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1.
Artigo em Inglês | MEDLINE | ID: mdl-33671300

RESUMO

There is currently not sufficient evidence to support the effectiveness of face shields for source control. In order to evaluate the comparative barrier performance effect of face masks and face shields, we used an aerosol generator and a particle counter to evaluate the performance of the various devices in comparable situations. We tested different configurations in an experimental setup with manikin heads wearing masks (surgical type I), face shields (22.5 cm high with overhang under the chin of 7 cm and circumference of 35 cm) on an emitter or a receiver manikin head, or both. The manikins were face to face, 25 cm apart, with an intense particle emission (52.5 L/min) for 30 s. The particle counter calculated the total cumulative particles aspirated on a volume of 1.416 L In our experimental conditions, when the receiver alone wore a protection, the face shield was more effective (reduction factor = 54.8%), while reduction was lower with a mask (reduction factor = 21.8%) (p = 0.002). The wearing of a protective device by the emitter alone reduced the level of received particles by 96.8% for both the mask and face shield (p = NS). When both the emitter and receiver manikin heads wore a face shield, the protection allowed for better results in our experimental conditions: 98% reduction for the face shields versus 97.3% for the masks (p = 0.01). Face shields offered an even better barrier effect than the mask against small inhaled particles (<0.3 µm-0.3 to 0.5 µm-0.5 to 1 µm) in all configurations. Therefore, it would be interesting to include face shields as used in our experimental study as part of strategies to reduce transmission within the community setting.


Assuntos
Controle de Doenças Transmissíveis/instrumentação , Exposição por Inalação/prevenção & controle , Máscaras , Equipamento de Proteção Individual , Aerossóis , Humanos
2.
Sensors (Basel) ; 21(5)2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33668116

RESUMO

Smoke inhalation poses a serious health threat to firefighters (FFs), with potential effects including respiratory and cardiac disorders. In this work, environmental and physiological data were collected from FFs, during experimental fires performed in 2015 and 2019. Extending a previous work, which allowed us to conclude that changes in heart rate (HR) were associated with alterations in the inhalation of carbon monoxide (CO), we performed a HR analysis according to different levels of CO exposure during firefighting based on data collected from three FFs. Based on HR collected and on CO occupational exposure standards (OES), we propose a classifier to identify CO exposure levels through the HR measured values. An ensemble of 100 bagged classification trees was used and the classification of CO levels obtained an overall accuracy of 91.9%. The classification can be performed in real-time and can be embedded in a decision fire-fighting support system. This classification of FF' exposure to critical CO levels, through minimally-invasive monitored HR, opens the possibility to identify hazardous situations, preventing and avoiding possible severe problems in FF' health due to inhaled pollutants. The obtained results also show the importance of future studies on the relevance and influence of the exposure and inhalation of pollutants on the FF' health, especially in what refers to hazardous levels of toxic air pollutants.


Assuntos
Monóxido de Carbono/análise , Bombeiros , Frequência Cardíaca , Exposição por Inalação/análise , Exposição Ocupacional/análise , Fogo , Humanos , Fumaça/análise
3.
Ecotoxicol Environ Saf ; 214: 112071, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33690004

RESUMO

PM2.5 and PM10 samples were collected from the outdoor environment of five types of cities (provincial central cities, regional central cities, resource-based cities, agricultural cities, and forested cities) situated in Northeast China. Based on bioaccessibility and respiratory deposition fluxes, health risks of PM2.5- and PM10-bound six heavy metals [HM6: Arsenic (As), Chromium (Cr), Cadmium (Cd), Nickel (Ni), Cobalt (Co), and Lead (Pb)] were studied. Cobalt (Co) and Cr were found to be the most abundantly bioaccessible fraction among HM6 after extraction of simulated lung fluids. After inhalation exposure, among HM6, Co mainly contributed 88.39-93.19% to the non-carcinogenic risk, while Cr account for 82.92-93.72% of cancer risk. The estimated daily intake of bioaccessible HM6 in outdoor environment during the heating period was calculated to be 293.11 ± 121.03, 117.08 ± 32.46, 105.57 ± 32.49, 100.35 ± 25.58 and 83.11 ± 17.64 ng/h for provincial central cities, regional central cities, agricultural city, resource-based cities and forested cities, respectively, for local residents. During the heating period of 180 days, non-carcinogenic risks (As, Cr, Cd, Ni, Co) in outdoor environment of 0.5 residence time were below the safety threshold (HQ < 1). Cancer risks for Cr and Co were above 10-5 in the five types of cities, but in the assumable range (< 10-4). Our study highlighted the wide range of measures needed to cut airborne particles pollution to safer levels.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Material Particulado/análise , Poluição do Ar/estatística & dados numéricos , Arsênico , China , Cidades , Poluição Ambiental , Calefação , Humanos , Exposição por Inalação , Metais Pesados/análise , Medição de Risco , Estações do Ano
4.
Medicine (Baltimore) ; 100(10): e25054, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33725891

