scholarly journals Diversity of yeast-like fungi and their selected properties in bioaerosol premises utility

2014 ◽  
Vol 49 (1) ◽  
pp. 23-30
Author(s):  
Elżbieta Ejdys ◽  
Maria Dynowska ◽  
Anna Biedunkiewicz ◽  
Ewa Sucharzewska
Keyword(s):  
Indoor Air ◽  
Inorganic Compounds ◽  
School Buildings ◽  
Specific Substrate ◽  
Carotenoid Pigments ◽  
Building Structures ◽  
Outdoor Air ◽  
Heating Season ◽  
Physiological Characters ◽  
Indoor And Outdoor

A total of 69 isolates of yeasts were recorded in the indoor air of the school buildings: 43 in heated rooms and 26 in unheated rooms. Perfect stages prevailed. Fungi isolated in our study belonged to 39 species. These were mostly monospecific isolates although five two-species isolates were noted. Differences in the properties of physiological characters of fungi isolated in both study seasons were observed. As indoor and outdoor air does not mix during the heating season, a specific substrate for prototrophic, non-fermenting yeastlike fungi forms. Acid production allows fungi to dissolve inorganic compounds in building structures and to release needed microcomponents. Abilities to produce carotenoid pigments are clearly promoted in yeast-like fungi living indoor. This may be related to the accumulation of compounds that are indirect stages in the cycle of biosynthesis of carotenoids or a surplus of oxidizing compounds.

Characterization of Bacteria and Fungi Bioaerosol in the Indoor Air of selected Primary Schools in Malaysia

2011 ◽  
Vol 20 (6) ◽  
pp. 607-617 ◽  
Author(s):  
Nor Husna Mat Hussin ◽  
Lye Munn Sann ◽  
Mariana Nor Shamsudin ◽  
Zailina Hashim
Keyword(s):  
Indoor Air ◽  
Primary Schools ◽  
Average Concentration ◽  
Outdoor Air ◽  
Inadequate Ventilation ◽  
Bacillus Spp ◽  
Bacteria And Fungi ◽  
Staphylococcus Spp ◽  
Indoor And Outdoor

This study reports the types and concentrations of bacterial and fungal bioaerosols found in five randomly selected primary schools in Malaysia. Normal flora bacteria was the most frequently isolated bacteria including Staphylococcus spp., Pseudomonas spp. and Bacillus spp. Terribacillus spp. found in this study had never been reported before. The most frequently isolated fungal genera were Aspergillus, Penicillium, Fusarium, Rhizopus and Zygomycetes. The average concentration of bacteria in indoor and outdoor air were 1025 ± 612 CFU/m3 and 1473 ± 1261 CFU/m3, respectively, while the average concentration of fungal bioaerosol in indoor and outdoor air were 292 ± 83 CFU/m3 and 401 ± 235 CFU/m3, respectively. The percentages of bacterial and fungal samples that were within the American Conference of Industrial Hygenists (ACGIH) recommended levels were 44% and 33.8%, respectively. The ratio of indoor to outdoor fungi concentration was below 1.0, suggesting minimal indoor generative source for fungal bioaerosols. However, the ratio of indoor to outdoor bacteria concentration was approaching 1.0, suggesting the presence of potential internal generative source and inadequate ventilation. Building occupants might be one of the potential sources of bacteria in the indoor air as the bacteria concentrations without occupants were significantly lower than with occupants (p < 0.05).

scholarly journals Yeast-like fungi isolated from indoor air in school buildings and the surrounding outdoor air

2013 ◽  
Vol 44 (1) ◽  
pp. 97-107 ◽  
Author(s):  
Elżbieta Ejdys ◽  
Joanna Michalak ◽  
Katarzyna M. Szewczyk
Keyword(s):  
Yarrowia Lipolytica ◽  
Indoor Air ◽  
Kluyveromyces Marxianus ◽  
Abiotic Factors ◽  
Kluyveromyces Lactis ◽  
School Buildings ◽  
Outdoor Air ◽  
Limited Access ◽  
Phenological Changes ◽  
Epidemiological Risk

A total of 111 isolates of yeast-like fungi and yeasts belonging to 40 species of 19 genera were identified in indoor air and outdoor air. Only one species, <em>Kluyveromyces marxianus</em>, was recorded in both types of air and seasons (spring and autumn). <em>Kluyveromyces lactis</em> and <em>Yarrowia lipolytica</em>, a species having the greatest symbiotic abilities, dominated in indoor air and outdoor air, respectively. Intensely used rooms, especially those with limited access of air, have the broadest range of species of yeast-like fungi. A comparison of both habitats shows that school rooms pose a greater epidemiological risk of yeast-like infections than outdoor air. The indoor as well as outdoor mycobiota undergoes phenological changes although it is determined by other biotic and abiotic factors.

