Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.257
Filtrar
1.
Environ Pollut ; 265(Pt B): 115070, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32806460

RESUMO

Particle-bound pollutants can pose a health risk to humans. Inhalation exposure evaluated by total contaminant concentrations significantly overestimates the potential risk. To assess the risk more accurately, bioavailability, which is the fraction that enters into the systemic circulation, should be considered. Researchers have replaced bioavailability by bioaccessibility due to the rapid and cost-efficient measurement for the latter, especially for assessment by oral ingestion. However, contaminants in particulates have different behavior when inhaled than when orally ingested. Some of the contaminants are exhaled along with exhalation, and others are deposited in the lung with the particulates. In addition, a fraction of the contaminants is released into the lung fluid and absorbed by the lung, and another fraction enters systemic circulation under the action of cell phagocytosis on particulates. Even if the release fraction, i.e., release bioaccessibility, is considered, the measurement faces many challenges. The present study highlights the factors influencing release bioaccessibility and the incorporation of inhalation bioaccessibility into the risk assessment of inhaled contaminants. Currently, there are three types of extraction techniques for simulated human lung fluids, including simple chemical solutions, sequential extraction techniques, and physiologically based techniques. The last technique generally uses three kinds of solution: Gamble's solution, Hatch's solution, and artificial lysosomal fluid, which are the most widely used physiologically based simulated human lung fluids. External factors such as simulated lung fluid composition, pH, extraction time, and sorption sinks can affect release bioaccessibility, whereas particle size and contaminant properties are important internal factors. Overall, release bioaccessibility is less used than bioaccessibility considering the deposition fraction when assessing the risk of contaminants in inhaled particulates. The release bioaccessibility measurement poses two main challenges: developing a unified, accurate, stable, simple, and systematic biologically based method, and validating the method through in-vivo assays.


Assuntos
Poeira , Material Particulado , Humanos , Exposição por Inalação/análise , Pulmão , Metais
2.
Environ Pollut ; 266(Pt 2): 115209, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32688075

RESUMO

In everyday life, people are exposed to different concentrations of airborne particles depending on the microenvironment where they perform their different activities. Such exposure can lead to high sub-micron particle doses. The received dose depends on particle concentration to which people are exposed (typically expressed in terms of number or surface area), time spent in each activity or microenvironment (time activity pattern) and amount of air inhaled (inhalation rate). To estimate an actual value of the received dose, all these parameters should be measured under real-life conditions; in fact, the concentrations should be measured on a personal scale (i.e. through a direct exposure assessment), whereas time activity patterns and inhalation rates specific to the activity performed should be considered. The difficulties in obtaining direct measurements of these parameters usually lead to adopt time activity patterns and inhalation rates already available in scientific literature for typical populations, and local outdoor particle concentrations measured with fixed monitoring stations and extrapolated for all the other microenvironments. To overcome these limitations, we propose a full-field method for estimating the received dose of a population sample, in which all the parameters (concentration levels, time activity patterns and inhalation rates) are measured under real-life conditions (also including the inhalation rates, that were evaluated on the basis of the measured heart rates). Specifically, 34 volunteers were continuously monitored for seven days and the data of sub-micron particle concentrations, activities performed, and inhalation rates were recorded. The received dose was calculated with the proposed method and compared with those obtained from different simplified methodologies that consider typical data of particle concentrations, time activity patterns and inhalation rates obtained from literature. The results show that, depending on the methodology used, the differences in the received daily dose can be significant, with a general underestimation of the most simplified method.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Humanos , Exposição por Inalação/análise , Tamanho da Partícula , Material Particulado/análise
3.
Artigo em Inglês | MEDLINE | ID: mdl-32615056

RESUMO

Over the past decades, air pollution has become one of the critical environmental health issues in China. The present study aimed to evaluate links between ambient air pollution and the prevalence of type 2 diabetes mellitus (T2DM) and the levels of glycosylated hemoglobin (HbA1c). A multilevel linear and logistic regression was used to assess these associations among 7,770 participants aged ≥50 years from the WHO Study on global AGEing and adult health (SAGE) in China in 2007-2010. The average exposure to each of pollutants (particulate matter with an aerodynamic diameter of ≤10 µm/≤2.5 µm/≤1 µm [PM10/PM2.5/PM1] and nitrogen dioxide [NO2]) was estimated using a satellite-based spatial statistical model. In logistic models, a 10 µg/m3 increase in PM10 and PM2.5 was associated with increased T2DM prevalence (Prevalence Odds Ratio, POR: 1.27; 95% CI: 1.11, 1.45 and POR: 1.23; 95% CI: 1.03, 1.46). Similar increments in PM10, PM2.5, PM1 and NO2 were associated with increase in HbA1c levels of 1.8% (95% CI: 1.3, 2.3), 1.3% (95% CI: 1.1, 1.5), 0.7% (95% CI: 0.1, 1.3), and 0.8% (95% CI: 0.4, 1.2), respectively. In a large cohort of older Chinese adults, air pollution was liked to both higher T2DM prevalence and elevated HbA1c levels.


