71 and CA16 antibody concentrations. A doubling in the composite sum of cord blood PFASs in three month old infants was associated with significant increase in the risk of HFMD antibody concentration below clinical protection level (≥1:8 titers) for CA16 (odds ratio, OR: 2.74 [95% confidence interval (CI): 1.33, 5.61] and for EV71 (OR = 4.55, 95% CI: 1.45, 4.28). This association was higher in boys at three months of age for CA16. CONCLUSIONS: Our findings suggest that cord blood PFAS exposure is associated with lower HFMD antibody in infancy. Given the widespread nature of PFAS exposures and the high global incidence of HFMD globally, these findings have substantial public health implications and therefore, these associations need to be replicated in a larger study to more definitively address the risk.


Assuntos
Anticorpos Antivirais/imunologia , Fluorcarbonetos/efeitos adversos , Vírus da Febre Aftosa/imunologia , Doença de Mão, Pé e Boca/imunologia , Efeitos Tardios da Exposição Pré-Natal/imunologia , Adulto , Anticorpos Neutralizantes/imunologia , China , Estudos de Coortes , Feminino , Sangue Fetal/química , Humanos , Lactente , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/virologia , Fatores Sexuais , Adulto Jovem
15.
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.

16.
Pediatr Allergy Immunol ; 29(8): 815-822, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30152886

RESUMO

BACKGROUND: Studies conducted in farm environments suggest that diverse microbial exposure promotes children's lung health. The underlying mechanisms are unclear, and the development of asthma-preventive strategies has been delayed. More comprehensive investigation of the environment-induced immunoregulation is required for better understanding of asthma pathogenesis and prevention. Exposure to air pollution, including particulate matter (PM), is a risk factor for asthma, thus providing an excellent counterpoint for the farm-effect research. Lack of comparable data, however, complicates interpretation of the existing information. We aimed to explore the immunoregulatory effects of cattle farm dust (protective, Finland) and urban air PM (high-risk, China) for the first time using identical research methods. METHODS: We stimulated PBMCs of 4-year-old children (N = 18) with farm dust and size-segregated PM and assessed the expression of immune receptors CD80 and ILT4 on dendritic cells and monocytes as well as cytokine production of PBMCs. Environmental samples were analysed for their composition. RESULTS: Farm dust increased the percentage of cells expressing CD80 and the cytokine production of children's immune cells, whereas PM inhibited the expression of important receptors and the production of soluble mediators. Although PM samples induced parallel immune reactions, the size-fraction determined the strength of the effects. CONCLUSIONS: Our study demonstrates the significance of using the same research framework when disentangling shared and distinctive immune pathways operating in different environments. Observed stimulatory effects of farm dust and inhibitory effects of PM could shape responses towards respiratory pathogens and allergens, and partly explain differences in asthma prevalence between studied environments.


Assuntos
Poluentes Atmosféricos/imunologia , Poluição do Ar/efeitos adversos , Antígeno B7-1/metabolismo , Exposição Ambiental/efeitos adversos , Glicoproteínas de Membrana/metabolismo , Receptores Imunológicos/metabolismo , Alérgenos/imunologia , Técnicas de Cultura de Células , Pré-Escolar , Citocinas/metabolismo , Fazendas/estatística & dados numéricos , Feminino , Humanos , Imunofenotipagem , Leucócitos Mononucleares/metabolismo , Masculino , Material Particulado/imunologia , Fatores de Risco
17.
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
18.
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.

19.
PLoS One ; 13(2): e0192453, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29466392

RESUMO

BACKGROUND: In vitro studies with monocultures of human alveolar cells shed deeper knowledge on the cellular mechanisms by which particulate matter (PM) causes toxicity, but cannot account for mitigating or aggravating effects of cell-cell interactions on PM toxicity. METHODS: We assessed inflammation, oxidative stress as well as cytotoxic and genotoxic effects induced by PM from the combustion of different types of wood logs and softwood pellets in three cell culture setups: two monocultures of either human macrophage-like cells or human alveolar epithelial cells, and a co-culture of these two cell lines. The adverse effects of the PM samples were compared between these setups. RESULTS: We detected clear differences in the endpoints between the mono- and co-cultures. Inflammatory responses were more diverse in the macrophage monoculture and the co-culture compared to the epithelial cells where only an increase of IL-8 was detected. The production of reactive oxygen species was the highest in epithelial cells and macrophages seemed to have protective effects against oxidative stress from the PM samples. With no metabolically active cells at the highest doses, the cytotoxic effects of the PM samples from the wood log combustion were far more pronounced in the macrophages and the co-culture than in the epithelial cells. All samples caused DNA damage in macrophages, whereas only beech and spruce log combustion samples caused DNA damage in epithelial cells. The organic content of the samples was mainly associated with cytotoxicity and DNA damage, while the metal content of the samples correlated with the induction of inflammatory responses. CONCLUSIONS: All of the tested PM samples induce adverse effects and the chemical composition of the samples determines which pathway of toxicity is induced. In vitro testing of the toxicity of combustion-derived PM in monocultures of one cell line, however, is inadequate to account for all the possible pathways of toxicity.


Assuntos
Material Particulado/toxicidade , Madeira , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Humanos , Inflamação/induzido quimicamente , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Testes de Mutagenicidade , Estresse Oxidativo/efeitos dos fármacos , Alvéolos Pulmonares/citologia , Alvéolos Pulmonares/efeitos dos fármacos
20.
Toxicol In Vitro ; 44: 164-171, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28711347

RESUMO

Toxicological characterisation of combustion emissions in vitro are often conducted with macrophage cell lines, and the majority of these experiments are based on responses measured at 24h after the exposure. The aim of this study was to investigate how significant role time course plays on toxicological endpoints that are commonly measured in vitro. The RAW264.7 macrophage cell line was exposed to PM1 samples (150µg/ml) from biomass combustion devices representing old and modern combustion technologies for 2, 4, 8, 12, 24 and 32h. After the exposure, cellular metabolic activity, cell membrane integrity, cellular DNA content, DNA damage and production of inflammatory markers were assessed. The present study revealed major differences in the time courses of the responses, statistical differences between the studied samples mostly limiting to differences between modern and old technology samples. Early stage responses consisted of disturbances in metabolic activity and cell membrane integrity. Middle time points revealed increases in chemokine production, whereas late-phase responses exhibited mostly increased DNA-damage, decreased membrane integrity and apoptotic activity. Altogether, these results implicate that the time point of measurement has to be considered carefully, when the toxicity of emission particles is characterised in in vitro study set-ups.


Assuntos
Poluentes Atmosféricos/toxicidade , Material Particulado/toxicidade , Testes de Toxicidade/métodos , Madeira , Animais , Apoptose/efeitos dos fármacos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Quimiocina CXCL2/metabolismo , DNA/metabolismo , Dano ao DNA , Camundongos , Células RAW 264.7 , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo
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