scholarly journals Winter Thermal Comfort and Perceived Air Quality: A Case Study of Primary Schools in Severe Cold Regions in China

Energies ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5958
Author(s):  
Fusheng Ma ◽  
Changhong Zhan ◽  
Xiaoyang Xu ◽  
Guanghao Li
Keyword(s):  
Air Quality ◽  
Primary School ◽  
Thermal Comfort ◽  
Indoor Air ◽  
Primary Schools ◽  
Natural Ventilation ◽  
Thermal Sensation ◽  
School Buildings ◽  
Heating Season ◽  
Cold Regions

In Northeast China, most classrooms in primary and secondary schools still use natural ventilation during cold days in winter. This study investigated the thermal comfort and the perceived air quality of children in primary schools in severe cold regions in China. Field measurements were conducted in four typical primary classrooms in two naturally ventilated teaching buildings in the winter of 2016 in the provincial city of Shenyang. Six field surveys were distributed to 141 primary students aged 8 to 11, and 835 valid questionnaires were collected. The results showed that the indoor temperature and the daily mean CO2 concentrations of the primary school classrooms ranged from 17.06 to 24.29 °C and from 1701 to 3959 ppm, respectively. The thermal neutral temperature of the primary school students was 18.5 °C, and the 90% thermal comfort temperature ranged from 17.3 to 20.1 °C. Children were able to respond to changes in indoor air quality, but there was no significant correlation between the children’s perceptions of air quality and the carbon dioxide levels in the classroom. In general, children have a lower comfort temperature than adults. In addition, children are more sensitive to temperature changes during the heating season than adults. Due to differences in thermal sensation between children and adults, the current thermal comfort standard based on adult data is not applicable to primary school buildings and children. The air quality evaluation during heating season indicates that it is necessary to add indoor air environment monitoring instruments and purification equipment to the naturally ventilated classrooms. At present and in the future, more research based on children’s data is needed to solve the indoor air environment problems in primary school buildings.

scholarly journals Indoor Air Quality Investigation at Primary Classrooms in Hamirpur, Himachal Pradesh, India

2019 ◽  
Vol 24 ◽  
pp. 45-48 ◽  
Author(s):  
Venu Shree ◽  
Bhanu M. Marwaha ◽  
Pamita Awasthi
Keyword(s):  
Air Quality ◽  
Relative Humidity ◽  
Indoor Air ◽  
Himachal Pradesh ◽  
Building Performance ◽  
Outdoor Air ◽  
Primary Classrooms ◽  
Outdoor Air Quality ◽  
Hybrid Ventilation ◽  
Indoor And Outdoor

Two schools in Hamirpur (Himachal Pradesh, India) having hybrid ventilation (ceiling fan) were selected for indoor and outdoor air quality investigation. Investigated parameters include temperature, relative humidity, CO2, and PM2.5 for both indoor and outdoor air quality. The average concentrations of CO2, and PM2.5 are estimated for indoor and outdoor air quality. Result shows that adopted building performance is not good in comparison with designed ones. The indoor concentrations of various pollutants are found to be higher in comparison with outdoor, so there is an urgent need to reduce the levels of pollutants inside the primary classrooms.

scholarly journals Determination of Lead, Cations, and Anions Concentration in Indoor and Outdoor Air at the Primary Schools in Kuala Lumpur

2014 ◽  
Vol 2014 ◽  
pp. 1-3 ◽  
Author(s):  
Normah Awang ◽  
Farhana Jamaluddin
Keyword(s):  
Indoor Air ◽  
Primary Schools ◽  
Motor Vehicles ◽  
Kuala Lumpur ◽  
Outdoor Air ◽  
Congested Traffic ◽  
Suspended Particulates ◽  
Vehicles Emissions ◽  
Indoor And Outdoor

This study was carried out to determine the concentration of lead (Pb), anions, and cations at six primary schools located around Kuala Lumpur. Low volume sampler (MiniVolPM10) was used to collect the suspended particulates in indoor and outdoor air. Results showed that the concentration of Pb in indoor air was in the range of 5.18 ± 1.08 μg/g–7.01 ± 0.08 μg/g. All the concentrations of Pb in indoor air were higher than in outdoor air at all sampling stations. The concentrations of cations and anions were higher in outdoor air than in indoor air. The concentration ofCa2+(39.51 ± 5.01 mg/g–65.13 ± 9.42 mg/g) was the highest because the cation existed naturally in soil dusts, while the concentrations ofNO3-andSO42-were higher in outdoor air because there were more sources of exposure for anions in outdoor air, such as highly congested traffic and motor vehicles emissions. In comparison, the concentration ofNO3-(29.72 ± 0.31 μg/g–32.00 ± 0.75 μg/g) was slightly higher thanSO42-. The concentrations of most of the parameters in this study, such asMg2+,Ca2+,NO3-,SO42-, andPb2+, were higher in outdoor air than in indoor air at all sampling stations.