Assuntos
Envelhecimento/sangue , Poluentes Atmosféricos/análise , Diabetes Mellitus Tipo 2/epidemiologia , Hemoglobina A Glicada/análise , Exposição por Inalação/análise , Material Particulado/análise , Adulto , Idoso , China/epidemiologia , Estudos Transversais , Diabetes Mellitus Tipo 2/sangue , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Organização Mundial da Saúde
4.
Artigo em Inglês | MEDLINE | ID: mdl-32452753

RESUMO

The large number of vehicles plying in roads is the main cause of traffic jam and air pollution in Hanoi. In this study, the vehicle density and shares of different vehicle types, the traffic flow velocity and roadside air pollutants concentrations were monitored in Chua Boc street, a typical arterial road in the city. The shares of the motorcycle, car and bus fleets in the total on-road traffic in the street were 78.4-87.3, 12.3-20.2 and 0.4-1.4%, respectively. The high density of vehicles caused traffic jam during rush hours and considerably reduced the vehicle speed. The traffic flow velocity during non-rush and rush hours was found to vary from 26.4-34.5 and 10.3-12.1 km/h, respectively. The average concentrations of PM10, PM2.5, SO2, NO2, CO and NMVOC during the rush hours were the following: 117.1 ± 8.5, 65.2 ± 10.6, 113.5 ± 10.9, 138.5 ± 16.0, 6792 ± 998 and 451 ± 71 µg/m3, respectively, which were about 1.9-2.6 times above the levels during non-rush hours. The decrease in vehicle speed during rush hours were strongly correlated with the increase in concentration of PM10 (R2 = 0.732), PM2.5 (R2 = 0.685), SO2 (R2 = 0.578), NO2 (R2 = 0.738), CO (R2 = 0.689) and NMVOC (R2 = 0.747). High levels of these toxic air pollutants in Hanoi city posed a high health risk to humans. Facemask use was more popular among the motorcycle commuters and pedestrians, especially during rush hours, than among the people working for extended time period alongside of the street.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Exposição por Inalação/análise , Material Particulado/análise , Emissões de Veículos/análise , Cidades , Humanos , Medição de Risco , Vietnã
5.
Ecotoxicol Environ Saf ; 200: 110774, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32460055

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants in atmosphere, which attracted more attentions due to their influence on human health. In this study, a national scale cancer risk (CR) assessment with atmospheric PAHs were conducted based on one year monitoring program at 11 cities across China. The annual mean concentrations of benzo[a]pyrene (BaP) and BaP equivalency (BaPeq) were 4.56 ± 7.78 ng/m3 and 8.45 ± 14.1 ng/m3, respectively, which were both higher than the new ambient air quality standards of China (GB 3095-2012, 1 ng/m3). Concentrations of BaP and BaPeq in northern Chinese cities were almost 2 times higher than those in southern Chinese cities. The CR values induced by the dermal contact exposure were two orders of magnitude higher than that by the inhalation exposure. Children and adults were the most sensitive age groups with the dermal contact exposure and the inhalation exposure to atmospheric PAHs, respectively. For the total CR values, 99.7% of its values were higher than the reference level of 10-6. No significant difference of the total CR values was observed between northern Chinese and southern Chinese cities for children and adults. In order to quantify the uncertainties of CR assessment, Monte Carlo Simulation was applied based on the specific distributions of the exposure factors cited from the Exposure Factors Handbook of Chinese Population. The results indicated that almost 90% probability of the total CR values were higher than 10-6, indicating potential cancer risk. Sensitive analysis indicated that atmospheric concentration, outdoor exposure fraction, particle amount adhered to skin, and cancer slope factor should be carefully considered in order to increase the accuracy of CR assessment with PAHs in atmosphere.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Atmosfera/química , Monitoramento Ambiental/métodos , Exposição por Inalação/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Adolescente , Adulto , Criança , China , Cidades , Humanos , Exposição por Inalação/efeitos adversos , Método de Monte Carlo , Neoplasias/epidemiologia , Probabilidade , Medição de Risco
6.
Toxicol Appl Pharmacol ; 400: 115041, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32428593

