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Hageman G, van Broekhuizen P, Nihom J. The role of nanoparticles in bleed air in the etiology of Aerotoxic Syndrome: A review of cabin air-quality studies of 2003-2023. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2024:1-16. [PMID: 38593380 DOI: 10.1080/15459624.2024.2327348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Aerotoxic Syndrome may develop as a result of chronic, low-level exposure to organophosphates (OPs) and volatile organic compounds in the airplane cabin air, caused by engine oil leaking past wet seals. Additionally, acute high-level exposures, so-called "fume events," may occur. However, air quality monitoring studies concluded that levels of inhaled chemicals might be too low to cause adverse effects. The presence of aerosols of nanoparticles (NPs) in bleed air has often been described. The specific hypothesis is a relation between NPs acting as a vector for toxic compounds in the etiology of the Aerotoxic Syndrome. These NPs function as carriers for toxic engine oil compounds leaking into the cabin air. Inhaled by aircrew NPs carrying soluble and insoluble components deposit in the alveolar region, where they are absorbed into the bloodstream. Subsequently, they may cross the blood-brain barrier and release their toxic compounds in the central nervous system. Olfactory absorption is another route for NPs with access to the brain. To study the hypothesis, all published in-flight measurement studies (2003-2023) of airborne volatile (and low-volatile) organic pollutants in cabin air were reviewed, including NPs (10-100 nm). Twelve studies providing data for a total of 387 flights in 16 different large-passenger jet aircraft types were selected. Maximum particle number concentrations (PNC) varied from 104 to 2.8 × 106 #/cm3 and maximum mass concentrations from 9 to 29 μg/m3. NP-peaks occurred after full-power take-off, in tailwind condition, after auxiliary power unit (APU) bleed air introduction, and after air conditioning pack failure. Chemical characterization of the NPs showed aliphatic hydrocarbons, black carbon, and metallic core particles. An aerosol mass-spectrometry pattern was consistent with aircraft engine oil. It is concluded that chronic exposure of aircrew to NP-aerosols, carrying oil derivatives, maybe a significant feature in the etiology of Aerotoxic Syndrome. Mobile NP measuring equipment should be made available in the cockpit for long-term monitoring of bleed air. Consequently, risk assessment of bleed air should include monitoring and analysis of NPs, studied in a prospective cohort design.
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Affiliation(s)
- G Hageman
- Department of Neurology, Medisch Spectrum Twente, Hospital Enschede, Enschede, The Netherlands
| | - P van Broekhuizen
- Department of Environmental Studies (IVAM), University of Amsterdam, Amsterdam, The Netherlands
| | - J Nihom
- Department of Neurology, Medisch Spectrum Twente, Hospital Enschede, Enschede, The Netherlands
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Abidi M, Abou Saoud W, Bouzaza A, Hajjaji A, Bessais B, Wolbert D, Assadi A, Rtimi S. Dynamics of VOCs degradation and bacterial inactivation at the interface of AgxO/Ag/TiO2 prepared by HiPIMS under indoor light. J Photochem Photobiol A Chem 2022. [DOI: 10.1016/j.jphotochem.2022.114321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Yin Y, He J, Zhao L, Pei J, Yang X, Sun Y, Cui X, Lin CH, Wei D, Chen Q. Identification of key volatile organic compounds in aircraft cabins and associated inhalation health risks. ENVIRONMENT INTERNATIONAL 2022; 158:106999. [PMID: 34991259 DOI: 10.1016/j.envint.2021.106999] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 11/18/2021] [Accepted: 11/22/2021] [Indexed: 05/05/2023]
Abstract
The identification of key VOCs during flights is important in creating a satisfactory aircraft cabin environment. Two VOC databases for the building indoor environment (from 251 occupied residences) and the aircraft cabin environment (from 56 commercial flights) were compared, to determine the common compounds (detection rate (DR) > 70%) in the two environments and the characteristic VOCs (only those with high DR during flights) in aircraft cabins. Possible VOC emission sources in flights were also discussed. As TVOC is usually viewed as a general indicator of air quality, the prediction of TVOC concentration was carried out using BP neural network algorithm, and the average error between the predicted and measured values was 55.35 μg/m3 (R2 = 0.80). Meanwhile, the VOCs' inhalation cancer/non-cancer risks to crew members and passengers were calculated on the basis of detection rates, exposure concentrations, and health risk assessments. Six compounds (i.e., formaldehyde, benzene, tetrachloroethylene, trichloromethane, 1,2-dichloroethane, and naphthalene) were proposed as the key VOCs in the existing aircraft cabin environment, presenting a risk to crew members that is higher than the US EPA proposed acceptable level (evaluated mean value > 1E-06). The estimated lifetime excess cancer/non-cancer risks for passengers were all below the assessment criteria. Based on a summary of various VOC limits in five built environments, hierarchical design of VOC concentration limits is recommended for the aircraft environment.
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Affiliation(s)
- Yihui Yin
- Tianjin Key Laboratory of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Junzhou He
- Department of Building Science, Tsinghua University, Beijing 100084, China
| | - Lei Zhao
- Tianjin Key Laboratory of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Jingjing Pei
- Tianjin Key Laboratory of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China.
| | - Xudong Yang
- Department of Building Science, Tsinghua University, Beijing 100084, China
| | - Yuexia Sun
- Tianjin Key Laboratory of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Xikang Cui
- COMAC Beijing Aircraft Technology Research Institute, Beijing 102211, China
| | - Chao-Hsin Lin
- Environmental Control Systems, Boeing Commercial Airplanes, Everett, WA 98203, USA
| | - Daniel Wei
- Boeing Research & Technology - China, Beijing 100027, China
| | - Qingyan Chen
- School of Mechanical Engineering, Purdue University, West Lafayette, IN, USA
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Yin Y, He J, Pei J, Yang X, Sun Y, Cui X, Lin CH, Wei D, Chen Q. Influencing factors of carbonyl compounds and other VOCs in commercial airliner cabins: On-board investigation of 56 flights. INDOOR AIR 2021; 31:2084-2098. [PMID: 34240486 DOI: 10.1111/ina.12903] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 06/23/2021] [Accepted: 06/24/2021] [Indexed: 06/13/2023]
Abstract
Volatile organic compounds (VOCs) as a non-negligible aircraft cabin air quality (CAQ) factor influence the health and comfort of passengers and crew members. On-board measurements of carbonyls (short-chain (C1 -C6 )) and other volatile organic compounds (VOCs, long-chain (C6 -C16 )) with a total of 350 samples were conducted in 56 commercial airliner cabins covering 8 aircraft models in this study. The mean concentration for each individual carbonyl compound was between 0.3 and 8.3 μg/m3 (except for acrolein & acetone, average = 20.7 μg/m3 ) similar to the mean concentrations of other highly detected VOCs (long-chain (C6 -C16 ), 97% of which ranged in 0-10 μg/m3 ) in aircraft cabins. Formaldehyde concentrations in flights were significantly lower than in residential buildings, where construction materials are known formaldehyde sources. Acetone is a VOC emitted by humans, and its concentration in flights was similar to that in other high-occupant density transportation vehicles. The variation of VOC concentrations in different flight phases of long-haul flights was the same as that of CO2 concentration except for the meal phase, which indicates the importance of cabin ventilation in diluting the gaseous contaminants, while the sustained and slow growth of the VOC concentrations during the cruising phase in short-haul flights indicated that the ventilation could not adequately dilute the emission of VOCs. For the different categories of VOCs, the mean concentration during the cruising phase of benzene series, aldehydes, alkanes, other VOCs (detection rate > 50%), and carbonyls in long-haul flights was 44.2 µg/m3 , 17.9 µg/m3 , 18.6 µg/m3 , 31.5 µg/m3 , and 20.4 µg/m3 lower than those in short-haul flights, respectively. Carbonyls and d-limonene showed a significant correlation with meal service (p < 0.05). Unlike the newly decorated rooms or new vehicles, the inner materials were not the major emission sources in aircraft cabins. Practical Implications. The on-board measurements of 56 flights enrich the VOC database of cabin environment, especially for carbonyls. The literature review of carbonyls in the past 20 years contributes to the understanding the current status of cabin air quality (CAQ). The analysis of VOC concentration variation for different flight phases, flight duration, and aircraft age lays a foundation for exploring effective control methods, including ventilation and purification for cabin VOC pollution. The enriched VOC data is helpful to explore the key VOCs of aircraft cabin environment and to evaluate the acute/chronic health exposure risk of pollutants for passengers and crew members.