scholarly journals Turbulence Effect of Urban-Canopy Flow on Indoor Velocity Fields under Sheltered and Cross-Ventilation Conditions

2021 ◽  
Vol 13 (2) ◽  
pp. 586
Author(s):  
Ahmad Faiz Mohammad ◽  
Naoki Ikegaya ◽  
Ryo Hikizu ◽  
Sheikh Ahmad Zaki
Keyword(s):  
Wind Speed ◽  
Turbulent Flows ◽  
Indoor Air ◽  
Urban Canopy ◽  
Outdoor Air ◽  
Coverage Ratio ◽  
Turbulent Characteristics ◽  
Air Flows ◽  
Urban Canopy Flow ◽  
Indoor And Outdoor

Understanding the characteristics of natural, wind-induced ventilation of buildings is essential for accurate predictions of ventilation flow rates; however, indoor ventilation is significantly influenced by surrounding buildings. Therefore, a series of wind-tunnel experiments were performed to clarify the relationship between outdoor and indoor air flows around and within a target cube model with several openings. Two surrounding building arrangements, namely square (SQ) and staggered (ST), were placed under the condition of a building coverage ratio of 25%. The results indicated that the wind speed near the windward openings on the streamwise faces showed 0.3 to the reference wind speed, whereas those on the lateral faces were less than 0.1; these numbers indicate that the opening positions significantly affect the mean indoor wind speed. Furthermore, the temporal fluctuations of velocities near the opening demonstrated that the introduction of the flow is significantly affected by turbulent flow due to the surrounding buildings. In addition, correlation between the outdoor and indoor air flows was observed. The highest correlations were obtained for both opening conditions with a certain temporal delay. This result indicates that indoor air flows become turbulent because of the turbulent flows generated by the surrounding outdoor buildings; however, slight temporal delays could occur between indoor and outdoor air flows. Although the present study focuses on the fundamental turbulent characteristics of indoor and outdoor air flows, such findings are essential for accurately predicting the ventilation flow rate due to turbulent air flows for sheltered buildings.

Indoor Air Pollution as an Environmental Factor

1976 ◽  
Vol 20 (14) ◽  
pp. 272-276
Author(s):  
Joshi Satish
Keyword(s):  
Air Pollution ◽  
Indoor Air ◽  
Indoor Air Pollution ◽  
Well Being ◽  
Outdoor Air ◽  
Average Person ◽  
Sampling Program ◽  
The City ◽  
Indoor And Outdoor

An average person spends most of his time indoors and the quality of indoor air affects his performance and well-being. This justifies the study of indoor air pollution for the development of working and living environments which are comfortable and safe. As a part of a larger program to study traffic-generated air pollution in the vicinity of streets, a simultaneous indoor/outdoor sampling program was carried out at three sites in the city of Zurich, Switzerland. Parameters included CO, NO, NO2 and HCHO. The results show the direct relationship between indoor and outdoor concentrations of CO, NO and NO2. HCHO concentrations were found to be substantially higher indoors than ourdoors thus supporting the hypothesis that HCHO source could be in the buildings themselves. The importance of indoor air is emphasized, and the interplay of indoor and outdoor air pollution is demonstrated.

scholarly journals The identification of Volatile Organic Compound’s emission sources in indoor air of living spaces, offices and laboratories

2018 ◽  
Vol 28 ◽  
pp. 01018
Author(s):  
Beata Kultys
Keyword(s):  
Air Quality ◽  
Indoor Air ◽  
Correlation Coefficients ◽  
Well Being ◽  
Emission Sources ◽  
Outdoor Air ◽  
Volatile Organic ◽  
Sick Building ◽  
Work Type ◽  
Indoor And Outdoor

Indoor air quality is important because people spend most of their time in closed rooms. If volatile organic compounds (VOCs) are present at elevated concentrations, they may cause a deterioration in human well-being or health. The identification of indoor emission sources is carried out by comparison indoor and outdoor air composition. The aim of the study was to determinate the concentration of VOCs in indoor air, where there was a risk of elevated levels due to the kind of work type carried out or the users complained about the symptoms of a sick building followed by an appropriate interpretation of the results to determine whether the source of the emission in the tested room occurs. The air from residential, office and laboratory was tested in this study. The identification of emission sources was based on comparison of indoor and outdoor VOCs concentration and their correlation coefficients. The concentration of VOCs in all the rooms were higher or at a similar level to that of the air sampled at the same time outside the building. Human activity, in particular repair works and experiments with organic solvents, has the greatest impact on deterioration of air quality.

