Read by QxMD icon Read

Indoor Air

Stefano Schiavon, Bin Yang, Yoni Donner, Victor W-C Chang, William W Nazaroff
In a warm and humid climate, increasing the temperature setpoint offers considerable energy benefits with low first costs. Elevated air movement generated by a personally controlled fan can compensate for the negative effects caused by an increased temperature setpoint. Fifty-six tropically acclimatized persons in common Singaporean office attire (0.7 clo) were exposed for 90 minutes to each of five conditions: 23, 26, and 29 °C and in the latter two cases with and without occupant controlled air movement...
October 18, 2016: Indoor Air
Guozhu Zhao, Guohua Yin, Arati A Inamdar, Jing Luo, Ning Zhang, Ill Yang, Brian Buckley, Joan W Bennett
Super Storm Sandy provided an opportunity to study filamentous fungi (molds) associated with winter storm damage. We collected 36 morphologically distinct fungal isolates from flooded buildings. By combining traditional morphological and cultural characters with an analysis of ITS sequences (the fungal DNA barcode), we identified 24 fungal species that belong to 8 genera: Penicillium (12 species), Fusarium (4 species), Aspergillus (3 species), Trichoderma (2 species), and one species each of Metarhizium, Mucor, Pestalotiopsis, and Umbelopsis...
October 17, 2016: Indoor Air
Jin Zhou, Wenjuan Fang, Qingliang Cao, Linyan Yang, Victor W-C Chang, William W Nazaroff
Utilizing the ultraviolet-light induced fluorescence (UV-LIF) measurement technique as embodied in the Waveband-Integrated Bioaerosol Sensor (WIBS-4A), we evaluated the fluorescent particle emissions associated with human shedding while walking in a chamber. The mean emission rates of supermicron (1-10 μm) fluorescent particles was in the range 6.8-7.5 million particles per person-h (~ 0.3 mg per person-h) across three participants, for conditions when the relative humidity was 60-70% and no moisturizer was applied after showering...
October 17, 2016: Indoor Air
Annette Menzel, Michael Matiu, Rico Michaelis, Susanne Jochner
Indoor pollen concentrations are an underestimated human health issue. In this study, we measured hourly indoor birch pollen concentrations on eight days in April 2015 with portable pollen traps in five rooms of a university building at Freising, Germany. These data were compared to the respective outdoor values right in front of the rooms and to background pollen data. The rooms were characterised by different aspects and window ventilation schemes. Meteorological data were equally measured directly in front of the windows...
October 17, 2016: Indoor Air
Joanne B Emerson, Patricia B Keady, Nicholas Clements, Emily E Morgan, Jonathan Awerbuch, Shelly L Miller, Noah Fierer
Our homes are microbial habitats, and although the amounts and types of bacteria in indoor air have been shown to vary substantially across residences, temporal variability within homes has rarely been characterized. Here, we sought to quantify the temporal variability in the amounts and types of airborne bacteria in homes, and what factors drive this variability. We collected filter samples of indoor and outdoor air in 15 homes over one year (approximately 8 time points per home, 2 per season), and we used culture-independent DNA sequencing approaches to characterize bacterial community composition...
October 15, 2016: Indoor Air
Janet M Macher, Mark J Mendell, Wenhao Chen, Kazukiyo Kumagai
Subjective indicators of building dampness consistently have been linked to health, but they are, at best, semi-quantitative, and objective and quantitative assessments of dampness are also needed to study dampness-related health effects. Investigators can readily and non-destructively measure the "moisture content" of building materials with hand-held moisture meters. However, moisture content does not indicate the amount of the water in a material that is available to microorganisms for growth, i.e., the "water activity...
October 14, 2016: Indoor Air
P W Francisco, D E Jacobs, L Targos, S L Dixon, J Breysse, W Rose, S Cali
Ventilation standards, health, and indoor air quality have not been adequately examined for residential weatherization. This randomized trial showed how ASHRAE 62-1989 (n=39 houses) and ASHRAE 62.2-2010 (n=42 houses) influenced ventilation rates, moisture balance, indoor air quality, and self-reported physical and mental health outcomes. Average total airflow was nearly twice as high for ASHRAE 62.2-2010 (79 vs. 39 cfm). Volatile organic compounds, formaldehyde and carbon dioxide were all significantly reduced for the newer standard and first-floor radon was marginally lower, but for the older standard, only formaldehyde significantly decreased...