RESUMO

ABSTRACT: Waterproofing spray-associated pneumonitis (WAP) proceeds to acute respiratory failure and is characterized by diffuse bilateral ground-glass opacities on computed tomography; however, the detailed characteristics of WAP are unknown. Therefore, this study identified the characteristics of WAP from comparisons with those of acute eosinophilic pneumonia (AEP) and hypersensitivity pneumonitis (HP), which show similar features to WAP.Adult patients with WAP, AEP, and HP treated in Fukujuji Hospital from 1990 to 2018 were retrospectively enrolled. Furthermore, data from patients with WAP were collected from publications in PubMed and the Japan Medical Abstracts Society and combined with data from our patients.Thirty-three patients with WAP, eleven patients with AEP, and thirty patients with HP were reviewed. Regarding age, sex, smoking habit, and laboratory findings (white blood cell count, C-reactive protein level, and serum Krebs von den Lungen-6 level), WAP and AEP were not significantly different, while WAP and HP were significantly different. The duration from symptom appearance to hospital visit was shorter in patients with WAP (median 1 day) than in patients with AEP (median 3 days, P = .006) or HP (median 30 days, P < .001). The dominant cells in the bronchoalveolar lavage fluid of patients with WAP, AEP, and HP were different (macrophages, eosinophils, and lymphocytes, respectively).The characteristic features of WAP were rapid disease progression and macrophage dominance in the bronchoalveolar lavage fluid, and these characteristics can be used to distinguish among WAP, AEP, and HP.


Assuntos
Lesão Pulmonar Aguda/diagnóstico , Alveolite Alérgica Extrínseca/diagnóstico , Polímeros de Fluorcarboneto/efeitos adversos , Eosinofilia Pulmonar/diagnóstico , Insuficiência Respiratória/etiologia , Lesão Pulmonar Aguda/sangue , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/complicações , Adolescente , Adulto , Idoso , Alveolite Alérgica Extrínseca/sangue , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Proteína C-Reativa/análise , Diagnóstico Diferencial , Progressão da Doença , Feminino , Humanos , Exposição por Inalação/efeitos adversos , Contagem de Leucócitos , Macrófagos/imunologia , Masculino , Pessoa de Meia-Idade , Mucina-1/sangue , Eosinofilia Pulmonar/sangue , Estudos Retrospectivos , Adulto Jovem
5.
Artigo em Chinês | MEDLINE | ID: mdl-33535337

RESUMO

Objective: To explore the effect of cabinet type water curtain exhaust hood applied to small sandblasting machine to prevent and control silicon dust, and put forward a new idea of dust ventilation protection facilities to effectively protect the occupational health of workers. Methods: From August to October 2018, the cabinet type water curtain exhaust hood of sandblasting room in a research institute was selected as the research object, and the methods of occupational health survey, on-site detection and physical simulation of air distribution were used to conduct on-site detection and smoke emission test on the local exhaust facilities, silica dust concentration, control wind speed and air distribution before and after the transformation line analysis and evaluation. Results: The air distribution simulation experiment showed that the air distribution of the cabinet type water curtain exhaust hood was reasonable and could effectively control the whole range of silica dust emission during the cleaning process. After modification, the capture velocity was increased from 0.01 m/s to 0.53 m/s, and the capture velocity was increased by 98.1%. The time weighted average allowable concentration (C(TWA)) of silicon dust (total dust) during sand blasting, cabin opening and cleaning was reduced from 7.00 mg/m(3) to 0.50 mg/m(3). The C(TWA) of silica dust (exhalation dust) was decreased from 3.36 mg/m(3) to 0.27 mg/m(3), and the C(TWA) dust reduction rates of total dust and respirable dust were 92.9% and 92.0%, respectively. Conclusion: The combination of cabinet type exhaust hood and water curtain dedusting optimizes the combination mode of dust prevention and control. It has the advantages of high efficiency of dedusting and purification, energy saving and environmental protection, and can be popularized and used in enterprises of the same nature.


