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Riederer AM, Krenz JE, Tchong-French MI, Torres E, Perez A, Younglove LR, Jansen KL, Hardie DC, Farquhar SA, Sampson PD, Metwali N, Thorne PS, Karr CJ. Effectiveness of portable HEPA air cleaners on reducing indoor endotoxin, PM 10, and coarse particulate matter in an agricultural cohort of children with asthma: A randomized intervention trial. INDOOR AIR 2021; 31:1926-1939. [PMID: 34288127 PMCID: PMC8577577 DOI: 10.1111/ina.12858] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 04/05/2021] [Accepted: 05/02/2021] [Indexed: 06/13/2023]
Abstract
We conducted a randomized trial of portable HEPA air cleaners in the homes of children age 6-12 years with asthma in the Yakima Valley, Washington. All families received asthma education while intervention families also received two HEPA cleaners (child's bedroom, living room). We collected 14-day integrated samples of endotoxin in settled dust and PM10 and PM10-2.5 in the air of the children's bedrooms at baseline and one-year follow-up, and used linear regression to compare follow-up levels, adjusting for baseline. Seventy-one families (36 HEPA, 35 control) completed the study. Baseline geometric mean (GSD) endotoxin loadings were 1565 (6.3) EU/m2 and 2110 (4.9) EU/m2 , respectively, in HEPA vs. control homes while PM10 and PM10-2.5 were 22.5 (1.9) μg/m3 and 9.5 (2.9) μg/m3 , respectively, in HEPA homes, and 19.8 (1.8) μg/m3 and 7.7 (2.0) μg/m3 , respectively, in control homes. At follow-up, HEPA families had 46% lower (95% CI, 31%-57%) PM10 on average than control families, consistent with prior studies. In the best-fit heterogeneous slopes model, HEPA families had 49% (95% CI, 6%-110%) and 89% lower (95% CI, 28%-177%) PM10-2.5 at follow-up, respectively, at 50th and 75th percentile baseline concentrations. Endotoxin loadings did not differ significantly at follow-up (4% lower, HEPA homes; 95% CI, -87% to 50%).
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Affiliation(s)
- Anne M. Riederer
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - Jennifer E. Krenz
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - Maria I. Tchong-French
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - Elizabeth Torres
- Northwest Communities Education Center, Radio KDNA, Granger, WA, USA
| | - Adriana Perez
- Yakima Valley Farm Workers Clinic, Toppenish, WA, USA
| | - Lisa R. Younglove
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - Karen L. Jansen
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - David C. Hardie
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - Stephanie A. Farquhar
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - Paul D. Sampson
- Department of Biostatistics, University of Washington, Seattle, WA, USA
| | - Nervana Metwali
- Department of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, IA, USA
| | - Peter S. Thorne
- Department of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, IA, USA
| | - Catherine J. Karr
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
- Department of Pediatrics, University of Washington, Seattle, WA, USA
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Kabir AF, Ng CFS, Yasumoto S, Hayashi T, Watanabe C. Effect of Ambient Temperature on Daily Nebulized Asthma Hospital Visits in a Tropical City of Dhaka, Bangladesh. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18030890. [PMID: 33498592 PMCID: PMC7908622 DOI: 10.3390/ijerph18030890] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 01/14/2021] [Accepted: 01/19/2021] [Indexed: 11/19/2022]
Abstract
The acute effect of temperature on asthma morbidity in Bangladesh is not well understood. As climate varies extensively in different parts of the world, the relation between temperature and asthma might also differ. We investigated the association between temperature and asthma-related hospital visits in the tropical city of Dhaka. We analyzed information from a total of 5989 asthma patients who received ambulatory care in the form of nebulized medication at the National Asthma Center in Mohakhali, Dhaka from February to November 2013. A time-stratified case-crossover study was conducted to estimate the effect of daily temperature, with consideration of delayed effects and possible confounders such as relative humidity and political strikes. An inverse association was observed between temperature and the number of hospital visits. The effect was delayed for approximately a week. A degree centigrade decrease in mean temperature (averaged across lags 0-6) was associated with an increase of approximately 4.5% (95% CI 1.5, 7.5) in all asthma visits. The association was evident in adult males but marginal in elderly males. A positive association (lag 0) was observed among adult females, whereas no association was observed among children. Strikes significantly modified the effect among the elderly. Findings suggest temperature declines affect asthma outcomes in a warm climate, and this effect can be delayed and vary by sex and age group.