RESUMO

Respiratory ailments have plagued occupational and public health communities exposed to World Trade Center (WTC) dust since the September 11, 2001 attack on the Twin Towers in Lower Manhattan. We proposed that these ailments were proposed to be induced by inhalation exposure to WTC particulate matter (WTCPM), that was released during the collapse of the buildings and its subsequent resuspension during cleanup. We investigated this hypothesis using both an in vitro and an in vivo mouse intranasal (IN) exposure models to identify the inflammatory potential of WTCPM with specific emphasis on respiratory and endothelial tissue responses. The in vitro exposure studies found WTCPM exposure to be positively correlated with cytotoxicity and increased NO2- production in both BEAS-2B pulmonary epithelial cells and THP-1 macrophage cells. The in vivo C57BL/6 mouse studies found significant increases in inflammatory markers including increases in polymorphonuclear neutrophil (PMN) influx into nasal and bronchoalveolar lavage fluids (NLF and BALF), as well as increased levels of total protein and cytokine/chemokines levels. Concurrently, NLF, BALF, and serum NO2- levels exhibited significant homeostatic temporal deviations as well as temporal myograohic aortic dysfunction in myography studies. Respiratory exposure to- and evidence -based retention of- WTCPM may have contributed to chronic systemic effects in exposed mice that r resembled to observed effects in WTCPM-exposed human populations. Collectively, these findings are reflective of WTCPM exposure and its effect(s) on respiratory and aortic tissues, highlighting potential dysfunctional pathways that may precipitate inflammatory events, while simultaneously altering homeostatic balances. The tight interplay between these balances, when chronically altered, may contribute to- or result in- chronically diseased pathological states.


Assuntos
Poluentes Atmosféricos/toxicidade , Materiais de Construção/toxicidade , Poeira/análise , Endotélio Vascular/efeitos dos fármacos , Exposição por Inalação/efeitos adversos , Pneumonia/induzido quimicamente , Poluentes Atmosféricos/análise , Animais , Aorta/efeitos dos fármacos , Aorta/fisiopatologia , Biomarcadores/sangue , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Materiais de Construção/análise , Endotélio Vascular/fisiopatologia , Humanos , Exposição por Inalação/análise , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Camundongos Endogâmicos C57BL , Cavidade Nasal/efeitos dos fármacos , Cavidade Nasal/imunologia , Cidade de Nova Iorque , Ataques Terroristas de 11 de Setembro , Células THP-1
7.
Ecotoxicol Environ Saf ; 197: 110592, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32298857

RESUMO

Cooking exhaust gas includes polycyclic aromatic hydrocarbons (PAHs) that are unintentionally generated during cooking, which exposes the cook and others in the vicinity to these toxic compounds. However, information on the occurrence of PAHs, particularly their chlorinated derivatives (ClPAHs), in cooking exhaust gas is limited. Here, we determined the concentrations of 12 PAHs and 20 ClPAHs in cooking exhaust gas emitted during gas-grilling of a Pacific saury using a typical Japanese fish grill in an indoor kitchen. The total concentrations of PAHs and ClPAHs in the cooking exhaust gas were 3400 and 19 ng m-3, respectively. All 12 PAHs were detected in the cooking exhaust gas, with phenanthrene (2100 ng m-3), fluorene (630 ng m-3), and anthracene (200 ng m-3) detected at the highest concentrations. Four of the 20 ClPAHs were detected, with 9-monochlorinated phenanthrene detected at the highest concentration (12 ng m-3). The exposure rates for the cook to the PAHs and ClPAHs in the cooking exhaust gas, estimated using the National Institute of Advanced Industrial Science and Technology - Indoor Consumer Exposure Assessment Tool (AIST-ICET), were in the range of 7.2-72 ng-BaPeq kg-1 day-1 (toxic equivalent concentrations relative to the toxicity of benzo[a]pyrene), which was comparable with that for dietary ingestion of cooked foods (54 ng-BaPeq kg-1 day-1). A risk assessment of exposure to PAHs and ClPAHs in cooking exhaust gas in the indoor environment revealed that this gas may pose a health risk to the cook (incremental lifetime cancer risk: 2.1 × 10-6 to 2.1 × 10-5), indicating that further investigations are warranted.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Culinária/instrumentação , Exposição por Inalação/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Atmosféricos/química , Poluentes Atmosféricos/toxicidade , Monitoramento Ambiental , Halogenação , Humanos , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Medição de Risco
8.
Ecotoxicol Environ Saf ; 196: 110526, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32224369

RESUMO

Atmospheric monitoring data of polycyclic aromatic hydrocarbons (PAHs) over a three-year period were collected from an urban site in Dalian, northeast China. The status of PAHs in the atmosphere in Dalian were evaluated by assessing concentration levels, congener profiles, seasonal trends, primary source, inhalation exposure and the risk of developing lung cancer risk. Average concentrations were recorded for 53 PAHs (95 ± 40 ng/m3), 16 EPA priority PAHs (68 ± 33 ng/m3), 26 alkylated PAHs (17 ± 7.6 ng/m3) and 4 high-molecular-weight (302 Da) PAHs (1.3 ± 1.3 ng/m3). Atmospheric PAH concentrations in winter were almost twice as high as those recorded in the summer, possibly due to enhanced local emissions and long-range transport of atmospheric PAHs during the winter. PAH congeners were dominated by phenatherene, fluoranthene, pyrene and fluorene, accounting for 46.0% of total ∑53PAH concentrations. Ship/vehicle emission and mixed combustion were identified as the main sources of PAHs using diagnostic PAH concentration ratios and principal component analysis-multiple linear regression. Benzo(a)pyrene toxicity equivalent concentration had an average content of 32 ± 37 ng/m-3 over the sampling period, with dibenzo(a,h)anthracene (50.7%) and dibenzo(a,l)pyrene (26.4%) being the largest contributors. The risk of developing lung cancer due to inhalation exposure to outdoor PAHs was calculated at 12.0‰ using the overall population attributable fraction (PAF). Our results estimate that, due to PAH exposure in Dalian, the average excess lung cancer risk during a person's lifetime is 35.7 cancer cases per one million inhabitants.