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Affiliation(s)
- Yihui Yin
- Tianjin Key Laboratory of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Junzhou He
- Department of Building Science, Tsinghua University, Beijing, China
| | - Jingjing Pei
- Tianjin Key Laboratory of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Xudong Yang
- Department of Building Science, Tsinghua University, Beijing, China
| | - Yuexia Sun
- Tianjin Key Laboratory of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Xikang Cui
- COMAC Beijing Aircraft Technology Research Institute, Beijing, China
| | - Chao-Hsin Lin
- Environmental Control Systems, Boeing Commercial Airplanes, WA, USA
| | - Daniel Wei
- Boeing Research & Technology, Beijing, China
| | - Qingyan Chen
- School of Mechanical Engineering, Purdue University, IN, USA
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Chen R, Fang L, Liu J, Herbig B, Norrefeldt V, Mayer F, Fox R, Wargocki P. Cabin air quality on non-smoking commercial flights: A review of published data on airborne pollutants. INDOOR AIR 2021; 31:926-957. [PMID: 33896039 DOI: 10.1111/ina.12831] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/15/2021] [Indexed: 05/24/2023]
Abstract
We reviewed 47 documents published 1967-2019 that reported measurements of volatile organic compounds (VOCs) on commercial aircraft. We compared the measurements with the air quality standards and guidelines for aircraft cabins and in some cases buildings. Average levels of VOCs for which limits exist were lower than the permissible levels except for benzene with average concentration at 5.9 ± 5.5 μg/m3 . Toluene, benzene, ethylbenzene, formaldehyde, acetaldehyde, limonene, nonanal, hexanal, decanal, octanal, acetic acid, acetone, ethanol, butanal, acrolein, isoprene and menthol were the most frequently measured compounds. The concentrations of semi-volatile organic compounds (SVOCs) and other contaminants did not exceed standards and guidelines in buildings except for the average NO2 concentration at 12 ppb. Although the focus was on VOCs, we also retrieved the data on other parameters characterizing cabin environment. Ozone concentration averaged 38 ppb below the upper limit recommended for aircraft. The outdoor air supply rate ranged from 1.7 to 39.5 L/s per person and averaged 6.0 ± 0.8 L/s/p (median 5.8 L/s/p), higher than the minimum level recommended for commercial aircraft. Carbon dioxide concentration averaged 1315 ± 232 ppm, lower than what is permitted in aircraft and close to what is permitted in buildings. Measured temperatures averaged 23.5 ± 0.8°C and were generally within the ranges recommended for avoiding thermal discomfort. Relative humidity averaged 16% ± 5%, lower than what is recommended in buildings.
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Affiliation(s)
- Ruiqing Chen
- Tianjin Key Laboratory of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Lei Fang
- International Centre for Indoor Environment and Energy, Department of Civil Engineering, Technical University of Denmark, Lyngby, Denmark
| | - Junjie Liu
- Tianjin Key Laboratory of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Britta Herbig
- LMU University Hospital Munich, Institute and Clinic for Occupational, Social and Environmental Medicine, Munich, Germany
| | - Victor Norrefeldt
- Fraunhofer Institute for Building Physics IBP, Holzkirchen Branch, Valley, Germany
| | - Florian Mayer
- Fraunhofer Institute for Building Physics IBP, Holzkirchen Branch, Valley, Germany
| | - Richard Fox
- Aircraft Environment Solutions Inc., San Tan Valley, Arizona, USA
| | - Pawel Wargocki
- International Centre for Indoor Environment and Energy, Department of Civil Engineering, Technical University of Denmark, Lyngby, Denmark
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6
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Bioaerosol Contribution to Atmospheric Particulate Matter in Indoor University Environments. SUSTAINABILITY 2021. [DOI: 10.3390/su13031149] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Within the framework of the project “Integrated Evaluation of Indoor Particulate Exposure”, we carried out a 4-week field study to determine indoor bioaerosol, and its contribution to particulate matter (PM)10 and organic matter. The study was carried out in university classrooms, where most of the common indoor sources of atmospheric particles are missing. Bioaerosol was determined by a method based on propidium iodide staining, observation by fluorescence microscopy, and image analysis. Indoor bioaerosol concentrations were compared with outdoor values, which were determined simultaneously. The samplings periods were scheduled to divide weekday hours, when the students were inside, from night-time hours and weekends. Very high bioaerosol concentrations were detected inside the classrooms with respect to outdoor values. The mean difference was 49 μg/m3 when the students were inside, 5.4 μg/m3 during the night, and it became negative during the weekends. Indoor-to-outdoor ratios were 6.0, 4.2, and 0.7, respectively. Bioaerosol contributed 26% to organics and 10% to PM10. In indoor samples collected during the day, the microscope images showed numerous skin fragments, which were mostly responsible for the increase in the bioaerosol mass. People’s presence proved to be responsible for a significant increase in bioaerosol concentration in crowded indoor environments.
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Yang S, Bekö G, Wargocki P, Williams J, Licina D. Human Emissions of Size-Resolved Fluorescent Aerosol Particles: Influence of Personal and Environmental Factors. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:509-518. [PMID: 33337850 DOI: 10.1021/acs.est.0c06304] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Human emissions of fluorescent aerosol particles (FAPs) can influence the biological burden of indoor air. Yet, quantification of FAP emissions from human beings remains limited, along with a poor understanding of the underlying emission mechanisms. To reduce the knowledge gap, we characterized human emissions of size-segregated FAPs (1-10 μm) and total particles in a climate chamber with low-background particle levels. We probed the influence of several personal factors (clothing coverage and age) and environmental parameters (level of ozone, air temperature, and relative humidity) on particle emissions from human volunteers. A material-balance model showed that the mean emission rate ranged 5.3-16 × 106 fluorescent particles per person-h (0.30-1.2 mg per person-h), with a dominant size mode within 3-5 μm. Volunteers wearing long-sleeve shirts and pants produced 40% more FAPs relative to those wearing t-shirts and shorts. Particle emissions varied across the age groups: seniors (average age 70.5 years) generated 50% fewer FAPs compared to young adults (25.0 years) and teenagers (13.8 years). While we did not observe a measurable influence of ozone (0 vs 40 ppb) on human FAP emissions, there was a strong influence of relative humidity (34 vs 62%), with FAP emissions decreasing by 30-60% at higher humidity.