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Affiliation(s)
- Ayesha Ferdosi Kabir
- Department of Human Ecology, School of International Health, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan; (A.F.K.); (S.Y.); (C.W.)
| | - Chris Fook Sheng Ng
- School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki 852-8523, Japan
- Correspondence:
| | - Shinya Yasumoto
- Department of Human Ecology, School of International Health, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan; (A.F.K.); (S.Y.); (C.W.)
| | - Taiichi Hayashi
- Center for Southeast Asian Studies, Kyoto University, Kyoto 606-8501, Japan;
| | - Chiho Watanabe
- Department of Human Ecology, School of International Health, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan; (A.F.K.); (S.Y.); (C.W.)
- National Institute for Environmental Studies, Tsukuba, Ibaraki 305-0053, Japan
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Yen YC, Yang CY, Wang TN, Yen PC, Ho CK, Mena KD, Lee TC, Chen KS, Lin YC, Chen PS. Household airborne endotoxin associated with asthma and allergy in elementary school-age children: a case-control study in Kaohsiung, Taiwan. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:19502-19509. [PMID: 32212084 PMCID: PMC7244453 DOI: 10.1007/s11356-020-07899-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 01/27/2020] [Indexed: 06/10/2023]
Abstract
To evaluate the association between the presence of asthma and allergy, and airborne endotoxin in homes of school-age children in Kaohsiung City, Taiwan, with a case-control study design by matching the age and class exposure. Data collection of home visits included an interviewer-administered questionnaire and air sampling of participants' homes for endotoxin, bacteria, and fungi, as well as temperature and relative humidity measurements. Endotoxin was detected in all air samples with a median value of 0.67 EU m-3. In the adjusted logistic regression model, household airborne endotoxin was associated with higher prevalence of asthma and allergy; OR = 4.88 (95% CI 1.16-20.55) for Q3 (between 0.67 and 1.97 EU m -3) vs. Q1 (< 0.31 EU m -3), with statistical significance. Airborne fungi were associated with higher prevalence of asthma and allergy; OR = 4.47 (95% CI 1.13-17.69) for Q3 (between 314 and 699 CFU m -3) vs. Q1 (< 159 CFU m -3) in adjusted logistic regression models. Airborne endotoxin and fungi were significantly associated with children's asthma and allergy.
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Affiliation(s)
- Yu-Chuan Yen
- Department of Public Health, College of Health Science, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chun-Yuh Yang
- Department of Public Health, College of Health Science, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Tsu-Nai Wang
- Department of Public Health, College of Health Science, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Pei-Chun Yen
- Department of Public Health, College of Health Science, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chi-Kung Ho
- Department of Public Health, College of Health Science, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Kristina D Mena
- Epidemiology, Human Genetics, and Environmental Sciences, School of Public Health, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Tzu-Chi Lee
- Department of Public Health, College of Health Science, Kaohsiung Medical University, Kaohsiung, Taiwan
- Department of Health Promotion and Health Education, National Taiwan Normal University, Taipei, Taiwan
| | - Kang-Shin Chen
- Institute of Environmental Engineering, College of Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan
| | - Yuan-Chung Lin
- Institute of Environmental Engineering, College of Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan
| | - Pei-Shih Chen
- Department of Public Health, College of Health Science, Kaohsiung Medical University, Kaohsiung, Taiwan.
- Institute of Environmental Engineering, College of Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan.
- Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
- Research Center for Environmental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
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Haines SR, Adams RI, Boor BE, Bruton TA, Downey J, Ferro AR, Gall E, Green BJ, Hegarty B, Horner E, Jacobs DE, Lemieux P, Misztal PK, Morrison G, Perzanowski M, Reponen T, Rush RE, Virgo T, Alkhayri C, Bope A, Cochran S, Cox J, Donohue A, May AA, Nastasi N, Nishioka M, Renninger N, Tian Y, Uebel-Niemeier C, Wilkinson D, Wu T, Zambrana J, Dannemiller KC. Ten questions concerning the implications of carpet on indoor chemistry and microbiology. BUILDING AND ENVIRONMENT 2019; 170:1-16. [PMID: 32055099 PMCID: PMC7017391 DOI: 10.1016/j.buildenv.2019.106589] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Carpet and rugs currently represent about half of the United States flooring market and offer many benefits as a flooring type. How carpets influence our exposure to both microorganisms and chemicals in indoor environments has important health implications but is not well understood. The goal of this manuscript is to consolidate what is known about how carpet impacts indoor chemistry and microbiology, as well as to identify the important research gaps that remain. After describing the current use of carpet indoors, questions focus on five specific areas: 1) indoor chemistry, 2) indoor microbiology, 3) resuspension and exposure, 4) current practices and future needs, and 5) sustainability. Overall, it is clear that carpet can influence our exposures to particles and volatile compounds in the indoor environment by acting as a direct source, as a reservoir of environmental contaminants, and as a surface supporting chemical and biological transformations. However, the health implications of these processes are not well known, nor how cleaning practices could be optimized to minimize potential negative impacts. Current standards and recommendations focus largely on carpets as a primary source of chemicals and on limiting moisture that would support microbial growth. Future research should consider enhancing knowledge related to the impact of carpet in the indoor environment and how we might improve the design and maintenance of this common material to reduce our exposure to harmful contaminants while retaining the benefits to consumers.
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Affiliation(s)
- Sarah R. Haines
- Department of Civil, Environmental & Geodetic Engineering, College of Engineering, Environmental Health Sciences, College of Public Health, and Environmental Sciences Graduate Program, The Ohio State University, Columbus, OH, 43210, USA
| | - Rachel I. Adams
- Plant & Microbial Biology, University of California, Berkeley, CA, 94720, USA
| | - Brandon E. Boor
- Lyles School of Civil Engineering, Purdue University, West Lafayette, IN, 47907, USA
| | | | - John Downey
- Cleaning Industry Research Institute, Granville, OH, 43023, USA
| | - Andrea R. Ferro
- Department of Civil and Environmental Engineering, Clarkson University, Potsdam, NY, 13699, USA
| | - Elliott Gall
- Department of Mechanical and Materials Engineering, Portland State University, Portland, OR, 97201, USA
| | - Brett J. Green
- Allergy and Clinical Immunology Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Morgantown, WV, 26505, USA
| | - Bridget Hegarty
- Civil and Environmental Engineering, College of Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Elliott Horner
- UL Environment and Sustainability, Marietta, GA, 30067, USA
| | - David E. Jacobs
- National Center for Healthy Housing, Columbia, MD, 21044, USA
| | - Paul Lemieux
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, 27711, USA
| | - Pawel K. Misztal
- Department of Civil, Architectural and Environmental Engineering, University of Texas at Austin, Austin, TX, 78712, USA
| | - Glenn Morrison
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Matthew Perzanowski
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, 10032, USA
| | - Tiina Reponen
- Division of Environmental and Industrial Hygiene, Department of Environmental Health, College of Medicine, University of Cincinnati, Cincinnati, OH, 45220, USA
| | - Rachael E. Rush
- Allergy and Clinical Immunology Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Morgantown, WV, 26505, USA