Assuntos
Poluentes Ocupacionais do Ar , Exposição Ocupacional , Poluentes Ocupacionais do Ar/análise , Poeira/análise , Desenho de Equipamento , Humanos , Exposição por Inalação , Exposição Ocupacional/análise , Exposição Ocupacional/prevenção & controle , Silício , Dióxido de Silício/análise , Água
6.
Chemosphere ; 272: 129650, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33486452

RESUMO

Oil and natural gas (O&G) extraction operations emit hazardous volatile organic compounds (VOCs) in quantities that have adverse effects on human health. Our current understanding of the exposure risks associated with upstream O&G exploitations remains limited, and very few quantitative on-site remediation strategies have been proposed. To this end, we assessed the health risks associated with the emission of hazardous VOCs and presented a set of remediation goals for the city of Calgary, which is a major center of the Canadian oil industry. Results from probabilistic risk assessment (PRA) suggested that although VOCs had a negligible impact on chronic non-cancer-associated risk, inhalation-associated cancer risk remained a significant concern. Carbon tetrachloride, benzene, and 1,3-butadiene were the dominant VOCs, representing 88% of the integrated inhalation cancer risk (= 7.8 × 10-5); background, solid fuel combustion, and O&G extraction were among the primary sources that posed the greatest threat to human health. Results of a Monte Carlo simulation revealed that the probability of developing cancer due to inhalation of hazardous VOCs was ∼13.1% on clean air days and 45.9% on days with significant levels of air pollution. Preliminary remediation goals (PRGs) included reductions of 24.2-65.1% and 11.4-50.9% targeting priority VOCs and their sources, respectively. Taken together, our findings suggest that stringent control of the sources of VOCs, particularly fossil fuel combustion, is an urgent priority. PRA coupled with PRGs provides informative risk assessments and suggests quantitative remediation strategies that can be applied toward improved management of hazardous pollutants.


Assuntos
Poluentes Atmosféricos , Neoplasias , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Canadá , Monitoramento Ambiental , Humanos , Exposição por Inalação/análise , Neoplasias/induzido quimicamente , Neoplasias/epidemiologia , Medição de Risco , Compostos Orgânicos Voláteis/análise
7.
Ecotoxicol Environ Saf ; 211: 111959, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33486383

RESUMO

Indoor biomass burning produces large amounts of small particles and hazardous contaminants leading to severe air pollution and potentially high health risks associated with inhalation exposure. Personal samplers provide more accurate estimates of inhalation exposure. In this study, inhalation exposure to size-segregated particles and particulate polycyclic aromatic hydrocarbons (PAHs) for the biomass user was studied by deploying personal samplers. The study found that daily PM2.5 inhalation exposure level was as high as 121 ± 96 µg/m3, and over 84% was finer PM1.0. For PAHs, the exposure level was 113 ± 188 ng/m3, with over 77% in PM1.0. High molecular weight PAHs with larger toxic potentials enriched in smaller particles resulting in much high risks associated with PAHs inhalation exposure. Indoor exposure contributed to ~80% of the total inhalation exposure as a result of high indoor air pollution and longer residence spent indoor. The highest exposure risk was found for the male smoker who conducted cooking activities at home.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental , Exposição por Inalação/estatística & dados numéricos , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluição do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Biomassa , Carvão Mineral/análise , Culinária , Poeira , Habitação , Humanos , Exposição por Inalação/análise , Tamanho da Partícula , População Rural , Tibet
8.
Int J Mol Sci ; 22(1)2021 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-33401533

RESUMO

Rats were exposed to nickel oxide nano-aerosol at a concentration of 2.4 ± 0.4 µg/m3 in a "nose only" inhalation setup for 4 h at a time, 5 times a week, during an overall period of 2 weeks to 6 months. Based on the majority of the effects assessed, this kind of exposure may be considered as close to LOAEL (lowest observed adverse effect level), or even to NOAEL (no observed adverse effect level). At the same time, the experiment revealed genotoxic and allergic effects as early as in the first weeks of exposure, suggesting that these effects may have no threshold at all.


