986 resultados para Air Particulate Matter


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Thesis (Master's)--University of Washington, 2016-06

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Thesis (Ph.D.)--University of Washington, 2016-06

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Thesis (Master's)--University of Washington, 2016-06

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Regular aerobic exercise is recommended by physicians to improve health and longevity. However, individuals exercising in urban regions are often in contact with air pollution, which includes particles and gases associated with respiratory disease and cancer. We describe the recent evidence on the cardiovascular effects of air pollution, and the implications of exercising in polluted environments, with a view to informing clinicians and other health professionals. There is now strong evidence that fine and ultra fine particulate matter present in air pollution increases cardiovascular morbidity and mortality. The main mechanisms of disease appear to be related to an increase in the pathogenic processes associated with atherosclerosis. People exercising in environments pervaded by air contaminants are probably at increased risk, due to an exercise-induced amplification in respiratory uptake, lung deposition and toxicity of inhaled pollutants. We make evidence-based recommendations for minimizing exposure to air-borne toxins while exercising, and suggest that this advice be passed on to patients where appropriate.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Background: persons who are 65 years or older often spend an important part of their lives indoors thus adverse indoor climate might influence their health status. Objective: to evaluate the influence of indoor air quality and contaminants on older people’s respiratory health. Design: cross-sectional study. Setting: 21 long-term care residences (LTC) in the city of Porto, Portugal. Subjects: older people living in LTC with ≥65 years old. Methods: the Portuguese version of BOLD questionnaire was administered by an interviewer to older residents able to participate (n = 143). Indoor air contaminants (IAC) were measured twice, during winter and summer in 135 areas. Mixed effects logistic regression models were used to study the association between the health questionnaire results and the monitored IAC, adjusted for age, smoking habits, gender and number of years living in the LTC. Results: cough (23%) and sputum (12%) were the major respiratory symptoms, and allergic rhinitis (18%) the main selfreported illness. Overall particulate matter up to 2.5 micrometres in size median concentration was above the reference levels both in winter and summer seasons. Peak values of particulate matter up to 10 micrometres in size (PM10), total volatile organic compounds, carbon dioxide, bacteria and fungi exceeded the reference levels. Older people exposed to PM10 above the reference levels demonstrated higher odds of allergic rhinitis (OR = 2.9, 95% CI: 1.1–7.2). Conclusion: high levels of PM10 were associated with 3-fold odds of allergic rhinitis. No association was found between indoor air chemical and biological contaminants and respiratory symptoms.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Indoor air quality (IAQ) parameters in 73 primary classrooms in Porto were examined for the purpose of assessing levels of volatile organic compounds (VOCs), aldehydes, particulate matter, ventilation rates and bioaerosols within and between schools, and potential sources. Levels of VOCs, aldehydes, PM2.5 , PM10 , bacteria and fungi, carbon dioxide (CO2 ), carbon monoxide, temperature and relative humidity were measured indoors and outdoors and a walkthrough survey was performed concurrently. Ventilation rates were derived from CO2 and occupancy data. Concentrations of CO2 exceeding 1000 ppm were often encountered, indicating poor ventilation. Most VOCs had low concentrations (median of individual species <5 μg/m(3) ) and were below the respective WHO guidelines. Concentrations of particulate matter and culturable bacteria were frequently higher than guidelines/reference values. The variability of VOCs, aldehydes, bioaerosol concentrations, and CO2 levels between schools exceeded the variability within schools. These findings indicate that IAQ problems may persist in classrooms where pollutant sources exist and classrooms are poorly ventilated; source control strategies (related to building location, occupant behavior, maintenance/cleaning activities) are deemed to be the most reliable for the prevention of adverse health consequences in children in schools.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A cross-sectional survey was conducted to characterize the indoor air quality (IAQ) in schools and its relationship with children's respiratory symptoms. Concentrations of volatile organic compounds (VOC), aldehydes, PM2.5, PM10, carbon dioxide, bacteria and fungi were assessed in 73 classrooms from 20 public primary schools located in Porto, Portugal. Children who attended the selected classrooms (n = 1134) were evaluated by a standardised health questionnaire completed by the legal guardians; spirometry and exhaled nitric oxide tests. The results indicated that no classrooms presented individual VOC pollutant concentrations higher than the WHO IAQ guidelines or by INDEX recommendations; while PM2.5, PM10 and bacteria levels exceeded the WHO air quality guidelines or national limit values. High levels of total VOC, acetaldehyde, PM2.5 and PM10 were associated with higher odds of wheezing in children. Thus, indoor air pollutants, some even at low exposure levels, were related with the development of respiratory symptoms. The results pointed out that it is crucial to take into account the unique characteristics of the public primary schools, to develop appropriate control strategies in order to reduce the exposure to indoor air pollutants and, therefore, to minimize the adverse health effects.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The main aim of the research project "On the Contribution of Schools to Children's Overall Indoor Air Exposure" is to study associations between adverse health effects, namely, allergy, asthma, and respiratory symptoms, and indoor air pollutants to which children are exposed to in primary schools and homes. Specifically, this investigation reports on the design of the study and methods used for data collection within the research project and discusses factors that need to be considered when designing such a study. Further, preliminary findings concerning descriptors of selected characteristics in schools and homes, the study population, and clinical examination are presented. The research project was designed in two phases. In the first phase, 20 public primary schools were selected and a detailed inspection and indoor air quality (IAQ) measurements including volatile organic compounds (VOC), aldehydes, particulate matter (PM2.5, PM10), carbon dioxide (CO2), carbon monoxide (CO), bacteria, fungi, temperature, and relative humidity were conducted. A questionnaire survey of 1600 children of ages 8-9 years was undertaken and a lung function test, exhaled nitric oxide (eNO), and tear film stability testing were performed. The questionnaire focused on children's health and on the environment in their school and homes. One thousand and ninety-nine questionnaires were returned. In the second phase, a subsample of 68 children was enrolled for further studies, including a walk-through inspection and checklist and an extensive set of IAQ measurements in their homes. The acquired data are relevant to assess children's environmental exposures and health status.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Twenty one sampling locations were assessed for carbon monoxide (CO), carbondioxide (CO2), oxygen (O2), sulphur dioxide (SO2), nitrogen dioxide (NO2), nitrogen oxide (NO), suspended particulate matter (SPM) and noise level using air pollutants measurement methods approved by ASTM for each specific parameter. All equipments and meters were all properly pre-calibrated before each usage for quality assurance. Findings of the study showed that measured levels of noise (61.4 - 101.4 dBA), NO (0.0 - 3.0 ppm), NO2 (0.0 - 3.0 ppm), CO (1.0 – 42.0 ppm) and SPM (0.14 – 4.82 ppm) in all sampling areas were quite high and above regulatory limits however there was no significant difference except in SPM (at all the sampling points), and noise, NO2 and NO (only in major traffic intersection). Air quality index (AQI) indicates that the ambient air can be described as poor for SPM, varied from good to very poor for CO, while NO and NO2 are very good except at major traffic intersection where they were both poor and very poor (D-E). The results suggest that strict and appropriate vehicle emission management, industrial air pollution control coupled with close burning management of wastes should be considered in the study area to reduce the risks associated with these pollutants.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