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Affiliation(s)
- Shen Yang
- Human-Oriented Built Environment Lab, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Gabriel Bekö
- International Centre for Indoor Environment and Energy, Department of Civil Engineering, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Pawel Wargocki
- International Centre for Indoor Environment and Energy, Department of Civil Engineering, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Jonathan Williams
- Max Planck Institute for Chemistry, Hahn-Meitner Weg 1, 55128 Mainz, Germany
- Energy, Environment and Water Research Center, The Cyprus Institute, 2121 Nicosia, Cyprus
| | - Dusan Licina
- Human-Oriented Built Environment Lab, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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Sun Y, Fu X, Li Y, Yuan Q, Ou Z, Lindgren T, Deng Y, Norbäck D. Shotgun metagenomics of dust microbiome from flight deck and cabin in civil aviation aircraft. INDOOR AIR 2020; 30:1199-1212. [PMID: 32578244 DOI: 10.1111/ina.12707] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Revised: 03/30/2020] [Accepted: 06/14/2020] [Indexed: 05/14/2023]
Abstract
Microbial exposure is related to the health of passengers on commercial aircraft, but no studies characterized the microbial composition at the species level and identified their ecological determinants. We collected vacuum dust from floor and seat surfaces in flight decks and cabins of 18 aircraft, and amplification-free shotgun metagenomics was conducted to characterize the microbial composition. In total, 7437 microbial taxa were identified. The relative abundance for bacteria, eukaryote, viruses, and archaea was 96.9%, 1.8%, 0.3%, and 0.03%, respectively. The top bacterial species mainly derived from outdoor air and human skin included Sphingomonas, Corynebacterium, Micrococcus luteus, Variovorax paradoxus, Paracoccus dentrificans, and Propionibacterium acnes. The abundance of NIAID-defined pathogens was low, accounted for only 0.23% of total microbes. The microbial species and functional composition were structured by the indoor surface type (R2 = 0.38, Adonis), followed by the manufacturer of the aircraft (R2 = 0.12) and flight duration (R2 = 0.07). Indoor surfaces affected species derived from different habitats; the abundance of dry skin and desiccated species was higher on textile surfaces, whereas the abundance of moist and oily skin species was higher on leather surfaces. The growth rates for most microbes were stopped and almost stopped.
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Affiliation(s)
- Yu Sun
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, China
- Key Laboratory of Zoonosis of Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou, China
| | - Xi Fu
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, China
- Department of Occupational and Environmental Health, School of Public Health, Sun Yat-sen University, Guangzhou, China
| | - Yanling Li
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, China
- Key Laboratory of Zoonosis of Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou, China
| | - Qianqian Yuan
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, China
- Key Laboratory of Zoonosis of Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou, China
| | - Zheyuan Ou
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, China
- Key Laboratory of Zoonosis of Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou, China
| | - Torsten Lindgren
- Occupational and Environmental Medicine, Department of Medical Science, University Hospital, Uppsala University, Uppsala, Sweden
| | - Yiqun Deng
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, China
- Key Laboratory of Zoonosis of Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou, China
| | - Dan Norbäck
- Occupational and Environmental Medicine, Department of Medical Science, University Hospital, Uppsala University, Uppsala, Sweden
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Liu M, Liu J, Ren J, Liu L, Chen R, Li Y. Bacterial community in commercial airliner cabins in China. INTERNATIONAL JOURNAL OF ENVIRONMENTAL HEALTH RESEARCH 2020; 30:284-295. [PMID: 30897937 DOI: 10.1080/09603123.2019.1593329] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Accepted: 03/06/2019] [Indexed: 06/09/2023]
Abstract
Considering the amount of time that crew members and passengers spend on airliners and the potential health impact of pathogenic bacteria, it is important to understand the population of bacteria inside airliners and the factors affecting the bacterial concentration. This study recorded the species of airborne and cabin surface culturable bacteria inside various airliner. Seven flights ranging from 3 to 5 hours in duration on different types of airliner were chosen. Multiple species of bacteria in the air of the airliners, such as Brachybacterium paraconglomeratum, were identified by means of the 16S ribosomal RNA gene sequencing method, and most of the bacteria were Gram-positive. This study found that the bacterial concentration in the airliners decreases as the relative humidity increases. The decrease in the number of airborne bacteria may be the reason for the reduced occurrence of unwanted symptoms exhibited by passengers.
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Affiliation(s)
- Mingxin Liu
- Tianjin Key Lab of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Junjie Liu
- Tianjin Key Lab of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Jianlin Ren
- Tianjin Key Lab of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Lumeng Liu
- Tianjin Key Lab of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Ruiqing Chen
- Tianjin Key Lab of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Yanju Li
- School of Energy and Safety Engineering, Tianjin Chengjian University, Tianjin, China
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Wolkoff P. Indoor air chemistry: Terpene reaction products and airway effects. Int J Hyg Environ Health 2020; 225:113439. [PMID: 32044535 DOI: 10.1016/j.ijheh.2019.113439] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 12/04/2019] [Accepted: 12/18/2019] [Indexed: 12/15/2022]
Abstract
Reactive chemistry is ubiquitous indoors with a wealth of complex oxidation reactions; some of these are initiated by both homogeneous and heterogeneous reaction of ozone with unsaturated organic compounds and subsequent the hydroxyl radical, either in the gas-phase or on reactive surfaces. One major focus has been the reaction of common and abundant terpene-based fragrances in indoor air emitted from many wood-based materials, a variety of consumer products, and citrus fruits and flowers. Inhalation of the terpenes themselves are generally not considered a health concern (both acute and long-term) due to their low indoor air concentrations; however, their gas- and surface reactions with ozone and the hydroxyl radical produce a host of products, both gaseous, i. a. formaldehyde, and ultrafine particles formed by condensation/nucleation processes. These reaction products may be of health concern. Human cell bioassays with key reaction products from ozone-initiated terpene reactions have shown some inflammatory reactions, but results are difficult to interpret for human exposure and risk assessment. Acute effects like sensory irritation in eyes and airways are unlikely or present at very low intensity in real life conditions based on rodent and human exposure studies and known thresholds for sensory irritation in eyes and airways and derived human reference values for airflow limitation and pulmonary irritation. Some fragrances and their ozone-initiated reaction products may possess anti-inflammatory properties. However, long-term effects of the reaction products as ultrafine particles are poorly explored. Material and product surfaces with high ozone deposition velocities may significantly impact the perceived air quality by altered emissions from both homogeneous and heterogeneous surface reactions.
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Affiliation(s)
- Peder Wolkoff
- National Research Centre for the Working Environment, NRCWE, Lersø Parkallé 105, 2920, Copenhagen, Denmark.
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11
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In-Vehicle Exposures at Transportation and the Health Concerns. CURRENT TOPICS IN ENVIRONMENTAL HEALTH AND PREVENTIVE MEDICINE 2020. [PMCID: PMC7123345 DOI: 10.1007/978-981-32-9182-9_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In-vehicle environment is a special indoor environment, which is mobile, either open or closed. This chapter reviewed in-vehicle air quality and passenger exposures for roadway commuters, commercial airplanes, and marine transportation. The sources of pollutants in-vehicle can be categorized as the same as other indoor environments, including outdoor air, human activity, emission from building material and interior furnisher, and biological metabolic process from animals and microbes. However, the exposure in vehicles varies from now and then, influenced by window open/closed, speed, air flow, ventilation on/off, air conditioner on/off, pollutants from ambient outdoor air, interior material, and number of passengers. There are few studies on health condition of passengers, except infectious disease during airway transportation. Some health studies of related occupations are reviewed.