Microplastics Differ Between Indoor and Outdoor Air Masses: Insights from Multiple Microscopy Methodologies

2020 ◽  
Vol 74 (9) ◽  
pp. 1079-1098 ◽  
Author(s):  
Emily Gaston ◽  
Mary Woo ◽  
Clare Steele ◽  
Suja Sukumaran ◽  
Sean Anderson
Keyword(s):  
Indoor Air ◽  
Fluorescent Microscopy ◽  
Inhalation Exposure ◽  
Nile Red ◽  
Outdoor Air ◽  
Air Masses ◽  
Ft Ir ◽  
Abundance And Distribution ◽  
Microscopy Techniques ◽  
Indoor And Outdoor

The abundance and distribution of microplastic (<5 mm) has become a growing concern, particularly over the past decade. Research to date has focused on water, soil, and organism matrices but generally disregarded air. We explored airborne microplastic inside and outside of buildings in coastal California by filtering known volumes of air through glass fiber filters, which were then subsequently characterized with a variety of microscopy techniques: gross traditional microscopy, fluorescent microscopy following staining with Nile red, micro-Raman spectroscopy, and micro-Fourier transform infrared (µFT-IR) spectroscopy. Microplastics permeated the air, with indoor (3.3 ± 2.9 fibers and 12.6 ± 8.0 fragments m–3; mean ± 1 SD) harboring twice as much as outdoor air (0.6 ± 0.6 fibers and 5.6 ± 3.2 fragments m–3). Microplastic fiber length did not differ significantly between indoor and outdoor air, but indoor microplastic fragments (58.6 ± 55 µm) were half the size of outdoor fragments (104.8 ± 64.9 µm). Micro-Raman and FT-IR painted slightly different pictures of airborne plastic compounds, with micro-Raman suggesting polyvinyl chloride dominates indoor air, followed by polyethylene (PE) and µFT-IR showing polystyrene dominates followed by PE and polyethylene terephthalate. The ubiquity of airborne microplastic points to significant new potential sources of plastic inputs to terrestrial and marine ecosystems and raises significant concerns about inhalation exposure to humans both indoors and outdoors.

Mycotoxins in the ventilation systems of four schools in Finland

2009 ◽  
Vol 2 (4) ◽  
pp. 369-379 ◽  
Author(s):  
E. Hintikka ◽  
R. Holopainen ◽  
A. Asola ◽  
M. Jestoi ◽  
M. Peitzsch ◽  
...  
Keyword(s):  
Indoor Air ◽  
Building Materials ◽  
Fungal Species ◽  
School Buildings ◽  
Penicillic Acid ◽  
Air Samples ◽  
Ventilation Ducts ◽  
Chaetoglobosin A ◽  
Indoor And Outdoor ◽  
Ventilation Systems

Some fungal species have been listed as a problem causing fungi in indoor air and most of this group are known to produce mycotoxins. So far, mycotoxins have been found in building materials and in samples representing settled indoor air dust, as well in air samples from industrial or agricultural environments. The present paper presents the results of a mycological study and mycotoxin analyses of dust collected from mechanical ventilation systems in four school buildings in southern Finland. The aim of this work was to answer the question 'Are there mycotoxins in ventilation systems and if so, from where do they originate?' A total of 40 mycotoxins representing indoor and outdoor sources alike were screened in this study, while cultivable fungi were screened using four different cultivation media. Mycotoxins were present in all ventilation systems studied, both in the supply and the exhaust systems examined. The mycotoxins found included satratoxins, verrucarol, trichodermol, enniatins, beauvericin, penicillic acid, sterigmatocystin, chaetoglobosin A, and aflatoxins B1. The mycotoxins were present in minute quantities (pg-ng/g or pg-ng/cm2). The fungal genera associated with respective mycotoxins were found in most of the same sources. Since much the same mycotoxins could be established in both exhaust and supply air systems, it would appear that the mycotoxins found in the schools studied do not for the most part originate from sources within the building but are either normal artefacts of incoming supply air or concentrate or are perhaps produced within the ventilation systems due to infrequent changing of filters and maintenance/cleaning of ventilation ducts and associated parts of the systems.

Sign in / Sign up

Export Citation Format

Share Document