October 6, 2016: Indoor Air
S Veselá, B R M Kingma, A J H Frijns
Local thermal sensation modeling gained importance due to developments in personalized and locally applied heating and cooling systems in office environments. The accuracy of these models depends on skin temperature prediction by thermophysiological models, which in turn rely on accurate environmental and personal input data. Environmental parameters are measured or prescribed, but personal factors such as clothing properties and metabolic rates have to be estimated. Data for estimating the overall values of clothing properties and metabolic rates are available in several papers and standards...
October 6, 2016: Indoor Air
X Triadó-Margarit, M Veillette, C Duchaine, M Talbot, F Amato, M C Minguillón, V Martins, E de Miguel, E O Casamayor, T Moreno
Subway systems worldwide transport more than 100 million people daily, therefore air quality on station platforms and inside trains is an important urban air pollution issue. We examined the microbiological composition and abundance in space and time of bioaerosols collected in the Barcelona subway system during a cold period. Quantitative PCR was used to quantify total bacteria, Aspergillus fumigatus, influenza A and B and rhinoviruses. Multitag 454 pyrosequencing of the 16S rRNA gene was used to assess bacterial community composition and biodiversity...
September 30, 2016: Indoor Air
M J Mendell, K Kumagai
An important proportion of respiratory illness is considered attributable to residential dampness or mold (D/M). Developing health-protective D/M guidelines has been challenging, in part because unhealthy levels of indoor D/M cannot be defined using available microbiological measurements. This review paper explores reported multilevel, observation-based (eg visual or olfactory) D/M metrics for potential in defining unhealthy levels of residential D/M. For many of the 33 multilevel residential D/M metrics identified, health risks generally increased as observed D/M increased...
September 24, 2016: Indoor Air
Mei Ling Chua, Magdiel Inggrid Setyawati, Huaqiong Li, Yu Fang Crystal Hay, Subramaniam Gurusamy, Florence Teoh, David Tai Leong, Saji George
We investigated the physicochemical properties (size, shape, elemental composition, and endotoxin) of size resolved particulate matter (PM) collected from the indoor and corridor environments of classrooms. A comparative hazard profiling of these PM was conducted using human microvascular endothelial cells (HMVEC). Oxidative stress dependent cytotoxicity responses were assessed using quantitative reverse transcriptase polymerase chain reaction (RT-PCR) and high content screening (HCS) and disruption of monolayer cell integrity was assessed using fluorescence microscopy and transwell assay...
September 23, 2016: Indoor Air
Tina Hoang, Rosemary Castorina, Fraser Gaspar, Randy Maddalena, Peggy L Jenkins, Qunfang Zoe Zhang, Thomas E McKone, Emilio Benfenati, Alex Y Shi, Asa Bradman
Little information exists about exposures to volatile organic compounds (VOCs) in early childhood education (ECE) environments. We measured 38 VOCs in single-day air samples collected in 2010-2011 from 34 ECE facilities serving California children and evaluated potential health risks. We also examined unknown peaks in the GC/MS chromatographs for indoor samples and identified 119 of these compounds using mass spectral libraries. VOCs found in cleaning and personal care products had the highest indoor concentrations (d-limonene and decamethylcyclopentasiloxane [D5] medians: 33...
September 22, 2016: Indoor Air
H S Jang, H Lim, J Y Jeon
The effect of interior materials with various absorption coefficients on speech privacy was investigated in a 1:10 scale model of one high-speed train cabin geometry. The speech transmission index (STI) and privacy distance (rP ) were measured in the train cabin to quantify speech privacy. Measurement cases were selected for the ceiling, sidewall, and front and back walls and were classified as high-, medium- and low-absorption coefficient cases. Interior materials with high absorption coefficients yielded a low rP , and the ceiling had the largest impact on both the STI and rP among the interior elements...