Assuntos
Exposição por Inalação/efeitos adversos , Pulmão/patologia , Nanopartículas/toxicidade , Níquel/toxicidade , Medição de Risco/métodos , Animais , Feminino , Pulmão/efeitos dos fármacos , Nível de Efeito Adverso não Observado , Ratos
9.
Int J Mol Sci ; 22(2)2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33429876

RESUMO

Iron is typically the dominant metal in the ultrafine fraction of airborne particulate matter. Various studies have investigated the toxicity of inhaled nano-sized iron oxide particles (FeOxNPs) but their results have been contradictory, with some indicating no or minor effects and others finding effects including oxidative stress and inflammation. Most studies, however, did not use materials reflecting the characteristics of FeOxNPs present in the environment. We, therefore, analysed the potential toxicity of FeOxNPs of different forms (Fe3O4, α-Fe2O3 and γ-Fe2O3) reflecting the characteristics of high iron content nano-sized particles sampled from the environment, both individually and in a mixture (FeOx-mix). A preliminary in vitro study indicated Fe3O4 and FeOx-mix were more cytotoxic than either form of Fe2O3 in human bronchial epithelial cells (BEAS-2B). Follow-up in vitro (0.003, 0.03, 0.3 µg/mL, 24 h) and in vivo (Sprague-Dawley rats, nose-only exposure, 50 µg/m3 and 500 µg/m3, 3 h/d × 3 d) studies therefore focused on these materials. Experiments in vitro explored responses at the molecular level via multi-omics analyses at concentrations below those at which significant cytotoxicity was evident to avoid detection of responses secondary to toxicity. Inhalation experiments used aerosol concentrations chosen to produce similar levels of particle deposition on the airway surface as were delivered in vitro. These were markedly higher than environmental concentrations. No clinical signs of toxicity were seen nor effects on BALF cell counts or LDH levels. There were also no significant changes in transcriptomic or metabolomic responses in lung or BEAS-2B cells to suggest adverse effects.


Assuntos
Lesão Pulmonar Aguda/fisiopatologia , Inflamação/fisiopatologia , Pulmão/efeitos dos fármacos , /toxicidade , Lesão Pulmonar Aguda/induzido quimicamente , Aerossóis/química , Aerossóis/toxicidade , Poluentes Atmosféricos/toxicidade , Animais , Linhagem Celular , Humanos , Inflamação/induzido quimicamente , Exposição por Inalação , Pulmão/patologia , Material Particulado/toxicidade , Ratos , Ratos Sprague-Dawley
10.
Artigo em Inglês | MEDLINE | ID: mdl-33430311

RESUMO

Pulmonary exposure to micro- and nanoscaled particles has been widely linked to adverse health effects and high concentrations of respirable particles are expected to occur within and around many industrial settings. In this study, a field-measurement campaign was performed at an industrial manufacturer, during the production of paints. Spatial and personal measurements were conducted and results were used to estimate the mass flows in the facility and the airborne particle release to the outdoor environment. Airborne particle number concentration (1 × 103-1.0 × 104 cm-3), respirable mass (0.06-0.6 mg m-3), and PM10 (0.3-6.5 mg m-3) were measured during pouring activities. In overall; emissions from pouring activities were found to be dominated by coarser particles >300 nm. Even though the raw materials were not identified as nanomaterials by the manufacturers, handling of TiO2 and clays resulted in release of nanometric particles to both workplace air and outdoor environment, which was confirmed by TEM analysis of indoor and stack emission samples. During the measurement period, none of the existing exposure limits in force were exceeded. Particle release to the outdoor environment varied from 6 to 20 g ton-1 at concentrations between 0.6 and 9.7 mg m-3 of total suspended dust depending on the powder. The estimated release of TiO2 to outdoors was 0.9 kg per year. Particle release to the environment is not expected to cause any major impact due to atmospheric dilution.