The practice of burning sugarcane obtained by non-mechanized harvesting exposes workers and the people of neighboring towns to high concentrations of particulate matter (PM) that is harmful to health, and may trigger a series of cardiorespiratory diseases. The aim of this study was to analyze the chemical composition of the micro-particles coming from sugarcane burning residues and to verify the effects of this micro-particulate matter on lung and tracheal tissues. Micro-particulate matter (PM10) was obtained by dissolving filter paper containing burnt residues in NaCl solution. This material was instilled into the Wistar rats' nostrils. Histological analyses (hematoxylin and eosin - HE) of cardiac, lung and tracheal tissues were performed. Inflammatory mediators were measured in lung tissues by using ELISA. The chemical composition of the particulate material revealed a large quantity of the phthalic acid ester, high concentrations of phenolic compounds, anthracene and polycyclic aromatic hydrocarbons (PAH). Histological analysis showed a reduction in subjacent conjunctive tissue in the trachea, lung inflammation with inflammatory infiltrate formation and reduction of alveolar spaces and a significant increase (p<0.05) in the release of IL-1α, IL-1β, IL-6, and INF-γ in the group treated with PM10 when compared to the control group. We concluded that the burning sugarcane residues release many particles, which have toxic chemical compounds. The micro-particulate matter can induce alterations in the respiratory system.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

Ozone and inhalable particulate matter are the major air pollutants in the Metropolitan Area of São Paulo, Brazil, a region that has more than 19 million inhabitants and approximately 7 million registered vehicles. Proximity of roadways, adjacent land use, and local circulation are just some of the factors that can affect the results of monitoring of pollutant concentrations. The so-called weekend effect (higher ozone concentrations on weekends than on weekdays) might be related to the fact that concentrations of ozone precursors, such as nitrogen oxides (NOx) and Non Methane-Hydrocarbon (NMHC), are relatively lower on weekends. This phenomenon has been reported in some areas of the United States since the 1970s. The differences between the concentrations of ozone in period of weekend and weekday, were obtained from analysis of data hourly average of CETESB for 2004, studied the precursors to the formation of troposphere ozone, the meteorological variables and traffic profile for RMSP. Because of the proximity to sources of emissions from the station Pinheiros showed higher concentrations of NO and NO² and greater variations to the periods weekend and weekday. With fewer vehicles circulating during the weekend, and consequently less emission of pollutants, it has cleaner air and less concentration of NO and NO², there is the ideal setting to the formation of troposphere ozone, despite the lower concentration of NO². The proximity with the source emissions, aided by the increased availability of solar radiation and the presence of ozone precursors, were factors conditions for the occurrence of weekend effect.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