Assuntos
Poluentes Atmosféricos/análise , Exposição por Inalação/análise , Neoplasias Pulmonares/epidemiologia , Hidrocarbonetos Policíclicos Aromáticos/análise , Estações do Ano , Emissões de Veículos/análise , Atmosfera/química , China , Cidades , Humanos , Risco
9.
Toxicol Lett ; 328: 52-60, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32320776

RESUMO

Ambient PM2.5 was collected during the winter season from Taiyuan, Shanxi, China; Jinan, Shandong, China; and Sacramento, California, USA, and used to create PMSX, PMSD, and PMCA extracts, respectively. Time-lag experiments were performed to explore the in vivo and in vitro toxicity of the PM extracts. In vivo inflammatory lung responses were assessed in BALB/c mice using a single oropharyngeal aspiration (OPA) of PM extract or vehicle (CTRL) on Day 0. Necropsies were performed on Days 1, 2, and 4 post-OPA, and pulmonary effects were determined using bronchoalveolar lavage (BAL) and histopathology. On Day 1, BAL neutrophils were significantly elevated in all PM- versus CTRL-exposed mice, with PMCA producing the strongest response. However, histopathological scoring showed greater alveolar and perivascular effects in PMSX-exposed mice compared to all three other groups. By Day 4, BAL neutrophilia and tissue inflammation were resolved, similar across all groups. In vitro effects were examined in human HepG2 hepatocytes, and U937 cells following 6, 24, or 48 h of exposure to PM extract or DMSO (control). Luciferase reporter and quantitative polymerase chain reaction assays were used to determine in vitro effects on aryl hydrocarbon receptor (AhR) activation and gene transcription, respectively. Though all three PM extracts activated AhR, PMSX produced the greatest increases in AhR activation, and mRNA levels of cyclooxygenase-2, cytochrome P450, interleukin (IL)-8, and interleukin (IL)-1ß. These effects were assumed to result from a greater abundance of polycyclic aromatic hydrocarbons (PAHs) in PMSX compared to PMSD and PMCA.


Assuntos
Poluentes Atmosféricos/toxicidade , Monitoramento Ambiental/métodos , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Material Particulado/toxicidade , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , California , China , Citocinas/metabolismo , Células Hep G2 , Humanos , Exposição por Inalação/efeitos adversos , Exposição por Inalação/análise , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Receptores de Hidrocarboneto Arílico/genética , Transcrição Genética/efeitos dos fármacos , Células U937
10.
Environ Sci Pollut Res Int ; 27(17): 21654-21665, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32279249

RESUMO

Arsenic in fine air particulate matter (PM2.5) has been identified as an important factor responsible for the morbidity of lung cancer, which has increased sharply in many regions of China. Some reports in China have shown that arsenic in the air exceeds the ambient air quality standard value, while long-term airborne arsenic concentrations in central China and human exposure via inhalation of PM-bound arsenic (inhalable airborne PM) have not been well characterized. In this study, 579 outdoor air PM2.5 samples from Wuhan, a typical city in central China, were collected from 2015 to 2017, and arsenic was measured by inductively coupled plasma-mass spectrometry. Personal exposure to PM-bound arsenic via inhalation and urinary arsenic concentration were also measured. The concentrations of arsenic in PM2.5 were in the range of 0.42-61.6 ng/m3 (mean 8.48 ng/m3). The average concentration of arsenic in 2015 (10.7 ng/m3) was higher than that in 2016 (6.81 ng/m3) and 2017 (8.18 ng/m3), exceeded the standard value. The arsenic concentrations in spring and winter were higher than those in summer and autumn. No significant differences (p > 0.05) were found among different sites. The daily intake of arsenic inhalation based on PM10 samples collected by personal samplers (median, 10.8 ng/m3) was estimated. Urban residents inhaled higher levels of PM-bound arsenic than rural residents. Daily intake of arsenic via inhalation accounted for a negligible part (< 1%) of the total daily intake of arsenic (calculated based on excreted urinary arsenic); however, potential associations between the adverse effects (e.g., lung adenocarcinoma) and inhaled PM-bound arsenic require more attention, particularly for those who experience in long-term exposure. This study is the first report of a 3-year temporal trend of airborne PM2.5-bound arsenic in central China.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Arsênico , China , Cidades , Monitoramento Ambiental , Humanos , Exposição por Inalação/análise , Material Particulado/análise , Estações do Ano
11.
Bull Environ Contam Toxicol ; 104(6): 786-791, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32333044