- Department of Microbiology, Immunology, and Cell Biology, West Virginia University, Morgantown, WV, 26506, USA
| | - Troy Virgo
- Shaw Industries, Inc., Dalton, GA, 30722-2128, USA
| | - Celine Alkhayri
- Department of Civil, Environmental & Geodetic Engineering, College of Engineering, The Ohio State University, Columbus, OH, 43210, USA
| | - Ashleigh Bope
- Department of Civil, Environmental & Geodetic Engineering, College of Engineering, Environmental Health Sciences, College of Public Health, and Environmental Sciences Graduate Program, The Ohio State University, Columbus, OH, 43210, USA
| | - Samuel Cochran
- Department of Civil, Environmental & Geodetic Engineering, College of Engineering, Environmental Health Sciences, College of Public Health, and Environmental Sciences Graduate Program, The Ohio State University, Columbus, OH, 43210, USA
| | - Jennie Cox
- Division of Environmental and Industrial Hygiene, Department of Environmental Health, College of Medicine, University of Cincinnati, Cincinnati, OH, 45220, USA
| | - Allie Donohue
- Department of Civil, Environmental & Geodetic Engineering, College of Engineering, The Ohio State University, Columbus, OH, 43210, USA
| | - Andrew A. May
- Department of Civil, Environmental & Geodetic Engineering, College of Engineering, The Ohio State University, Columbus, OH, 43210, USA
| | - Nicholas Nastasi
- Department of Civil, Environmental & Geodetic Engineering, College of Engineering, Environmental Health Sciences, College of Public Health, and Environmental Sciences Graduate Program, The Ohio State University, Columbus, OH, 43210, USA
| | - Marcia Nishioka
- Department of Civil, Environmental & Geodetic Engineering, College of Engineering, The Ohio State University, Columbus, OH, 43210, USA
| | - Nicole Renninger
- Department of Civil, Environmental & Geodetic Engineering, College of Engineering, The Ohio State University, Columbus, OH, 43210, USA
| | - Yilin Tian
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA, 94720, USA
| | - Christina Uebel-Niemeier
- Division of Environmental and Industrial Hygiene, Department of Environmental Health, College of Medicine, University of Cincinnati, Cincinnati, OH, 45220, USA
| | | | - Tianren Wu
- Lyles School of Civil Engineering, Purdue University, West Lafayette, IN, 47907, USA
| | - Jordan Zambrana
- Indoor Environments Division, Office of Air and Radiation, U.S. Environmental Protection Agency, Washington, DC, 20460, USA
| | - Karen C. Dannemiller
- Department of Civil, Environmental & Geodetic Engineering, College of Engineering, and Environmental Health Sciences, College of Public Health, The Ohio State University, Columbus, OH, 43210, USA
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5
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Järvi K, Hyvärinen A, Täubel M, Karvonen AM, Turunen M, Jalkanen K, Patovirta R, Syrjänen T, Pirinen J, Salonen H, Nevalainen A, Pekkanen J. Microbial growth in building material samples and occupants' health in severely moisture-damaged homes. INDOOR AIR 2018; 28:287-297. [PMID: 29151276 DOI: 10.1111/ina.12440] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 11/09/2017] [Indexed: 06/07/2023]
Abstract
There is no commonly approved approach to detect and quantify the health-relevant microbial exposure in moisture-damaged buildings. In 39 single-family homes with severe moisture damage, we studied whether concentrations of viable microbes in building material samples are associated with health among 71 adults and 68 children, and assessed with symptoms questionnaires, exhaled NO, and peak expiratory flow (PEF) variability. Symptoms were grouped into three scores: upper respiratory symptoms, lower respiratory symptoms, and general symptoms. The homes were divided into three groups based on viable counts of fungi, actinomycetes, and total bacteria cultivated from building material samples. Highest group of actinomycete counts was associated with more general symptoms, worse perceived health, and higher daily PEF variability (aOR 12.51; 1.10-141.90 as compared to the lowest group) among adults, and with an increase in lower respiratory symptoms in children, but the confidence intervals were wide. We observed significant associations of fungal counts and total microbial score with worse perceived health in adults. No associations with exhaled NO were observed.