September 17, 2016: Indoor Air
I Liagkouridis, E Cequier, B Lazarov, A Palm Cousins, C Thomsen, M Stranger, I T Cousins
A significant number of consumer goods and building materials can act as emission sources of flame retardants (FRs) in the indoor environment. We investigate the relationship between the emission source strength and the levels of 19 brominated flame retardants (BFRs) and seven organophosphate flame retardants (OPFRs) in air and dust collected in 38 indoor microenvironments in Norway. We use modeling methods to back-calculate emission rates from indoor air and dust measurements and identify possible indications of an emission-to-dust pathway...
September 10, 2016: Indoor Air
K Morisseau, A Joubert, L Le Coq, Y Andres
This study aimed to demonstrate that particles, especially those associated with fungi, could be released from fibrous filters used in the air-handling unit (AHU) of heating, ventilation and air-conditioning (HVAC) systems during ventilation restarts. Quantification of the water retention capacity and SEM pictures of the filters was used to show the potential for fungal proliferation in unused or preloaded filters. Five fibrous filters with various particle collection efficiencies were studied: classes G4, M5, M6, F7, and combined F7 according to European standard EN779:2012...
August 26, 2016: Indoor Air
B Koelblen, A Psikuta, A Bogdan, S Annaheim, R M Rossi
Thermal sensation models, capable of predicting human's perception of thermal surroundings, are commonly used to assess given indoor conditions. These models differ in many aspects, such as the number and type of input conditions, the range of conditions in which the models can be applied, and the complexity of equations. Moreover, the models are associated with various thermal sensation scales. In this study, a systematic comparison of seven existing thermal sensation models has been performed with regard to exposures including various air temperatures, clothing thermal insulation, and metabolic rate values after a careful investigation of the models' range of applicability...
August 26, 2016: Indoor Air
A Saini, J O Okeme, J Mark Parnis, R H McQueen, M L Diamond
Uptake kinetics of semi-volatile organic compounds (SVOCs) present indoors, namely phthalates and halogenated flame retardants (HFRs), were characterized for cellulose-based cotton and rayon fabrics. Cotton and rayon showed similar accumulation of gas- and particle-phase SVOCs, when normalized to planar surface area. Accumulation was 3-10 times greater by rayon than cotton, when normalized to Brunauer-Emmett-Teller (BET) specific surface area which suggests that cotton could have a longer linear uptake phase than rayon...
August 24, 2016: Indoor Air
Gabriel Bekö, Glenn Morrison, Charles J Weschler, Holger M Koch, Claudia Pälmke, Tunga Salthammer, Tobias Schripp, Jørn Toftum, Geo Clausen
In this preliminary study we have investigated if dermal uptake of nicotine directly from air or indirectly from clothing can be a meaningful exposure pathway. Two participants wearing only shorts and a third participant wearing clean cotton clothes were exposed to environmental tobacco smoke (ETS), generated by mechanically "smoking" cigarettes, for three hours in a chamber while breathing clean air from head-enveloping hoods. The average nicotine concentration (420 μg/m(3) ) was comparable to the highest levels reported for smoking sections of pubs...
August 24, 2016: Indoor Air
O V Voloshina, E A Shirshin, J Lademann, V V Fadeev, M E Darvin
We propose a fluorescence method for protein content assessment in fine house dust, which can be used as an indicator of the hygienic state of occupied rooms. The results of the measurements performed with 30 house dust samples, including ultrafiltration experiments, strongly suggest that the fluorescence emission of house dust extracts excited at 350 nm is mainly due to protein fragments, which are presumably keratin hydrolysates. This suggestion is supported by several facts: (i) Spectral band shapes for all the samples under investigation are close and correspond to that of keratin; (ii) fluorescence intensity correlates with the total protein content as provided by Lowry assay; (iii) treatment of the samples with proteinase K, which induces keratin hydrolysis, results in fluorescence enhancement without changing fluorescence band shape; and (iv) Raman spectra of keratin and fine house dust samples exhibit a very similar structure...
August 19, 2016: Indoor Air
William W Nazaroff
No abstract text is available yet for this article.
October 2016: Indoor Air
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"