RESUMO

This study aims to determine BTEX concentrations in the Metropolitan Region of Rio de Janeiro (MRRJ, Brazil) and evaluate potential health risks of benzene and ethylbenzene exposure based on the collected data, in 2015, the year before the Rio 2016 Olympic Games. Samples were collected and analyzed following method TO-15 (U.S.EPA). Toluene was the most abundant compound in all samples (mean concentration 16.72 ± 15.70 µg m-3). The average benzene concentration in ambient air (3.44 ± 3.14 µg m-3) was slightly lower than the yearly average "upper assessment threshold", 3.5 µg m-3, established by EU Directive 2008/50/EC. The calculated cancer risk values were > 1 × 10-6 for all samples, clearly indicating a potential cancer risk and the importance of fixed measurements by the monitoring stations to assess ambient air quality in the urban areas of the MRRJ. Calculated ratios for the BTEX species indicate that these compounds are predominantly emitted from vehicular sources with a contribution from industrial sources.


Assuntos
Poluentes Atmosféricos/análise , Derivados de Benzeno/análise , Benzeno/análise , Monitoramento Ambiental/métodos , Exposição por Inalação/análise , Tolueno/análise , Xilenos/análise , Brasil , Cidades , Humanos , Medição de Risco
12.
Ecotoxicol Environ Saf ; 196: 110571, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32276159

RESUMO

Environmentally persistent free radicals (EPFRs) was considered unrecognized composition of air pollutants and might help explain the long-standing medical mystery of why non-smokers develop tobacco-related diseases like lung cancer. EPFRs in airborne fine particulate matter (PM2.5) can induce oxidative and DNA damage when inhaled. We assessed the inhalation risk of EPFRs in PM2.5 and factors influencing this risk in Beijing as a large city with frequent haze events. The average concentration of EPFRs in PM2.5 was 6.00 × 1017 spins/m3 in spring, autumn, and winter; lower concentrations were recorded in the summer. To estimate the daily inhalation risk of EPFRs in PM2.5, we used the equivalent EPFRs in cigarette tar. The average daily inhalation exposure of EPFRs in PM2.5 was estimated to be the equivalent of 33.1 cigarette tar EPFRs per day (range: 0.53-226.9) during both haze and non-haze days. The major factors influencing EPFR concentrations in the atmosphere were precipitation and humidity, which reduced airborne concentrations. Levels of PM2.5 and carbon monoxide were positively correlated with EPFR concentrations. The health risks of inhaling airborne EPFRs could be significant and should be recognized and quantified.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Radicais Livres/análise , Exposição por Inalação/análise , Material Particulado/análise , Atmosfera/química , Pequim , Humanos , Oxirredução , Medição de Risco , Estações do Ano , Alcatrões/química
13.
Am J Public Health ; 110(5): 655-661, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32191524

RESUMO

Objectives. To investigate potential changes in burdens from coal-fired electricity-generating units (EGUcfs) that emit fine particulate matter (PM2.5, defined as matter with a nominal mean aerodynamic diameter of ≤ 2.5 µm) among racial/ethnic and economic groups after reduction of operations in 92 US EGUcfs.Methods. PM2.5 burdens calculated for EGUs listed in the 2008, 2011, and 2014 National Emissions Inventory were recalculated for 2017 after omitting emissions from 92 EGUcfs. The combined influence of race/ethnicity and poverty on burden estimates was characterized.Results. Omission of 92 EGUcfs decreased PM2.5 burdens attributable to EGUs by 8.6% for the entire population and to varying degrees for every population subgroup. Although the burden decreased across all subgroups, the decline was not equitable. After omission of the 92 EGUcfs, burdens were highest for the below-poverty and non-White subgroups. Proportional disparities between White and non-White subgroups increased. In our combined analysis, the burden was highest for the non-White-high-poverty subgroup.Conclusions. Our results indicate that subgroups living in poverty experience the greatest absolute burdens from EGUcfs. Changes as a result of EGUcf closures suggest a shift in burden from White to non-White subgroups. Policymakers could use burden analyses to jointly promote equity and reduce emissions.