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Affiliation(s)
- K Järvi
- Environmental Health Unit, National Institute for Health and Welfare, Kuopio, Finland
- School of Engineering, Aalto University, Espoo, Finland
| | - A Hyvärinen
- Environmental Health Unit, National Institute for Health and Welfare, Kuopio, Finland
| | - M Täubel
- Environmental Health Unit, National Institute for Health and Welfare, Kuopio, Finland
| | - A M Karvonen
- Environmental Health Unit, National Institute for Health and Welfare, Kuopio, Finland
| | - M Turunen
- Environmental Health Unit, National Institute for Health and Welfare, Kuopio, Finland
| | - K Jalkanen
- Environmental Health Unit, National Institute for Health and Welfare, Kuopio, Finland
| | - R Patovirta
- Department of Respiratory Medicine, Kuopio University Hospital, Kuopio, Finland
| | - T Syrjänen
- The Organisation for Respiratory Health in Finland, Helsinki, Finland
| | - J Pirinen
- The Organisation for Respiratory Health in Finland, Helsinki, Finland
- Ministry of Environment, Helsinki, Finland
| | - H Salonen
- School of Engineering, Aalto University, Espoo, Finland
| | - A Nevalainen
- Environmental Health Unit, National Institute for Health and Welfare, Kuopio, Finland
| | - J Pekkanen
- Environmental Health Unit, National Institute for Health and Welfare, Kuopio, Finland
- Department of Public Health, University of Helsinki, Helsinki, Finland
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6
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Yoda Y, Tamura K, Shima M. Airborne endotoxin concentrations in indoor and outdoor particulate matter and their predictors in an urban city. INDOOR AIR 2017; 27:955-964. [PMID: 28161889 DOI: 10.1111/ina.12370] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 01/28/2017] [Indexed: 06/06/2023]
Abstract
Endotoxins are an important biological component of particulate matter and have been associated with adverse effects on human health. There have been some recent studies on airborne endotoxin concentrations. We collected fine (PM2.5 ) and coarse (PM10-2.5 ) particulate matter twice on weekdays and weekends each for 48 hour, inside and outside 55 homes in an urban city in Japan. Endotoxin concentrations in both fractions were measured using the kinetic Limulus Amebocyte Lysate assay. The relationships between endotoxin concentrations and household characteristics were evaluated for each fraction. Both indoor and outdoor endotoxin concentrations were higher in PM2.5 than in PM10-2.5 . In both PM2.5 and PM10-2.5 , indoor endotoxin concentrations were higher than outdoor concentrations, and the indoor endotoxin concentrations significantly correlated with outdoor concentrations in each fraction (R2 =0.458 and 0.198, respectively). Indoor endotoxin concentrations in PM2.5 were significantly higher in homes with tatami or carpet flooring and in homes with pets, and lower in homes that used air purifiers. Indoor endotoxin concentrations in PM10-2.5 were significantly higher in homes with two or more children and homes with tatami or carpet flooring. These results showed that the indoor endotoxin concentrations were associated with the household characteristics in addition to outdoor endotoxin concentrations.
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Affiliation(s)
- Y Yoda
- Department of Public Health, Hyogo College of Medicine, Nishinomiya, Japan
| | - K Tamura
- Center for Health and Environmental Risk Research, National Institute for Environmental Studies, Tsukuba, Japan
| | - M Shima
- Department of Public Health, Hyogo College of Medicine, Nishinomiya, Japan
- Hyogo Regional Center of Japan Environment and Children's Study, Hyogo College of Medicine, Nishinomiya, Japan
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7
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McNamara ML, Thornburg J, Semmens EO, Ward TJ, Noonan CW. Reducing indoor air pollutants with air filtration units in wood stove homes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 592:488-494. [PMID: 28320525 PMCID: PMC6394836 DOI: 10.1016/j.scitotenv.2017.03.111] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 03/10/2017] [Accepted: 03/11/2017] [Indexed: 05/29/2023]
Abstract
BACKGROUND Biomass burning has been shown to be a major source of poor indoor air quality (IAQ) in developing and higher income countries across the world. Specifically, wood burning for cooking and heating contributes to high indoor concentrations of fine (particles with aerodynamic diameters<2.5μm; PM2.5) and coarse (particles with aerodynamic diameters <10μm and >2.5μm; PMc) particulate matter. Endotoxin, predominantly found within the coarse fraction of airborne particulate matter, is associated with proinflammatory effects and adverse outcomes among susceptible populations. The aim of this study was to assess the efficacy of air filter interventions in reducing indoor PM2.5, PMc, and PMc-associated endotoxin concentrations in homes using a wood stove for primary heating. RESULTS Homes (n=48) were randomized to receive in-room air filtration units with either a high efficiency filter (i.e. active) or a lower efficiency fiberglass filter (i.e., placebo). The active filter intervention showed a 66% reduction in indoor PM2.5 concentrations (95% CI: 42.2% to 79.7% reduction) relative to the placebo intervention. Both the active and the placebo filters were effective in substantially reducing indoor concentrations of PMc (63.3% and 40.6% average reduction for active and placebo filters, respectively) and PMc-associated endotoxin concentrations (91.8% and 80.4% average reductions, respectively). CONCLUSIONS These findings support the use of high efficiency air filtration units for reducing indoor PM2.5 in homes using a wood stove for primary heating. We also discovered that using lower efficiency, lower cost filter alternatives can be effective for reducing PMc and airborne endotoxin in homes burning biomass fuel.