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12
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Cao Q, Chen C, Liu S, Lin CH, Wei D, Chen Q. Prediction of particle deposition around the cabin air supply nozzles of commercial airplanes using measured in-cabin particle emission rates. INDOOR AIR 2018; 28:852-865. [PMID: 29981175 DOI: 10.1111/ina.12489] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 06/27/2018] [Accepted: 06/28/2018] [Indexed: 06/08/2023]
Abstract
Enhanced soiling on the surfaces around air supply nozzles due to particle deposition is frequently observed in commercial airliners. The problem is worsened by severe outdoor air pollution and flight delays in China. The particles in an aircraft cabin originate from both outdoor and in-cabin sources. This study conducted measurements on multiple commercial flights to obtain particle emission rates from in-cabin sources. Additional experiments on a retired MD-82 airplane provided justification of the in-flight measurements. The in-cabin sources emitted more particles during boarding/deplaning than during meal servicing and sitting. The average PM2.5 emission rates were 7.2, 2.6, 1.9, and 1.8 (μg/min per person), respectively, during the boarding/deplaning, sitting on the ground, sitting in the air, and meal servicing. The corresponding PM10 emission rates were 15.4, 6.1, 5.3, and 5.4 (μg/min per person), respectively, for these four periods. The average particle emission rate from in-cabin sources varied seasonally and was the highest in winter. With the measured data, this investigation used a CFD model to predict the accumulation of particles deposited around the nozzles of an airplane, taking into account the flight routes and the outdoor particle concentrations at the airports where the airplanes were parked. For the most polluted airplane in China, the dirty spots/areas around the nozzles inside the airplane became visible after 6 months. The method proposed in this study can be used for any commercial airplane to predict the accumulation of particles deposited around the air supply nozzles.
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Affiliation(s)
- Qing Cao
- School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | - Chun Chen
- Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Hong Kong, China
| | - Sumei Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin, China
| | | | - Daniel Wei
- Boeing Research & Technology-China, Beijing, China
| | - Qingyan Chen
- School of Environmental Science and Engineering, Tianjin University, Tianjin, China
- School of Mechanical Engineering, Purdue University, West Lafayette, Indiana, USA
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13
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Yang L, Li X, Yan Y, Tu J. Effects of cough-jet on airflow and contaminant transport in an airliner cabin section. ACTA ACUST UNITED AC 2017. [DOI: 10.1177/1757482x17746920] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The goals of this study were to investigate the effect of cough-jet on local airflow and contaminant transport in a typical cabin environment by using computational fluid dynamics. A fully occupied airliner cabin section was employed as the computational domain. Contaminants were released through coughing passengers from different locations inside the cabin. Numerical results in terms of contaminant transport characteristics were examined and compared. It can be concluded that cough-jet has significant effects on air flow in front of cough passenger in a short period of time. Also, it was found that, without considering the cough-jet model, the simulation results could not be a precise representation of the transport and distribution of cough-generated airborne contaminants.
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Affiliation(s)
- Lin Yang
- School of Engineering, RMIT University, Bundoora, Australia
| | - Xiangdong Li
- School of Engineering, RMIT University, Bundoora, Australia
| | - Yihuan Yan
- School of Engineering, RMIT University, Bundoora, Australia
| | - Jiyuan Tu
- School of Engineering, RMIT University, Bundoora, Australia
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14
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Schwendner P, Mahnert A, Koskinen K, Moissl-Eichinger C, Barczyk S, Wirth R, Berg G, Rettberg P. Preparing for the crewed Mars journey: microbiota dynamics in the confined Mars500 habitat during simulated Mars flight and landing. MICROBIOME 2017; 5:129. [PMID: 28974259 PMCID: PMC5627443 DOI: 10.1186/s40168-017-0345-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 09/18/2017] [Indexed: 05/08/2023]
Abstract
BACKGROUND The Mars500 project was conceived as the first full duration simulation of a crewed return flight to Mars. For 520 days, six crew members lived confined in a specifically designed spacecraft mock-up. The herein described "MIcrobial ecology of Confined Habitats and humAn health" (MICHA) experiment was implemented to acquire comprehensive microbiota data from this unique, confined manned habitat, to retrieve important information on the occurring microbiota dynamics, the microbial load and diversity in the air and on various surfaces. In total, 360 samples from 20 (9 air, 11 surface) locations were taken at 18 time-points and processed by extensive cultivation, PhyloChip and next generation sequencing (NGS) of 16S rRNA gene amplicons. RESULTS Cultivation assays revealed a Staphylococcus and Bacillus-dominated microbial community on various surfaces, with an average microbial load that did not exceed the allowed limits for ISS in-flight requirements indicating adequate maintenance of the facility. Areas with high human activity were identified as hotspots for microbial accumulation. Despite substantial fluctuation with respect to microbial diversity and abundance throughout the experiment, the location within the facility and the confinement duration were identified as factors significantly shaping the microbial diversity and composition, with the crew representing the main source for microbial dispersal. Opportunistic pathogens, stress-tolerant or potentially mobile element-bearing microorganisms were predicted to be prevalent throughout the confinement, while the overall microbial diversity dropped significantly over time. CONCLUSIONS Our findings clearly indicate that under confined conditions, the community structure remains a highly dynamic system which adapts to the prevailing habitat and micro-conditions. Since a sterile environment is not achievable, these dynamics need to be monitored to avoid spreading of highly resistant or potentially pathogenic microorganisms and a potentially harmful decrease of microbial diversity. If necessary, countermeasures are required, to maintain a healthy, diverse balance of beneficial, neutral and opportunistic pathogenic microorganisms. Our results serve as an important data collection for (i) future risk estimations of crewed space flight, (ii) an optimized design and planning of a spacecraft mission and (iii) for the selection of appropriate microbial monitoring approaches and potential countermeasures, to ensure a microbiologically safe space-flight environment.