Assuntos
Carvão Mineral , Grupos de Populações Continentais/estatística & dados numéricos , Grupos Étnicos/estatística & dados numéricos , Material Particulado/análise , Pobreza/estatística & dados numéricos , Centrais Elétricas/estatística & dados numéricos , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Exposição Ambiental/análise , Humanos , Exposição por Inalação/análise , Método de Monte Carlo , Características de Residência
14.
Nanotoxicology ; 14(4): 554-576, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32216600

RESUMO

No detailed information on in vivo biokinetics of CeO2 nanoparticles (NPs) following chronic low-dose inhalation is available. The CeO2 burden for lung, lung-associated lymph nodes, and major non-pulmonary organs, blood, and feces, was determined in a chronic whole-body inhalation study in female Wistar rats undertaken according to OECD TG453 (6 h per day for 5 days per week for a 104 weeks with the following concentrations: 0, 0.1, 0.3, 1.0, and 3.0 mg/m3, animals were sacrificed after 3, 12, 24 months). Different spectroscopy methods (ICP-MS, ion-beam-microscopy) were used for the quantification of organ burden and for visualization of NP distribution patterns in tissues. After 24 months of exposure, the highest CeO2 lung burden (4.41 mg per lung) was associated with the highest aerosol concentration and was proportionally lower for the other groups in a dose-dependent manner. Imaging techniques confirmed the presence of CeO2 agglomerates of different size categories within lung tissue with a non-homogenous distribution. For the highest exposure group, after 24 months in total 1.2% of the dose retained in the lung was found in the organs and tissues analyzed in this study, excluding lymph nodes and skeleton. The CeO2 burden per tissue decreased from lungs > lymph nodes > hard bone > liver > bone marrow. For two dosage groups, the liver organ burden showed a low accumulation rate. Here, the liver can be regarded as depot, whereas kidneys, the skeleton, and bone marrow seem to be dumps due to steadily increasing NP burden over time.


Assuntos
Cério/farmacocinética , Exposição por Inalação/análise , Pulmão/metabolismo , Linfonodos/metabolismo , Nanopartículas/metabolismo , Aerossóis , Animais , Carga Corporal (Radioterapia) , Cério/sangue , Relação Dose-Resposta a Droga , Fezes/química , Feminino , Fígado/efeitos dos fármacos , Fígado/metabolismo , Pulmão/efeitos dos fármacos , Modelos Biológicos , Especificidade de Órgãos , Tamanho da Partícula , Ratos , Ratos Wistar , Propriedades de Superfície , Distribuição Tecidual
15.
Nanotoxicology ; 14(5): 595-611, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32091294

RESUMO

Carbon black nanoparticles (CBNPs) can enter the central nervous system through blood circulation and olfactory nerves, affecting brain development or increasing neurological disease susceptibility. However, whether CBNPs exposure affects seizure is unclear. Herein, mice were exposed to two different doses of CBNPs (21 and 103 µg/animal) based on previous studies and the maximum exposure limitation (4 mg/m3) in occupational workplaces set by the Chinese government. In the pentylenetetrazol (PTZ) and kainic acid (KA) seizure models, high-dose CBNPs exposure increased seizure susceptibility in both models and increased spontaneous recurrent seizure (SRS) frequency in the KA model. In vivo local field potential (LFP) recording in KA model mice revealed that both low-dose and high-dose CBNPs exposure increased seizure-like event (SLE) frequency in the SRS interval but shortened SLE duration. Intriguingly, H&E staining and Nissl staining on brain tissue revealed that CBNPs exposure did not cause significant brain tissue morphology or neuronal damage. Detection of inflammatory factors, such as TNF-α, TGF-ß1, IL-1ß, and IL-6, in brain tissue showed that only high dose of CBNPs exposure increased the expression of cortical TGF-ß1. By using the primary cultured neurons, we observed that CBNPs exposure not only significantly decreased the expression of the neuronal marker MAP2 but also enhanced the levels of action potential frequency in the neurons. In general, CBNPs exposure can affect abnormal epileptic discharges during the seizure interval and enhance susceptibility to frequent seizures. Our findings suggest that minimizing CBNPs exposure may be a potential way to prevent or ease seizure.


Assuntos
Encéfalo/efeitos dos fármacos , Exposição por Inalação/efeitos adversos , Nanopartículas/toxicidade , Neurônios/efeitos dos fármacos , Convulsões/induzido quimicamente , Fuligem/toxicidade , Potenciais de Ação/efeitos dos fármacos , Animais , Encéfalo/imunologia , Encéfalo/patologia , Células Cultivadas , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Exposição por Inalação/análise , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/química , Neurônios/imunologia , Neurônios/patologia , Tamanho da Partícula , Técnicas de Patch-Clamp , Recidiva , Convulsões/patologia , Fuligem/química , Propriedades de Superfície
16.
Ecotoxicol Environ Saf ; 191: 110212, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32006868