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Affiliation(s)
- Marcy L McNamara
- Center for Environmental Health Sciences, Department of Biomedical Sciences, University of Montana, Missoula, MT 59801, USA.
| | | | - Erin O Semmens
- Center for Environmental Health Sciences, Department of Biomedical Sciences, University of Montana, Missoula, MT 59801, USA.
| | - Tony J Ward
- School of Public and Community Health Sciences, University of Montana, Missoula, MT 59801, USA.
| | - Curtis W Noonan
- Center for Environmental Health Sciences, Department of Biomedical Sciences, University of Montana, Missoula, MT 59801, USA.
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8
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Generation and Characterization of Indoor Fungal Aerosols for Inhalation Studies. Appl Environ Microbiol 2016; 82:2479-93. [PMID: 26921421 PMCID: PMC4959492 DOI: 10.1128/aem.04063-15] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 02/01/2016] [Indexed: 12/11/2022] Open
Abstract
In the indoor environment, people are exposed to several fungal species. Evident dampness is associated with increased respiratory symptoms. To examine the immune responses associated with fungal exposure, mice are often exposed to a single species grown on an agar medium. The aim of this study was to develop an inhalation exposure system to be able to examine responses in mice exposed to mixed fungal species aerosolized from fungus-infested building materials. Indoor airborne fungi were sampled and cultivated on gypsum boards. Aerosols were characterized and compared with aerosols in homes. Aerosols containing 107 CFU of fungi/m3 air were generated repeatedly from fungus-infested gypsum boards in a mouse exposure chamber. Aerosols contained Aspergillus nidulans, Aspergillus niger, Aspergillus ustus, Aspergillus versicolor, Chaetomium globosum, Cladosporiumherbarum, Penicillium brevicompactum, Penicillium camemberti, Penicillium chrysogenum, Penicillium commune, Penicillium glabrum, Penicillium olsonii, Penicillium rugulosum, Stachybotrys chartarum, and Wallemia sebi. They were all among the most abundant airborne species identified in 28 homes. Nine species from gypsum boards and 11 species in the homes are associated with water damage. Most fungi were present as single spores, but chains and clusters of different species and fragments were also present. The variation in exposure level during the 60 min of aerosol generation was similar to the variation measured in homes. Through aerosolization of fungi from the indoor environment, cultured on gypsum boards, it was possible to generate realistic aerosols in terms of species composition, concentration, and particle sizes. The inhalation-exposure system can be used to study responses to indoor fungi associated with water damage and the importance of fungal species composition.