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Affiliation(s)
- Petra Schwendner
- Radiation Biology Department, Institute of Aerospace Medicine, German Aerospace Center e.V. (DLR), Linder Höhe, 51147 Cologne, Germany
- Institute for Microbiology, University of Regensburg, Universitaetsstrasse 31, 93053 Regensburg, Germany
- Present address: UK Center for Astrobiology, University of Edinburgh, School of Physics and Astronomy, Peter Guthrie Tait Road, Edinburgh, EH9 3FD UK
| | - Alexander Mahnert
- Institute of Environmental Biotechnology, Graz University of Technology, Petersgasse 12/I, 8010 Graz, Austria
| | - Kaisa Koskinen
- Medical University of Graz, Department of Internal Medicine, Auenbruggerplatz 15, 8036 Graz, Austria
- BioTechMed-Graz, Mozartgasse 12/II, 8010 Graz, Austria
| | - Christine Moissl-Eichinger
- Medical University of Graz, Department of Internal Medicine, Auenbruggerplatz 15, 8036 Graz, Austria
- BioTechMed-Graz, Mozartgasse 12/II, 8010 Graz, Austria
| | - Simon Barczyk
- Radiation Biology Department, Institute of Aerospace Medicine, German Aerospace Center e.V. (DLR), Linder Höhe, 51147 Cologne, Germany
| | - Reinhard Wirth
- Institute for Microbiology, University of Regensburg, Universitaetsstrasse 31, 93053 Regensburg, Germany
| | - Gabriele Berg
- Institute of Environmental Biotechnology, Graz University of Technology, Petersgasse 12/I, 8010 Graz, Austria
| | - Petra Rettberg
- Radiation Biology Department, Institute of Aerospace Medicine, German Aerospace Center e.V. (DLR), Linder Höhe, 51147 Cologne, Germany
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15
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Duchaine C. Assessing microbial decontamination of indoor air with particular focus on human pathogenic viruses. Am J Infect Control 2016; 44:S121-6. [PMID: 27590696 PMCID: PMC7115274 DOI: 10.1016/j.ajic.2016.06.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 06/03/2016] [Indexed: 11/21/2022]
Abstract
Transmission of bacterial, fungal, and viral pathogens is of primary importance in public and occupational health and infection control. Although several standardized protocols have been proposed to target microbes on fomites through surface decontamination, use of microbicidal agents, and cleaning processes, only limited guidance is available on microbial decontamination of indoor air to reduce the risk of pathogen transmission between individuals. This article reviews the salient aspects of airborne transmission of infectious agents, exposure assessment, in vitro assessment of microbicidal agents, and processes for air decontamination for infection prevention and control. Laboratory-scale testing (eg, rotating chambers, wind tunnels) and promising field-scale methodologies to decontaminate indoor air are also presented. The potential of bacteriophages as potential surrogates for the study of airborne human pathogenic viruses is also discussed.
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Affiliation(s)
- Caroline Duchaine
- Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec, Québec City, QC, Canada.
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16
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Bhangar S, Adams RI, Pasut W, Huffman JA, Arens EA, Taylor JW, Bruns TD, Nazaroff WW. Chamber bioaerosol study: human emissions of size-resolved fluorescent biological aerosol particles. INDOOR AIR 2016; 26:193-206. [PMID: 25704637 DOI: 10.1111/ina.12195] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 02/12/2015] [Indexed: 05/21/2023]
Abstract
Humans are a prominent source of airborne biological particles in occupied indoor spaces, but few studies have quantified human bioaerosol emissions. The chamber investigation reported here employs a fluorescence-based technique to evaluate bioaerosols with high temporal and particle size resolution. In a 75-m(3) chamber, occupant emission rates of coarse (2.5-10 μm) fluorescent biological aerosol particles (FBAPs) under seated, simulated office-work conditions averaged 0.9 ± 0.3 million particles per person-h. Walking was associated with a 5-6× increase in the emission rate. During both walking and sitting, 60-70% or more of emissions originated from the floor. The increase in emissions during walking (vs. while sitting) was mainly attributable to release of particles from the floor; the associated increased vigor of upper body movements also contributed. Clothing, or its frictional interaction with human skin, was demonstrated to be a source of coarse particles, and especially of the highly fluorescent fraction. Emission rates of FBAPs previously reported for lecture classes were well bounded by the experimental results obtained in this chamber study. In both settings, the size distribution of occupant FBAP emissions had a dominant mode in the 3-5 μm diameter range.
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Affiliation(s)
- S Bhangar
- Department of Civil and Environmental Engineering, University of California, Berkeley, CA, USA
| | - R I Adams
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
| | - W Pasut
- Center for the Built Environment, University of California, Berkeley, CA, USA
| | - J A Huffman
- Department of Chemistry and Biochemistry, University of Denver, Denver, CO, USA
| | - E A Arens
- Center for the Built Environment, University of California, Berkeley, CA, USA
| | - J W Taylor
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
| | - T D Bruns
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
| | - W W Nazaroff
- Department of Civil and Environmental Engineering, University of California, Berkeley, CA, USA
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17
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Wolkoff P, Crump DR, Harrison PTC. Pollutant exposures and health symptoms in aircrew and office workers: Is there a link? ENVIRONMENT INTERNATIONAL 2016; 87:74-84. [PMID: 26641522 DOI: 10.1016/j.envint.2015.11.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 11/04/2015] [Accepted: 11/09/2015] [Indexed: 06/05/2023]
Abstract
Sensory effects in eyes and airways are common symptoms reported by aircraft crew and office workers. Neurological symptoms, such as headache, have also been reported. To assess the commonality and differences in exposures and health symptoms, a literature search of aircraft cabin and office air concentrations of non-reactive volatile organic compounds (VOCs) and ozone-initiated terpene reaction products were compiled and assessed. Data for tricresyl phosphates, in particular tri-ortho-cresyl phosphate (ToCP), were also compiled, as well as information on other risk factors such as low relative humidity. A conservative health risk assessment for eye, airway and neurological effects was undertaken based on a "worst-case scenario" which assumed a simultaneous constant exposure for 8h to identified maximum concentrations in aircraft and offices. This used guidelines and reference values for sensory irritation for eyes and upper airways and airflow limitation; a tolerable daily intake value was used for ToCP. The assessment involved the use of hazard quotients or indexes, defined as the summed ratio(s) (%) of compound concentration(s) divided by their guideline value(s). The concentration data suggest that, under the assumption of a conservative "worst-case scenario", aircraft air and office concentrations of the compounds in question are not likely to be associated with sensory symptoms in eyes and airways. This is supported by the fact that maximum concentrations are, in general, associated with infrequent incidents and brief exposures. Sensory symptoms, in particular in eyes, appear to be exacerbated by environmental and occupational conditions that differ in aircraft and offices, e.g., ozone incidents, low relative humidity, low cabin pressure, and visual display unit work. The data do not support airflow limitation effects. For ToCP, in view of the conservative approach adopted here and the rareness of reported incidents, the health risk of exposure to this compound in aircraft is considered negligible.
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Affiliation(s)
- Peder Wolkoff
- National Research Centre for the Working Environment, Denmark.
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18
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Korves TM, Piceno YM, Tom LM, DeSantis TZ, Jones BW, Andersen GL, Hwang GM. Bacterial communities in commercial aircraft high-efficiency particulate air (HEPA) filters assessed by PhyloChip analysis. INDOOR AIR 2013; 23:50-61. [PMID: 22563927 PMCID: PMC7201892 DOI: 10.1111/j.1600-0668.2012.00787.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Accepted: 04/29/2012] [Indexed: 05/20/2023]
Abstract
UNLABELLED Air travel can rapidly transport infectious diseases globally. To facilitate the design of biosensors for infectious organisms in commercial aircraft, we characterized bacterial diversity in aircraft air. Samples from 61 aircraft high-efficiency particulate air (HEPA) filters were analyzed with a custom microarray of 16S rRNA gene sequences (PhyloChip), representing bacterial lineages. A total of 606 subfamilies from 41 phyla were detected. The most abundant bacterial subfamilies included bacteria associated with humans, especially skin, gastrointestinal and respiratory tracts, and with water and soil habitats. Operational taxonomic units that contain important human pathogens as well as their close, more benign relatives were detected. When compared to 43 samples of urban outdoor air, aircraft samples differed in composition, with higher relative abundance of Firmicutes and Gammaproteobacteria lineages in aircraft samples, and higher relative abundance of Actinobacteria and Betaproteobacteria lineages in outdoor air samples. In addition, aircraft and outdoor air samples differed in the incidence of taxa containing human pathogens. Overall, these results demonstrate that HEPA filter samples can be used to deeply characterize bacterial diversity in aircraft air and suggest that the presence of close relatives of certain pathogens must be taken into account in probe design for aircraft biosensors. PRACTICAL IMPLICATIONS A biosensor that could be deployed in commercial aircraft would be required to function at an extremely low false alarm rate, making an understanding of microbial background important. This study reveals a diverse bacterial background present on aircraft, including bacteria closely related to pathogens of public health concern. Furthermore, this aircraft background is different from outdoor air, suggesting different probes may be needed to detect airborne contaminants to achieve minimal false alarm rates. This study also indicates that aircraft HEPA filters could be used with other molecular techniques to further characterize background bacteria and in investigations in the wake of a disease outbreak.