RESUMO

Since many household products used by individuals contain flame retardants (FRs), there is more chance that these chemicals may be present in the various exhibit of the indoor environment. Despite being one of the fastest-growing economies worldwide, the contamination level, sources, products, and pathways of FRs in India, is either not known or limited. This inspired us to investigate the level, profile, spatial distribution, and sources of different classes of FRs in the indoor air. For this purpose, 15 brominated, 2 chlorinated, and 8 organophosphate FRs (OPFRs) were investigated in indoor air samples from urban and suburban sites of an Indian state of Bihar. Additionally, inhalation health risk exposure to children and the adult was estimated to predict the risk of these chemicals. Overall, ∑8OPFRs (median 351 pg/m3) was the most prominent in air, followed by novel brominated FR (∑6NBFRs) (median 278 pg/m3), polybrominated diphenyl ether (∑9PBDE) (median 5.05 pg/m3), and dechlorane plus (∑2DPs) (median 2.52 pg/m3), and accounted for 55%, 44%, 0.8% and 0.4% of ∑FRs, respectively. Generally, ∑9PBDEs (median 6.29 pg/m3) and ∑8OPFRs (median 355 pg/m3) were measured high at sub-urban sites, while urban sites had the highest level of ∑2DPs (median 2.81 pg/m3) and ∑6NBFRs (median 740 pg/m3). BDE-209 was most abundant among ∑9PBDEs, while syn-DP dominated in ∑2DPs. Likewise, DBDPE was most prevalent in ∑6NBFRs, while TMPP topped among ∑8OPFRs. The principal component analysis revealed contribution from household items, food packaging and paints, hydraulic fluid, a gasoline additive, and de-bromination of BDE-209 as the primary sources of FRs. The estimated daily inhalation exposure (DIE) indicated a relatively high risk to children than the adult. The DIE of individual FR was several folds lower than their corresponding oral reference dose (RfDs), suggesting minimal risk. However, exposure risk, especially to children, may still need attention because other routes of intake may always be significant in the case of Bihar.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Retardadores de Chama/análise , Hidrocarbonetos Halogenados/análise , Exposição por Inalação/análise , Organofosfatos/análise , Humanos , Hidrocarbonetos Halogenados/química , Índia , Organofosfatos/química , Análise de Componente Principal , Medição de Risco
17.
Nanotoxicology ; 14(3): 404-419, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32031476

RESUMO

The objective of this study was to evaluate the association between carbon nanotube and nanofiber (CNT/F) exposure and ex vivo responses of whole blood challenged with secondary stimulants, adjusting for potential confounders, in a cross-sectional study of 102 workers. Multi-day exposure was measured by CNT/F structure count (SC) and elemental carbon (EC) air concentrations. Demographic, lifestyle and other occupational covariate data were obtained via questionnaire. Whole blood collected from each participant was incubated for 18 hours with and without two microbial stimulants (lipopolysaccharide/LPS and staphylococcal enterotoxin type B/SEB) using TruCulture technology to evaluate immune cell activity. Following incubation, supernatants were preserved and analyzed for protein concentrations. The stimulant:null response ratio for each individual protein was analyzed using multiple linear regression, followed by principal component (PC) analysis to determine whether patterns of protein response were related to CNT/F exposure. Adjusting for confounders, CNT/F metrics (most strongly, the SC-based) were significantly (p < 0.05) inversely associated with stimulant:null ratios of several individual biomarkers: GM-CSF, IFN-γ, interleukin (IL)-2, IL-4, IL-5, IL-10, IL-17, and IL-23. CNT/F metrics were significantly inversely associated with PC1 (a weighted mean of most biomarkers, explaining 25% of the variance in the protein ratios) and PC2 (a biomarker contrast, explaining 14%). Among other occupational exposures, only solvent exposure was significant (inversely related to PC2). CNT/F exposure metrics were uniquely related to stimulant responses in challenged whole blood, illustrating reduced responsiveness to a secondary stimulus. This approach, if replicated in other exposed populations, may present a relatively sensitive method to evaluate human response to CNT/F or other occupational exposures.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Citocinas/sangue , Exposição por Inalação/efeitos adversos , Nanofibras/toxicidade , Nanotubos de Carbono/toxicidade , Exposição Ocupacional/efeitos adversos , Adulto , Poluentes Ocupacionais do Ar/análise , Biomarcadores/sangue , Estudos Transversais , Feminino , Humanos , Exposição por Inalação/análise , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Nanofibras/análise , Nanotubos de Carbono/análise , Exposição Ocupacional/análise , Análise de Componente Principal , Escarro/química , Escarro/imunologia
18.
Occup Environ Med ; 77(4): 268-275, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32034033

RESUMO

OBJECTIVES: Since 2000 the European Industrial Minerals Association's Dust Monitoring Programme (IMA-DMP) has systematically collected respirable dust and respirable quartz measurements from 35 companies producing industrial minerals. The IMA-DMP initiative allowed for estimating overall temporal trends in exposure concentrations for the years 2002-2016 and for presenting these trends by type of mineral produced, by jobs performed and by time of enrolment into the DMP. METHODS: Approximately 32 000 personal exposure measurements were collected during 29 sampling campaigns during a 15-year period (2002-2016). Temporal trends in respirable dust and respirable quartz concentrations were studied by using linear mixed effects models. RESULTS: Concentrations varied widely (up to three to four orders of magnitude). However, overall decreases in exposure levels were shown for the European minerals industry over the 15-year period. Statistically significant overall downward temporal trends of -9.0% and -3.9% per year were observed for respirable dust and respirable quartz, respectively. When analyses were stratified by time period, no downward trends (and even slight increasing concentrations) were observed between 2008 and 2012, most likely attributable to the recent global economic crisis. After this time period, downward trends became visible again. CONCLUSIONS: Consistent and statistically significant downward trends were found for both exposure to respirable dust and respirable quartz. These downward trends became less or even reversed during the years of the global economic crisis. To our knowledge, this is the first time that analyses of long-term temporal trends point at an effect of a global economic crisis on personal exposure concentrations of workers from sites across Europe.