Assuntos
Poluentes Ocupacionais do Ar , Exposição Ocupacional , Poluentes Ocupacionais do Ar/análise , Monitoramento Ambiental , Exposição por Inalação/análise , Exposição Ocupacional/análise , Pintura , Tamanho da Partícula , Titânio
11.
Chemosphere ; 262: 128330, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182093

RESUMO

Recently, there have been reports that many microplastics are found in the air, which has raised concerns about their toxicity. To date, however, only limited research has investigated the effects of micro(nano)plastics on human health, and even less the potential for inhalation toxicity. To fill this research gap, we investigated the potential inhalation toxicity of micro(nano)plastics using a modified OECD Guideline for Testing of Chemicals No. 412 '28-Day (subacute) inhalation toxicity study' using a whole-body inhalation system. Sprague-Dawley rats were exposed to three different exposure concentrations of polystyrene micro(nano)plastics (PSMPs), as well as control, for 14 days of inhalation exposure. After 14 days, alterations were observed on sevral endpoints in physiological, serum biochemical, hematological, and respiratory function markers measured on the samples exposed to PSMPs. However, no concentration-response relationships were observed, suggesting that these effects may not be definitively linked to exposure of PSMPs. On the other hand, the expression of inflammatory proteins (TGF-ß and TNF-α) increased in the lung tissue in an exposure concentration-dependent manner. The overall results indicate that 14-day inhalation exposure of PSMPs to rats has a more pronounced effect at the molecular level than at the organismal one. These results suggest that if the exposure sustained, alterations at the molecular level may lead to subsequent alterations at the higher levels, and consequently, the health risks of inhalation exposed micro(nano)plastics should not be neglected.


Assuntos
Exposição por Inalação/efeitos adversos , Pulmão/efeitos dos fármacos , Microplásticos/toxicidade , Nanopartículas/toxicidade , Poliestirenos/toxicidade , Aerossóis , Animais , Feminino , Humanos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Microplásticos/farmacocinética , Nanopartículas/metabolismo , Organização para a Cooperação e Desenvolvimento Econômico , Tamanho da Partícula , Poliestirenos/farmacocinética , Ratos , Ratos Sprague-Dawley , Testes de Função Respiratória , Propriedades de Superfície
12.
Chemosphere ; 267: 129181, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33340883

RESUMO

The bioaccessibility of metal(loid)s in ambient particulate matter (PM) has been recently used to represent the risk of inhalation exposure. Nevertheless, different methodological factors affect the bioaccessibility values; among these, the type and composition of surrogate biological fluids and the liquid to solid ratio have been revealed to be the most important. To better understand how these methodological aspects affect the bioaccessibility, a reference material corresponding to urban dust (SRM1648a) was contacted with synthetic biological fluids commonly used in the literature representing surrogate fluids that may interact with fine (Gamble's solutions, artificial lysosomal fluid (ALF)) and coarse particles (gastric fluid), for liquid to solid (L/S) ratios ranging from 500 to 20,000. Visual MINTEQ 3.1. was used to enhance the discussion on how the solubility of metals in the leaching solution depends on the composition of the simulated fluids and the speciation of metals. The results obtained indicate that a small change in the composition of Gamble's solution (the presence of glycine) may increase significantly the bioaccessibility at a L/S ratio of 5,000. The highest bioaccessibility of most of the studied metal(loid)s at a L/S ratio of 5,000 was found for ALF fluid. The study of the effect of the L/S ratio showed that metal(loid)s bioaccessibility in Gamble's fluid increased logarithmically with increasing L/S ratio, while it remained practically constant in ALF and gastric fluid. This different behavior is explained assuming that the leaching of metal(loid)s in Gamble's solution is solubility-controlled, while in ALF and gastric fluid is availability-controlled.


Assuntos
Poeira , Oligoelementos , Exposição por Inalação/análise , Metais , Material Particulado
13.
Nanotoxicology ; 15(2): 238-256, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33332178

RESUMO

Inhalation of multi-walled carbon nanotubes (MWCNTs) induces lung inflammation. Depending on industrial applications, CNTs with different physicochemical characteristics are produced and workers can potentially be exposed. This raises concerns about the long-term health effects of these nanomaterials. Because of the wide variety of MWCNTs, it is essential to study the toxicological effects of CNTs of various shapes and to better understand the impact physical and chemical properties have on their toxicity. In this study, rats were exposed by nose-only to two pristine MWCNTs with different morphologies: the long and thick NM-401 or the short and thin NM-403. After four weeks of inhalation, animals were euthanized at four different times during the recovery period: three days (short-term), 30 and 90 days (intermediate-term) and 180 days (long-term). Analyses of the transcriptome in the whole lung and the proteome in the bronchoalveolar lavage fluid of exposed animals were performed to understand the MWCNT underlying mechanisms of toxicity. Following inhalation of NM-401, we observed a dose-dependent increase in the number of differentially expressed genes and proteins, whereas there is no clear difference between the two concentrations of NM-403. After NM-403 inhalation, the number of differentially expressed genes and proteins varied less between the four post-exposure times compared to NM-401, which supports the postulation of a persistent effect of this type of CNT. Our toxicogenomics approaches give insights into the different toxicological profile following MWCNT exposure.