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Affiliation(s)
- T. M. Korves
- Cognitive Tools and Data Management Department, The MITRE Corporation, Bedford, MA, USA
| | - Y. M. Piceno
- Ecology Department, Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - L. M. Tom
- Ecology Department, Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - T. Z. DeSantis
- Department of Bioinformatics, Second Genome, San Bruno, CA, USA
| | - B. W. Jones
- Department of Mechanical and Nuclear Engineering, Kansas State University, Manhattan, KS, USA
| | - G. L. Andersen
- Ecology Department, Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - G. M. Hwang
- Office of the Chief Engineer, The MITRE Corporation, Woodlawn, MD, USA
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19
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Poussou SB, Plesniak MW. Vortex dynamics and scalar transport in the wake of a bluff body driven through a steady recirculating flow. EXPERIMENTS IN FLUIDS 2012; 53:747-763. [PMID: 32214637 PMCID: PMC7087831 DOI: 10.1007/s00348-012-1325-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2011] [Revised: 04/01/2012] [Accepted: 05/18/2012] [Indexed: 05/05/2023]
Abstract
The air ventilation system in wide-body aircraft cabins provides passengers with a healthy breathing environment. In recent years, the increase in global air traffic has amplified contamination risks by airborne flu-like diseases and terrorist threats involving the onboard release of noxious materials. In particular, passengers moving through a ventilated cabin may transport infectious pathogens in their wake. This paper presents an experimental investigation of the wake produced by a bluff body driven through a steady recirculating flow. Data were obtained in a water facility using particle image velocimetry and planar laser induced fluorescence. Ventilation attenuated the downward convection of counter-rotating vortices produced near the free-end corners of the body and decoupled the downwash mechanism from forward entrainment, creating stagnant contaminant regions.
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Affiliation(s)
- Stephane B. Poussou
- School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907 USA
| | - Michael W. Plesniak
- Department of Mechanical and Aerospace Engineering, The George Washington University, 801 22nd Street, N.W., Washington, DC 20052 USA
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20
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Chaturvedi AK. Aerospace toxicology overview: aerial application and cabin air quality. REVIEWS OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2011; 214:15-40. [PMID: 21913123 DOI: 10.1007/978-1-4614-0668-6_2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Aerospace toxicology is a rather recent development and is closely related to aerospace medicine. Aerospace toxicology can be defined as a field of study designed to address the adverse effects of medications, chemicals, and contaminants on humans who fly within or outside the atmosphere in aviation or on space flights. The environment extending above and beyond the surface of the Earth is referred to as aerospace. The term aviation is frequently used interchangeably with aerospace. The focus of the literature review performed to prepare this paper was on aerospace toxicology-related subject matters, aerial application and aircraft cabin air quality. Among the important topics addressed are the following: · Aerial applications of agricultural chemicals, pesticidal toxicity, and exposures to aerially applied mixtures of chemicals and their associated formulating solvents/surfactants The safety of aerially encountered chemicals and the bioanalytical methods used to monitor exposures to some of them · The presence of fumes and smoke, as well as other contaminants that may generally be present in aircraft/space vehicle cabin air · And importantly, the toxic effects of aerially encountered contaminants, with emphasis on the degradation products of oils, fluids, and lubricants used in aircraft, and finally · Analytical methods used for monitoring human exposure to CO and HCN are addressed in the review, as are the signs and symptoms associated with exposures to these combustion gases. Although many agricultural chemical monitoring studies have been published, few have dealt with the occurrence of such chemicals in aircraft cabin air. However, agricultural chemicals do appear in cabin air; indeed, attempts have been made to establish maximum allowable concentrations for several of the more potentially toxic ones that are found in aircraft cabin air. In this article, I emphasize the need for precautionary measures to be taken to minimize exposures to aerially encountered chemicals, or aircraft cabin air contaminants and point out the need for future research to better address toxicological evaluation of aircraft-engine oil additives.
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Affiliation(s)
- Arvind K Chaturvedi
- Bioaeronautical Sciences Research Laboratory (AAM-610), Aerospace Medical Research Division, Civil Aerospace Medical Institute, Federal Aviation Administration, US Department of Transportation, Oklahoma City, OK 73125-5066, USA.
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21
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Kawasaki T, Kyotani T, Ushiogi T, Izumi Y, Lee H, Hayakawa T. Distribution and Identification of Airborne Fungi in Railway Stations in Tokyo, Japan. J Occup Health 2010; 52:186-93. [DOI: 10.1539/joh.o9022] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
| | | | | | - Yasuhiko Izumi
- Architecture Laboratory, Railway Technical Research InstituteJapan
| | - Hunjun Lee
- Hygiene and Microbiology Research CenterJapan
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22
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Monitoring Microbial Populations on Wide-Body Commercial Passenger Aircraft. ACTA ACUST UNITED AC 2008; 52:139-49. [DOI: 10.1093/annhyg/mem068] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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23
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La Duc MT, Stuecker T, Venkateswaran K. Molecular bacterial diversity and bioburden of commercial airliner cabin air. Can J Microbiol 2008; 53:1259-71. [PMID: 18026220 DOI: 10.1139/w07-093] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Culture-independent, biomarker-targeted bacterial enumeration and identification strategies were employed to estimate total bacterial burden and diversity within the cabin air of commercial airliners. Samples from each of 4 flights on 2 commercial carriers were collected via air-impingement. The total viable microbial population ranged from below detection limits to 4.1 x 10(6) cells/m(3) of air, as assessed by the ATP assay. A gradual accumulation of microbes was observed from the time of passenger boarding through mid-flight, followed by a sharp decline in bacterial abundance and viability from the initiation of descent through landing. Representatives of the alpha-, beta-, and gamma-Proteobacteria, as well as Gram-positive bacteria, were isolated in varying abundance. Neisseria meningitidis rRNA gene sequences were retrieved in great abundance from Airline A followed by Streptococcus oralis/mitis sequences. Pseudomonas synxantha sequences dominated Airline B clone libraries, followed by those of N. meningitidis and S. oralis/mitis. The cabin air samples examined herein housed low bacterial diversity and were often dominated by a particular subset of bacteria: opportunistic pathogenic inhabitants of the human respiratory tract and oral cavity.