Assuntos
Poluentes Ocupacionais do Ar/análise , Poeira/análise , Monitoramento Ambiental/métodos , Exposição por Inalação/análise , Exposição Ocupacional/análise , Quartzo/análise , Poluentes Ocupacionais do Ar/normas , Bases de Dados Factuais , Europa (Continente) , Humanos , Indústrias , Minerais , Exposição Ocupacional/normas , Exposição Ocupacional/estatística & dados numéricos
19.
Toxicol Lett ; 322: 20-31, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31923465

RESUMO

Particulate matter (PM) from combustion processes has been associated with oxidative stress to DNA, whereas effects related to telomere dysfunction are less investigated. We collected air-borne PM from a passenger cabin of a diesel-propelled train and at a training facility for smoke diving exercises. Effects on oxidative stress biomarkers, genotoxicity measured by the comet assay and telomere length in PM-exposed A549 cells were compared with the genotoxicity and telomere length in peripheral blood mononuclear cells (PBMCs) from human volunteers exposed to the same aerosol source. Although elevated levels of DNA strand breaks and oxidatively damaged DNA in terms of Fpg-sensitive sites were observed in PBMCs from exposed humans, the PM collected at same locations did not cause genotoxicity in the comet assay in A549 cells. Nevertheless, A549 cells displayed telomere length shortening after four weeks exposure to PM. This is in line with slightly shorter telomere length in PBMCs from exposed humans, although it was not statistically significant. In conclusion, the results indicate that genotoxic potency measured by the comet assay of PM in A549 cells may not predict genotoxicity in exposed humans, whereas telomere length measurements may be a novel indicator of genotoxic stress in cell cultures and humans.


Assuntos
Dano ao DNA , Exposição por Inalação/efeitos adversos , Material Particulado/toxicidade , Fumaça/efeitos adversos , Homeostase do Telômero/efeitos dos fármacos , Emissões de Veículos/toxicidade , Células A549 , Poluentes Ocupacionais do Ar/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Bombeiros , Humanos , Exposição por Inalação/análise , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/patologia , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Tamanho da Partícula , Homeostase do Telômero/genética
20.
Ecotoxicol Environ Saf ; 191: 110162, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31935557

RESUMO

It is essential and challenged to understand the atmospheric arsenic pollution because it is much more complicated than in water and top-soil. Herein the different behavior of arsenic species firstly were discovered within the ambient PM2.5 collected during daytime and nighttime, winter and summer. The diurnal variation of arsenic species in PMs is significantly correlated with the presence of metallic oxides, specifically, ferrous, titanium and zinc oxides, which might play a key role in the process of the photo-oxidation of As(III) to As(V) with the meteorological parameters and regional factors excluded. Subsequently, the photo conversion of arsenite was detected on metal-loaded glass-fiber filters under visible light. The photo-generated superoxide radical was found to be predominantly responsible for the oxidation of As(III). In order to reveal toxicity differences induced by oxidation As(III), HepG2 cells were exposed to various arsenic mixture solution. We found that the antioxidant enzyme activities suppressed with increasing the As(III)/As(V) ratio in total, followed by the accumulation of intracellular ROS level. The glucose consumption and glycogen content also displayed an obvious reduction in insulin-stimulated cells. Compared to the expression levels of IRS-1, AKT and GLUT4, GLUT2 might be more vulnerable to arsenic exposure and lead to the abnormalities of glucose metabolism in HepG2 cells. Taken together, these findings clarify that the health risk posed by inhalation exposure to As-pollution air might be alleviated owing to the photo-driven conversion in presence of metal oxides.


Assuntos
Poluentes Atmosféricos/análise , Arseniatos/análise , Arsenitos/análise , Glucose/metabolismo , Luz , Metais Pesados/análise , Material Particulado/análise , Poluentes Atmosféricos/efeitos da radiação , Poluentes Atmosféricos/toxicidade , Arseniatos/efeitos da radiação , Arseniatos/toxicidade , Arsenitos/efeitos da radiação , Arsenitos/toxicidade , Células Hep G2 , Humanos , Exposição por Inalação/análise , Modelos Teóricos , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Óxidos/análise , Material Particulado/efeitos da radiação , Material Particulado/toxicidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA