Characterization of indoor air quality and efficiency of air purifier in childcare centers, Korea
TL;DR: In this article, the average indoor concentrations of fine particles less than 2.5μm were collected from inside ten childcare centers, and from their adjacent outdoor environments in Seoul, Korea during the summer, autumn and winter seasons.
About: This article is published in Building and Environment.The article was published on 2014-12-01. It has received 75 citations till now. The article focuses on the topics: Air purifier & Indoor air quality.
Citations
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TL;DR: In this article, a review of the impact of PM2.5 in indoor urban environments summarizes existing research in this area, specifically, the main sources and sinks in outdoor and indoor environments, the exposure limits that are currently applicable throughout the world, and the main socioeconomic impacts of exposure to PM 2.5.
154 citations
TL;DR: This study will help policy makers to better understand the patterns of the public's perception of environmental problems and consequently improve the government's capability to deal with these challenges.
68 citations
TL;DR: The study revealed that the use of air purifiers with windows kept closed (natural ventilation) can lead to a significant reduction in terms of indoor-to-outdoor concentration ratios, and for low ACH values, the reduction is quite negligible.
62 citations
TL;DR: Wang et al. as mentioned in this paper investigated the effects of infiltration and indoor pollution on the level of PM2.5 in residential buildings, using a DustTrak II aerosol monitor, measuring in a typical residential building in Tianjin with different openings to the external environment.
Abstract: Severe haze weather in recent times in China has drawn global attention and growing public concern over implications to people's health. This study aims to investigate the effects of infiltration and indoor pollution on the level of PM2.5 concentrations in residential buildings. Using a DustTrak II aerosol monitor, PM2.5 concentrations were measured in a typical residential building in Tianjin with different openings to the external environment. When the openings had a void of 10 mm, indoor PM2.5 concentration was similar to that of outdoor. When the indoor PM2.5 concentration reached its peak, the Indoor-to-Outdoor ratio (I/O) was 0.67–0.89 with a delay compared to the outdoor PM2.5 concentration. Higher outdoor wind speeds were associated with higher I/O ratios. With well-sealed windows and doors, PM2.5 concentrations decreased irrespective of the changes occurring outdoor with a decay rate of 0.002 min−1. With regard to the effects of indoor pollution, smoking could make the indoor PM2.5 concentrations rise rapidly to a level of 1280 μg m−3. Kitchen PM2.5 concentrations rose while cooking up to 3000 μg m−3, which largely depended on the method of cooking. Kitchen ventilator was able to control the pollution fairly quickly and reduce the impact on adjacent spaces. Other human activities such as walking, dressing, and sweeping were responsible for an increase in PM2.5 concentration by almost 33%.
57 citations
TL;DR: Negative associations between asthma and FEV1/FVC ratio, and between respiratory symptom score (RSS) and FEVs, support the idea that the PF test can be a good indicator for (early) prognosis of respiratory diseases.
57 citations
References
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TL;DR: Fine particulate and sulfur oxide--related pollution were associated with all-cause, lung cancer, and cardiopulmonary mortality and long-term exposure to combustion-related fine particulate air pollution is an important environmental risk factor for cardiopULmonary and lung cancer mortality.
Abstract: ContextAssociations have been found between day-to-day particulate air pollution
and increased risk of various adverse health outcomes, including cardiopulmonary
mortality. However, studies of health effects of long-term particulate air
pollution have been less conclusive.ObjectiveTo assess the relationship between long-term exposure to fine particulate
air pollution and all-cause, lung cancer, and cardiopulmonary mortality.Design, Setting, and ParticipantsVital status and cause of death data were collected by the American
Cancer Society as part of the Cancer Prevention II study, an ongoing prospective
mortality study, which enrolled approximately 1.2 million adults in 1982.
Participants completed a questionnaire detailing individual risk factor data
(age, sex, race, weight, height, smoking history, education, marital status,
diet, alcohol consumption, and occupational exposures). The risk factor data
for approximately 500 000 adults were linked with air pollution data
for metropolitan areas throughout the United States and combined with vital
status and cause of death data through December 31, 1998.Main Outcome MeasureAll-cause, lung cancer, and cardiopulmonary mortality.ResultsFine particulate and sulfur oxide–related pollution were associated
with all-cause, lung cancer, and cardiopulmonary mortality. Each 10-µg/m3 elevation in fine particulate air pollution was associated with approximately
a 4%, 6%, and 8% increased risk of all-cause, cardiopulmonary, and lung cancer
mortality, respectively. Measures of coarse particle fraction and total suspended
particles were not consistently associated with mortality.ConclusionLong-term exposure to combustion-related fine particulate air pollution
is an important environmental risk factor for cardiopulmonary and lung cancer
mortality.
7,803 citations
Journal Article•
TL;DR: The variation in the prevalences of asthma, allergic rhinoconjunctivitis, and atopic-eczema symptoms is striking between different centres throughout the world and will form the basis of further studies to investigate factors that potentially lead to these international patterns.
3,584 citations
TL;DR: The number of people exposed to environmental tobacco smoke in California seems to have decreased over the same time period, where exposure is determined by the reported time spent with a smoker.
Abstract: Because human activities impact the timing, location, and degree of pollutant exposure, they play a key role in explaining exposure variation. This fact has motivated the collection of activity pattern data for their specific use in exposure assessments. The largest of these recent efforts is the National Human Activity Pattern Survey (NHAPS), a 2-year probability-based telephone survey ( n=9386) of exposure-related human activities in the United States (U.S.) sponsored by the U.S. Environmental Protection Agency (EPA). The primary purpose of NHAPS was to provide comprehensive and current exposure information over broad geographical and temporal scales, particularly for use in probabilistic population exposure models. NHAPS was conducted on a virtually daily basis from late September 1992 through September 1994 by the University of Maryland's Survey Research Center using a computer-assisted telephone interview instrument (CATI) to collect 24-h retrospective diaries and answers to a number of personal and exposure-related questions from each respondent. The resulting diary records contain beginning and ending times for each distinct combination of location and activity occurring on the diary day (i.e., each microenvironment). Between 340 and 1713 respondents of all ages were interviewed in each of the 10 EPA regions across the 48 contiguous states. Interviews were completed in 63% of the households contacted. NHAPS respondents reported spending an average of 87% of their time in enclosed buildings and about 6% of their time in enclosed vehicles. These proportions are fairly constant across the various regions of the U.S. and Canada and for the California population between the late 1980s, when the California Air Resources Board (CARB) sponsored a state-wide activity pattern study, and the mid-1990s, when NHAPS was conducted. However, the number of people exposed to environmental tobacco smoke (ETS) in California seems to have decreased over the same time period, where exposure is determined by the reported time spent with a smoker. In both California and the entire nation, the most time spent exposed to ETS was reported to take place in residential locations.
3,400 citations
"Characterization of indoor air qual..." refers background in this paper
...Particulate matter (PM) concentrations indoors are about six times higher than outdoors [4,5]....
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TL;DR: In this article, the authors investigated worldwide prevalence of asthma, allergic rhinoconjunctivitis, and atopic disorders in children, and found differences of between 20-fold and 60-fold between centres in the prevalence of symptoms of asthma.
3,019 citations
TL;DR: A classification system in which phylogenetically neighboring taxa at the genus level are clustered into families, suborders, orders, subclasses, and a class irrespective of those phenotypec characteristics on which the delineation of taxa has been based in the past is presented.
Abstract: A new hierarchic classification structure for the taxa between the taxonomic levels of genus and class is Proposed for the actinomycete line of descent as defined by analysis of small subunit (16S) rRNA and genes coding for this molecule (rDNA). While the traditional circumscription of a genus of the actinomycete subphylum is by and large in accord with the 16S rRNA/rDNA-based phylogenetic clustering of these organisms. most of the higher taxa proposed in the past do not take into account the phylogenetic clustering of genera. The rich chemical, morphological and physiological diversity of phylogenetically closely related genera makes the description of families and higher taxa so broad that they become meaningless for the description of the enclosed taxa. Here we present a classification system in which phylogenetically neighboring taxa at the genus level are clustered into families, suborders, orders, subclasses, and a class irrespective of those phenotypec characteristics on which the delineation of taxa has been based in the past. Rather than being based on a listing of a wide array of chemotaxonomic, morphological, and physiological properties, the delineation is based solely on 16S rDNA/rRNA sequence-based phylogenetic clustering and the presence of taxon-specific 16S rDNA RNA signature nucleotides.
1,597 citations
"Characterization of indoor air qual..." refers background or methods in this paper
...According to modern taxonomy based on genetic sequencing, they can cause hypersensitivity pneumonitis, and belong to the larger class of Actinobacteria such as Actinomycetes, Micrococcus and Staphylococcus, which inhabit the skin and dandruff [51]....
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...The counts for air sample plates were corrected for multiple impactions using the positive hole conversion method, and reported as colony-forming units per cubic meter of air (CFU/m3) [51]....
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...Furthermore, sample handling and storage, as well as the analysis of the collected biological particles, are considerably different from the procedures used in general particle sampling [51]....
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...2 mm in the outdoor air, approximately 5e50% appeared to be of biological origin [51]....
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...They may be carried by other particles, such as water droplet residues, plant materials, or the skin fragments of animals [35,51]....
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