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Affiliation(s)
- Myron T La Duc
- Biotechnology and Planetary Protection Group, M/S 89, Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA
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24
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Osman S, La Duc MT, Dekas A, Newcombe D, Venkateswaran K. Microbial burden and diversity of commercial airline cabin air during short and long durations of travel. ISME JOURNAL 2008; 2:482-97. [PMID: 18256704 PMCID: PMC7099242 DOI: 10.1038/ismej.2008.11] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Total microbial burden and diversity associated with commercial airliner cabin air was assessed by molecular methods in 125 air samples from the business-class sections of 16 domestic and international flights. Viable microbial burden within these cabin air parcels constituted only 1–10% of the total microbial population and ranged from below detection limits to 1.2 × 104 cells m–3 as determined with a validated ATP-based technology. Cultivable bacterial diversity was almost entirely limited to Gram-positive bacteria such as Staphylococcus and Bacillus. In contrast, cloning and sequencing 16S rRNA gene directly from the samples without cultivation indicated a significantly broader diversity, as sequences representing more than 100 species, and encompassing 12 classes of bacteria, were retrieved in varying abundance. Sequences of proteobacterial and Gram-positive lineage were retrieved most frequently (58% and 31% of all clone sequences, respectively), with Gram-positive and α-proteobacterial sequences dominating international flight samples and β- and γ-proteobacterial sequences comprising the largest portion of those retrieved from domestic flights. Significant differences in bacterial load and diversity were noted between samples obtained on domestic and international flights. The disparities observed in microbial abundance and diversity further underscore the immense value of state-of-the art molecular assays in augmenting traditional culture-based techniques.
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Affiliation(s)
- Shariff Osman
- California Institute of Technology, Pasadena, CA, USA
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25
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Concentrations of Selected Chemical Species in the Airliner Cabin Environment. ACTA ACUST UNITED AC 2008. [DOI: 10.1520/jai101639] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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26
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Martinez L, Blanc L, Nunn P, Raviglione M. Tuberculosis and air travel: WHO guidance in the era of drug-resistant TB. Travel Med Infect Dis 2007; 6:177-81. [PMID: 18571104 DOI: 10.1016/j.tmaid.2007.10.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2007] [Accepted: 10/15/2007] [Indexed: 10/22/2022]
Abstract
Air travel provides opportunities for infectious diseases to spread rapidly between countries and continents. There may be a potential risk of transmission during the flight, notably with airborne and droplet-borne respiratory infections. Seven episodes of potential transmission of TB infection during air travel reported in 1992--1994 caused widespread concern. Contact investigations revealed evidence of transmission of infection in two instances but active TB disease was not found in any of the infected individuals, or in subsequently published cases. In recent years, multidrug-resistant TB (MDR-TB) has become an increasingly important public health problem in many countries, exacerbated by the emergence of extensively drug-resistant TB (XDR-TB). The potential risk of transmission of particularly dangerous forms of TB requires renewed vigilance. The revised International Health Regulations (1995) include new provisions which are relevant to the transmission of TB on aircraft. WHO published a second edition of Tuberculosis and air travel: guidelines for prevention and control in 2006, providing updated information and specific guidance for passengers and crew, physicians, public health authorities and airline companies. Following several recent incidents involving MDR-TB and XDR-TB in airline passengers, the 2006 recommendations will be amplified in the light of experience gained and the evolving epidemiological situation.
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Affiliation(s)
- Lindsay Martinez
- Stop TB Department, World Health Organization, 1211 Geneva 27, Switzerland.
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27
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Abstract
Passenger well-being is influenced by cabin environmental conditions which interact with individual passenger characteristics like age and health conditions. Cabin environment is composed of different aspects, some of which have a direct influence on gastrointestinal functions and may directly generate nausea, such as cabin pressure, oxygen saturation, and motion or vibration. For example, it has been shown that available cabin pressure during normal flight altitude can significantly inhibit gastric emptying and induce dyspepsia-like symptoms when associated with a fibre-rich meal. Other aspects of the cabin environment such as space and variability of seating, air quality, and noise, also have been shown to modulate (reduce or increase) discomfort and nausea during flights. Individual passenger characteristics and health status also have been demonstrated to increase vulnerability to adverse health outcomes and discomfort.
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Affiliation(s)
- H Hinninghofen
- University Hospitals Tübingen, Internal Medicine VI, Psychosomatic Medicine and Psychotherapy, Fronsbergstrasse 23, D-72070 Tübingen, Germany.
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28
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Hocking M. Airplanes and Infectious Disease. THE HANDBOOK OF ENVIRONMENTAL CHEMISTRY 2005. [PMCID: PMC7120329 DOI: 10.1007/b107241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Air travel is associated with crowded conditions that can facilitate the transmission of airborne
infectious diseases. The risk of contracting such diseases depends on the presence of an infected
person who is shedding infectious particles and sufficient exposure of a sensitive person to achieve
an adequate dose to cause disease. Proximity to the infectious person and the length of time spent
near the person are the most important risks for contracting a disease. Ventilation patterns play
a lesser role in disease transmission. Well-documented outbreaks of influenza, severe acute respiratory
syndrome (SARS), and tuberculosis have occurred. Other common respiratory illnesses have probably
also been spread via aircraft, but outbreaks remain unrecognized. Research on the spread of infectious
disease in aircraft has focused on sampling for microorganisms in air (which has little relevance),
and on the development of models to predict the risks for specific diseases.
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29
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Aircraft Environmental Control Systems. THE HANDBOOK OF ENVIRONMENTAL CHEMISTRY 2005. [PMCID: PMC7120822 DOI: 10.1007/b107234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The external environment at 41000 ft (12500 m), a typical cruise altitude for
modern civil aircraft, is hostile to human life. Aircraft environmental control systems are designed
to ensure the survival of the aircraft occupants as well as providing them with a comfortable
atmosphere. Major design drivers for the environmental control system are thermal comfort, pressurisation
and cabin air quality. However, these parameters cannot be considered independently. They interact
between themselves and with other parameters, which may or may not be controllable by the system designer.
These interactions occur in a highly complex manner. Research has led to a good understanding
of the basic functions to allow safe and comfortable aircraft environmental conditions. Future research
efforts will be increasingly focussed on identifying and elaborating the interdependency of factors
in order to further enhance the aircraft cabin environment.
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30
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Abstract
An increasing number of individuals undertake air travel annually. Issues regarding cabin air quality and the potential risks of transmission of respiratory infections during flight have been investigated and debated previously, but, with the advent of severe acute respiratory syndrome and influenza outbreaks, these issues have recently taken on heightened importance. Anecdotally, many people complain of respiratory symptoms following air travel. However, studies of ventilation systems and patient outcomes indicate the spread of pathogens during flight occurs rarely. In the present review, aspects of the aircraft cabin environment that affect the likelihood of transmission of respiratory pathogens on airplanes are outlined briefly and evidence for the occurrence of outbreaks of respiratory illness among airline passengers are reviewed. (Intern Med J 2005; 35: 50–55)
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Affiliation(s)
- K Leder
- Victorian Infections Diseases Service, Royal Melbourne Hospital, Melbourne, Victoria, Australia.