Assuntos
Exposição por Inalação/efeitos adversos , Pulmão/efeitos dos fármacos , Nanotubos de Carbono/toxicidade , Pneumonia/induzido quimicamente , Proteoma/metabolismo , Transcriptoma/efeitos dos fármacos , Administração por Inalação , Animais , Líquido da Lavagem Broncoalveolar/química , Feminino , Nanotubos de Carbono/química , Pneumonia/metabolismo , Ratos , Ratos Sprague-Dawley , Propriedades de Superfície , Toxicogenética
14.
J Occup Environ Hyg ; 18(2): 72-83, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33315526

RESUMO

Simple plastic face shields have numerous practical advantages over regular surgical masks. In light of the spreading COVID-19 pandemic, the potential of face shields as a substitution for surgical masks was investigated. In order to determine the efficacy of the protective equipment we used a cough simulator. The protective equipment considered was placed on a manikin head that simulated human breathing. Concentration and size distribution of small particles that reached the manikin respiration pathways during the few tens of seconds following the cough event were monitored. Additionally, water sensitive papers were taped on the tested protective equipment and the manikin face. In the case of frontal exposure, for droplet diameter larger than 3 µm, the shield efficiency in blocking cough droplets was found to be comparable to that of regular surgical masks, with enhanced protection for portions of the face that the mask does not cover. Additionally, for finer particles, down to 0.3 µm diameter, a shield blocked about 10 times more fine particles than the surgical mask. When exposure from the side was considered, the performance of the shield was found to depend dramatically on its geometry. While a narrow shield allowed more droplets and aerosol to penetrate in comparison to a mask under the same configuration, a slightly wider shield significantly improved the performance. The source control potential of shields was also investigated. A shield, and alternatively, a surgical mask, were placed on the cough simulator, while the breathing simulator, situated 60 cm away in the jet direction, remained totally exposed. In both cases, no droplets or particles were found in the vicinity of the breathing simulator. Conducted experiments were limited to short time periods after expiratory events, and do not include longer time ranges associated with exposure to suspended aerosol. Thus, additional evidence regarding the risk posed by floating aerosol is needed to establish practical conclusions regarding actual transmittance reduction potential of face shields and surgical face masks.


Assuntos
/prevenção & controle , Exposição por Inalação/análise , Máscaras/normas , Equipamento de Proteção Individual/normas , /isolamento & purificação , Aerossóis/análise , Microbiologia do Ar , Tosse/virologia , Monitoramento Ambiental , Humanos , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Exposição por Inalação/prevenção & controle , Teste de Materiais , Exposição Ocupacional/análise , Exposição Ocupacional/prevenção & controle
15.
Life Sci ; 267: 118912, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33338503

RESUMO

AIM: To explore the different consequences of acute and chronic exposure to chlorine gas (Cl2) on the functional and histological parameters of health mice. MAIN METHODS: Firstly, male BALB/c mice were acute exposed to 3.3 or 33.3 or 70.5 mg/m3 Cl2. We analyzed the lung function, the inflammatory cells in the bronchoalveolar lavage, cell influx in the peribrochoalveolar space and mucus production. In a second phase, mice were chronic exposed to 70.5 mg/m3 Cl2. Besides the first phase analyses, we also evaluated the epithelial cells thickness, collagen deposition in the airways, immunohistochemistry stain for IL-1ß, iNOS, IL-17 and ROCK-2 and the levels of IL-5, IL-13, IL-17, IL-1ß and TNF-α in lung homogenate. KEY FINDINGS: Acute exposure to chlorine impaired the lung function, increased the number of inflammatory cells in the BALF and in the airways, also increased the mucus production. Furthermore, when chlorine was exposed chronically, increased the airway remodeling with collagen deposition and epithelial cells thickness, positive cells for IL-1ß, iNOS, IL-17 in the airways and in the alveolar walls and ROCK-2 in the alveolar walls, lung inflammation with increased levels of IL-5, IL-13, IL-1ß and TNF-α in the lung homogenate, and also, induced the acid mucus production by the nasal epithelium. SIGNIFICANCE: Acute and chronic exposure to low dose of chlorine gas worsens lung function, induces oxidative stress activation and mucus production and contributes to augmenting inflammation in health mice.