OBJETIVO: Estimar a prevalência de sintomas respiratórios e analisar fatores associados, bem como medidas de pico de fluxo expiratório em escolares. MÉTODOS: Estudo descritivo transversal com escolares de dez a 14 anos de Monte Aprazível, SP. Foram aplicados questionários sobre sintomas de asma e de rinite do protocolo International Study of Asthma and Allergies in Childhood, questões sociodemográficas, fatores predisponentes e antecedentes pessoais e familiares. Foram realizadas medidas repetidas do pico de fluxo expiratório nas crianças e dos níveis de concentração de material particulado (MP2,5) e de black carbon. RESULTADOS: A prevalência de sintomas de asma foi de 11% e de 33,2% de rinite; 10,6% apresentaram mais de quatro crises de sibilos nos últimos 12 meses. Antecedentes familiares para bronquite e rinite associaram-se à presença de asma (p = 0,002 e p < 0,001) e de rinite atuais (p < 0,001 e p < 0,001, respectivamente). Para rinite, houve associação com presença de mofo ou rachadura na casa (p = 0,009). Houve maior freqüência de rinite nos meses de junho a outubro, período de safra da cana de açúcar. Prevalência diária de pico de fluxo expiratório abaixo de 20% da mediana de medidas na criança foi maior em dias com maior concentração de MP2,5. CONCLUSÕES: A prevalência de sintomas de asma está abaixo e a de rinite está acima da média nacional. Ainda que dentro dos níveis aceitáveis, a poluição nos períodos de queima da palha da cana-de-açúcar pode contribuir para a exacerbação de episódios de asma e de rinite.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

Background: The Brazilian Amazon has suffered impacts from non-sustainable economic development, especially owing to the expansion of agricultural commodities into forest areas. The Tangara da Serra region, located in the southern of the Legal Amazon, is characterized by non-mechanized sugar cane production. In addition, it lies on the dispersion path of the pollution plume generated by biomass burning. The aim of this study was to assess the genotoxic potential of the atmosphere in the Tangara da Serra region, using Tradescantia pallida as in situ bioindicator. Methods: The study was conducted during the dry and rainy seasons, where the plants were exposed to two types of exposure, active and passive. Results: The results showed that in all the sampling seasons, irrespective of exposure type, there was an increase in micronucleus frequency, compared to control and that it was statistically significant in the dry season. A strong and significant relationship was also observed between the increase in micronucleus incidence and the rise in fine particulate matter, and hospital morbidity from respiratory diseases in children. Conclusions: Based on the results, we demonstrated that pollutants generated by biomass burning in the Brazilian Amazon can induce genetic damage in test plants that was more prominent during dry season, and correlated with the level of particulates and elevated respiratory morbidity.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

Lignin phenols were measured in the sediments of Sepitiba Bay, Rio de Janeiro, Brazil and in bedload sediments and suspended sediments of the four major fluvial inputs to the bay: Sao Francisco and Guandu Channels and the Guarda and Cacao Rivers. Fluvial suspended lignin yields (Sigma 8 3.5-14.6 mgC 10 g dw(-1)) vary little between the wet and dry seasons and are poorly correlated with fluvial chlorophyll concentrations (0.8-50.2 mu gC L(-1)). Despite current land use practices that favor grassland agriculture or industrial uses, fluvial lignin compositions are dominated by a degraded leaf-sourced material. The exception is the Guarda River, which has a slight influence from grasses. The Lignin Phenol Vegetation Index, coupled with acid/aldehyde and 3.5 Db/V ratios, indicate that degraded leaf-derived phenols are also the primary preserved lignin component in the bay. The presence of fringe Typha sp. and Spartina sp. grass beds surrounding portions of the Bay are not reflected in the lignin signature. Instead, lignin entering the bay appears to reflect the erosion of soils containing a degraded signature from the former Atlantic rain forest that once dominated the watershed, instead of containing a significant signature derived from current agricultural uses. A three-component mixing model using the LPVI, atomic N:C ratios, and stable carbon isotopes (which range between -26.8 and -21.8 parts per thousand) supports the hypothesis that fluvial inputs to the bay are dominated by planktonic matter (78% of the input), with lignin dominated by leaf (14% of the input) over grass (6%). Sediments are composed of a roughly 50-50 mixture of autochthonous material and terrigenous material, with lignin being primarily sourced from leaf. (C) 2010 Elsevier Ltd. All rights reserved.