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31
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Nagda NL, Rector HE. A critical review of reported air concentrations of organic compounds in aircraft cabins. INDOOR AIR 2003; 13:292-301. [PMID: 12950593 DOI: 10.1034/j.1600-0668.2003.00202.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
This paper presents a review and assessment of aircraft cabin air quality studies with measured levels of volatile and semivolatile organic compounds (VOCs and SVOCs). VOC and SVOC concentrations reported for aircraft cabins are compared with those reported for residential and office buildings and for passenger compartments of other types of transportation. An assessment of measurement technologies and quality assurance procedures is included. The six studies reviewed in the paper range in coverage from two to about 30 flights per study. None of the monitored flights included any unusual or episodic events that could affect cabin air quality. Most studies have used scientifically sound methods for measurements. Study results indicate that under routine aircraft operations, contaminant levels in aircraft cabins are similar to those in residential and office buildings, with two exceptions: (1). levels of ethanol and acetone, indicators of bioeffluents and chemicals from consumer products are higher in aircraft than in home or office environments, and (2). levels of certain chlorinated hydrocarbons and fuel-related contaminants are higher in residential/office buildings than in aircraft. Similarly, ethanol and acetone levels are higher in aircraft than in other transportation modes but the levels of some pollutants, such as m-/p-xylenes, tend to be lower in aircraft.
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Affiliation(s)
- N L Nagda
- ENERGEN Consulting, Inc, Germantown, MD 20874, USA.
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Lindgren T, Norbäck D. Cabin air quality: indoor pollutants and climate during intercontinental flights with and without tobacco smoking. INDOOR AIR 2002; 12:263-272. [PMID: 12532758 DOI: 10.1034/j.1600-0668.2002.01121.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The aim was to determine cabin air quality and in-flight exposure for cabin attendants of specific pollutants during intercontinental flights. Measurements of air humidity, temperature, carbon dioxide (CO2), respirable particles, ozone (O3), nitrogen dioxide (NO2) and formaldehyde were performed during 26 intercontinental flights with Boeing 767-300 with and without tobacco smoking onboard. The mean temperature in cabin was 22.2 degrees C (range 17.4-26.8 degrees C), and mean relative air humidity was 6% (range 1-27%). The CO2 concentration during cruises was below the recommended limit of 1000 ppm during 96% of measured time. Mean indoor concentration of NO2 and O3, were 14.1 and 19.2 micrograms/m3, with maximum values of 37 and 66 micrograms/m3, respectively. The concentration of formaldehyde was below the detection limit (< 5 micrograms/m3), in most samples (77%), and the maximum value was 15 micrograms/m3. The mean concentration of respirable particles in the rear part of the aircraft (AFT galley area) was much higher (49 micrograms/m3) during smoking as compared with non-smoking conditions (3 micrograms/m3) (P < 0.001), with maximum values of 253 and 7 micrograms/m3. In conclusion, air humidity is very low on intercontinental flights, and the large variation of temperature shows a need for better temperature control. Tobacco smoking onboard leads to a significant pollution of respirable particles, particularly in the rear part of the cabin. The result supports the view that despite the high air exchange rate and efficient air filtration, smoking in commercial aircraft leads to a significant pollution and should be prohibited.
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Affiliation(s)
- T Lindgren
- Department of Medical Sciences/Occupational and Environmental Medicine, Uppsala University Hospital, Uppsala, Sweden.
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Hocking MB. Passenger aircraft cabin air quality: trends, effects, societal costs, proposals. CHEMOSPHERE 2000; 41:603-615. [PMID: 10819229 DOI: 10.1016/s0045-6535(99)00537-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
As aircraft operators have sought to substantially reduce propulsion fuel cost by flying at higher altitudes, the energy cost of providing adequate outside air for ventilation has increased. This has lead to a significant decrease in the amount of outside air provided to the passenger cabin, partly compensated for by recirculation of filtered cabin air. The purpose of this review paper is to assemble the available measured air quality data and some calculated estimates of the air quality for aircraft passenger cabins to highlight the trend of the last 25 years. The influence of filter efficiencies on air quality, and a few medically documented and anecdotal cases of illness transmission aboard aircraft are discussed. Cost information has been collected from the perspective of both the airlines and passengers. Suggestions for air quality improvement are given which should help to result in a net, multistakeholder savings and improved passenger comfort.
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Affiliation(s)
- M B Hocking
- Department of Chemistry, University of Victoria, BC, Canada.
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Shiloah J, Patters MR, Waring MB. The prevalence of pathogenic periodontal microflora in healthy young adult smokers. J Periodontol 2000; 71:562-7. [PMID: 10807119 DOI: 10.1902/jop.2000.71.4.562] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Smoking is a major risk factor in periodontitis, although the mechanisms of its effects are not well understood. The overall goal of this clinical study was to determine if smoking enhances the colonization of the oral cavity by pathogenic bacteria in a periodontitis-free population. The prevalence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum, Campylobacter rectus, Eikenella corrodens, Bacteroides forsythus, and Treponema denticola was investigated in 25 smokers and 25 non-smokers by using DNA probes. METHODS The subjects were 21 to 35 years of age with a healthy periodontium or slight gingivitis and were systemically healthy. The test group included subjects who had a minimum of a 1.5 pack-year history of smoking, while the control subjects never smoked. Subgingival plaque samples were taken by paper point following the assessment of multiple clinical parameters. RESULTS This investigation showed: 1) no statistically significant differences were noted in any clinical parameter measured between the groups; 2) of the 8 subjects who were infected by at least 1 tested pathogen, seven were smokers (P= 0.02); 3) infected smokers had a 15.7+/-3.5 pack-year history and smoked a mean of 27+/-5 cigarettes/day versus 4.4+/-0.8 pack years and 15+/-1 cigarettes/day for the non-infected smokers (P = 0.0001 and P = 0.004); and 4) smokers were 18 times more likely to exhibit the presence of pathogens than non-smokers. CONCLUSIONS These data indicate that the prevalence of colonization of the sulcus by pathogenic bacterial species in periodontitis-free individuals is related to the quantity and duration of cigarette smoking.
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Affiliation(s)
- J Shiloah
- Department of Periodontology, College of Dentistry, The University of Tennessee, Memphis 38163, USA.
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Hocking MB. Passenger aircraft cabin air quality: Trends, effects, societal costs, proposals. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2000; 7:173-174. [PMID: 19104880 DOI: 10.1007/bf02987740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Affiliation(s)
- M B Hocking
- IIIEE, Lund University, P.O. Box 196, S-221 00, Lund, Sweden
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Abstract
Sixteen flights had been investigated for indoor air quality (IAQ) on Cathay Pacific aircraft from June 1996 to August 1997. In general, the air quality on Cathay Pacific aircraft was within relevant air quality standards because the average age of aircraft was less than 2 years. Carbon dioxide (CO2) levels on all flights measured were below the Federal Aviation Administration (FAA) standard (30,000 ppm). The CO2 level was substantially higher during boarding and de-boarding than cruise due to low fresh air supply. Humidity on the aircraft was low, especially for long-haul flights. Minimum humidity during cruise was below the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) minimum humidity standard (20%). The average temperature was within a comfortable temperature range of 23 +/- 2 degrees C. The vertical temperature profile on aircraft was uniform and below the International Standard Organization (ISO) standard. Carbon monoxide levels were below the FAA standard (50 ppm). Trace amount of ozone detected ranged from undetectable to 90 ppb, which was below the FAA standard. Particulate level was low for most non-smoking flights, but peaks were observed during boarding and de-boarding. The average particulate level in smoking flights (138 micrograms/m3) was higher than non-smoking flights (7.6 micrograms/m3). The impact on IAQ by switching from low-mode to high-mode ventilation showed a reduction in CO2 levels, temperature, and relative humidity.
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Affiliation(s)
- S C Lee
- Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong.
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