Assuntos
Cloro/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Pneumonia/patologia , Células Epiteliais Alveolares/efeitos dos fármacos , Animais , Asma/patologia , Líquido da Lavagem Broncoalveolar/citologia , Cloro/metabolismo , Inflamação/patologia , Exposição por Inalação , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C
16.
Anesth Analg ; 132(1): 38-45, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33315602

RESUMO

BACKGROUND: Numerous barrier devices have recently been developed and rapidly deployed worldwide in an effort to protect health care workers (HCWs) from exposure to coronavirus disease 2019 (COVID-19) during high-risk procedures. However, only a few studies have examined their impact on the dispersion of droplets and aerosols, which are both thought to be significant contributors to the spread of COVID-19. METHODS: Two commonly used barrier devices, an intubation box and a clear plastic intubation sheet, were evaluated using a physiologically accurate cough simulator. Aerosols were modeled using a commercially available fog machine, and droplets were modeled with fluorescein dye. Both particles were propelled by the cough simulator in a simulated intubation environment. Data were captured by high-speed flash photography, and aerosol and droplet dispersion were assessed qualitatively with and without a barrier in place. RESULTS: Droplet contamination after a simulated cough was seemingly contained by both barrier devices. Simulated aerosol escaped the barriers and flowed toward the head of the bed. During barrier removal, simulated aerosol trapped underneath was released and propelled toward the HCW at the head of the bed. Usage of the intubation sheet concentrated droplets onto a smaller area. If no barrier was used, positioning the patient in slight reverse Trendelenburg directed aerosols away from the HCW located at the head of the bed. CONCLUSIONS: Our observations imply that intubation boxes and sheets may reduce HCW exposure to droplets, but they both may merely redirect aerosolized particles, potentially resulting in increased exposure to aerosols in certain circumstances. Aerosols may remain within the barrier device after a cough, and manipulation of the box may release them. Patients should be positioned to facilitate intubation, but slight reverse Trendelenburg may direct infectious aerosols away from the HCW. Novel barrier devices should be used with caution, and further validation studies are necessary.


Assuntos
/terapia , Controle de Infecções/instrumentação , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Exposição por Inalação/prevenção & controle , Intubação Intratraqueal , Exposição Ocupacional/prevenção & controle , Equipamento de Proteção Individual , Aerossóis , Humanos , Exposição por Inalação/efeitos adversos , Intubação Intratraqueal/efeitos adversos , Manequins , Teste de Materiais , Exposição Ocupacional/efeitos adversos , Saúde do Trabalhador
17.
Allergol. immunopatol ; 48(6): 745-752, nov.-dic. 2020. graf
Artigo em Inglês | IBECS | ID: ibc-199266

RESUMO

Asthma and other inhaled allergies are some of the most common paediatric diseases. The association of exposure to allergens with induction and exacerbation of symptoms has been proven. The majority of allergens are permanently or periodically suspended in the air, which leads to impaired quality of life for sensitive patients. Therefore, many methods of prevention and therapy of allergic diseases have been developed. The method of allergen exposure avoidance is often the first and the most significant measure. The present research has been conducted to evaluate, based on scientific data, which measures have the most reliable evidence of effectiveness. Environmental allergen avoidance methods, despite limited evidence supporting their clinical efficacy, are listed as the main therapeutic approaches in most recommendations. The significance of the holistic approach is also emphasised: only simultaneous introduction of several avoidance methods can bring possibly beneficial effects for the patient


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Assuntos
Humanos , Asma/prevenção & controle , Rinite Alérgica/prevenção & controle , Exposição por Inalação/prevenção & controle , Alérgenos/efeitos adversos , Asma/etiologia , Rinite Alérgica/etiologia , Exposição por Inalação/efeitos adversos , Antígenos de Dermatophagoides/efeitos adversos , Pelo Animal , Pólen/efeitos adversos , Fungos , Baratas , Fatores de Risco
18.
PLoS One ; 15(12): e0243826, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33370308

RESUMO

PURPOSE: Recent studies suggest that occupational inhalant exposures trigger exacerbations of asthma and chronic obstructive pulmonary disease, but findings are conflicting. METHODS: We included 7,768 individuals with self-reported asthma (n = 3,215) and/or spirometric airflow limitation (forced expiratory volume in 1 second (FEV1)/ forced expiratory volume (FVC) <0.70) (n = 5,275) who participated in The Copenhagen City Heart Study or The Copenhagen General Population Study from 2001-2016. Occupational exposure was assigned by linking job codes with job exposure matrices, and exacerbations were defined by register data on oral corticosteroid treatment, emergency care unit assessment or hospital admission. Associations between occupational inhalant exposure each year of follow-up and exacerbation were assessed by Cox regression with time varying exposure and age as the underlying time scale. RESULTS: Participants were followed for a median of 4.6 years (interquartile range, IQR 5.4), during which 870 exacerbations occurred. Exacerbations were not associated with any of the selected exposures (high molecular weight sensitizers, low molecular weight sensitizers, irritants or low and high levels of mineral dust, biological dust, gases & fumes or the composite variable vapours, gases, dusts or fumes). Hazards ratios ranged from 0.8 (95% confidence interval: 0.7;1.0) to 1.2 (95% confidence interval: 0.9;1.7). CONCLUSION: Exacerbations of obstructive airway disease were not associated with occupational inhalant exposures assigned by a job exposure matrix. Further studies with alternative exposure assessment are warranted.


Assuntos
Asma/epidemiologia , Asma/patologia , Progressão da Doença , Exposição Ocupacional/efeitos adversos , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/patologia , Feminino , Humanos , Exposição por Inalação , Masculino , Pessoa de Meia-Idade
19.
J Acoust Soc Am ; 148(4): 2322, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33138475

RESUMO

Respiratory droplets emitted during speech can transmit oral bacteria and infectious viruses to others, including COVID-19. Loud speech can generate significantly higher numbers of potentially infectious respiratory droplets. This study assessed the effect of speech volume on respiratory emission of oral bacteria as an indicator of potential pathogen transmission risk. Loud speech (average 83 dBA, peak 94 dBA) caused significantly higher emission of oral bacteria (p = 0.004 compared to no speech) within 1 ft from the speaker. N99 respirators and simple cloth masks both significantly reduced emission of oral bacteria. This study demonstrates that loud speech without face coverings increases emission of respiratory droplets that carry oral bacteria and may also carry other pathogens such as COVID-19.


Assuntos
Microbiologia do Ar , Bactérias/patogenicidade , Infecções Bacterianas/transmissão , Exposição por Inalação , Boca/microbiologia , Respiração , Acústica da Fala , Aerossóis , Infecções Bacterianas/microbiologia , Infecções Bacterianas/prevenção & controle , Humanos , Exposição por Inalação/prevenção & controle , Máscaras , Equipamento de Proteção Individual , Dispositivos de Proteção Respiratória
20.
J Acoust Soc Am ; 148(4): 2096, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33138536

RESUMO

Brass wind instruments with long sections of cylindrical pipe, such as trumpets and trombones, sound "brassy" when played at a fortissimo level due to the generation of a shock front in the instrument. It has been suggested that these shock fronts may increase the spread of COVID-19 by propelling respiratory particles containing the SARS-CoV-2 virus several meters due to particle entrainment in the low pressure area behind the shocks. To determine the likelihood of this occurring, fluorescent particles, ranging in size from 10-50 µm, were dropped into the shock regions produced by a trombone, a trumpet, and a shock tube. Preliminary results indicate that propagation of small airborne particles by the shock fronts radiating from brass wind instruments is unlikely.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/transmissão , Exposição por Inalação/prevenção & controle , Música , Pneumonia Viral/transmissão , Isolamento Social , Aerossóis , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/virologia , Desenho de Equipamento , Interações Hospedeiro-Patógeno , Humanos , Movimento (Física) , Pandemias/prevenção & controle , Tamanho da Partícula , Pneumonia Viral/prevenção & controle , Pneumonia Viral/virologia
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