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9
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Holst G, Høst A, Doekes G, Meyer HW, Madsen AM, Sigsgaard T. Determinants of house dust, endotoxin, and β-(1→3)-D-glucan in homes of Danish children. INDOOR AIR 2015; 25:245-59. [PMID: 25039673 DOI: 10.1111/ina.12143] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 07/06/2014] [Indexed: 05/24/2023]
Abstract
Little is known about the geographic variation and determinants of bacterial endotoxin and β-(1,3)-D-glucan in Danish house dust. In a population of 317 children, we: (i) described loads and concentrations of floor dust, endotoxin, and β-(1→3)-D-glucan and (ii) their correlations and (iii) assessed their determinants; (iv) Finally, we compared our findings with previous European studies. Bedroom floor dust was analyzed for endotoxin content by the kinetic limulus amoebocyte lysate assay and for β-(1→3)-D-glucan by the inhibition enzyme immunoassay. The parents answered questions regarding potential determinants. We found: geometric means (geometric standard deviations) 186 mg/m(2) (4.3) for dust; 5.46 × 10(3) EU/m(2) (8.0) and 31.1 × 10(3) EU/g (2.6) for endotoxin; and 142 μg/m(2) (14.3) and 0.71 × 10(3) μg/g (7.3) for β-(1→3)-D-glucan. High correlations (r > 0.75) were found between floor dust and endotoxin and β-(1→3)-D-glucan loads, while endotoxin and β-(1→3)-D-glucan concentrations were moderately correlated (r = 0.36-0.41) with the dust load. Having a carpet was positively associated with dust load and with endotoxin and β-(1→3)-D-glucan concentrations. Pet keeping, dwelling type, and dwelling location were determinants of endotoxin concentrations. No other determinants were associated with β-(1→3)-D-glucan concentrations. Compared with other European studies, we found lower β-(1→3)-D-glucan loads and concentrations but higher endotoxin loads and concentrations suggesting a geographically determined different composition of Danish floor dust compared with other European regions.
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Affiliation(s)
- G Holst
- Section of Environment, Occupation and Health, Aarhus University, Aarhus, Denmark
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Nevalainen A, Täubel M, Hyvärinen A. Indoor fungi: companions and contaminants. INDOOR AIR 2015; 25:125-56. [PMID: 25601374 DOI: 10.1111/ina.12182] [Citation(s) in RCA: 117] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 12/20/2014] [Indexed: 05/21/2023]
Abstract
This review discusses the role of fungi and fungal products in indoor environments, especially as agents of human exposure. Fungi are present everywhere, and knowledge for indoor environments is extensive on their occurrence and ecology, concentrations, and determinants. Problems of dampness and mold have dominated the discussion on indoor fungi. However, the role of fungi in human health is still not well understood. In this review, we take a look back to integrate what cultivation-based research has taught us alongside more recent work with cultivation-independent techniques. We attempt to summarize what is known today and to point out where more data is needed for risk assessment associated with indoor fungal exposures. New data have demonstrated qualitative and quantitative richness of fungal material inside and outside buildings. Research on mycotoxins shows that just as microbes are everywhere in our indoor environments, so too are their metabolic products. Assessment of fungal exposures is notoriously challenging due to the numerous factors that contribute to the variation of fungal concentrations in indoor environments. We also may have to acknowledge and incorporate into our understanding the complexity of interactions between multiple biological agents in assessing their effects on human health and well-being.
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Affiliation(s)
- A Nevalainen
- Institute for Health and Welfare, Kuopio, Finland
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11
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Afanou KA, Straumfors A, Skogstad A, Skaar I, Hjeljord L, Skare Ø, Green BJ, Tronsmo A, Eduard W. Profile and Morphology of Fungal Aerosols Characterized by Field Emission Scanning Electron Microscopy (FESEM). AEROSOL SCIENCE AND TECHNOLOGY : THE JOURNAL OF THE AMERICAN ASSOCIATION FOR AEROSOL RESEARCH 2015; 49:423-435. [PMID: 26855468 PMCID: PMC4741100 DOI: 10.1080/02786826.2015.1040486] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Fungal aerosols consist of spores and fragments with diverse array of morphologies; however, the size, shape, and origin of the constituents require further characterization. In this study, we characterize the profile of aerosols generated from Aspergillus fumigatus, A. versicolor, and Penicillium chrysogenum grown for 8 weeks on gypsum boards. Fungal particles were aerosolized at 12 and 20 L min-1 using the Fungal Spore Source Strength Tester (FSSST) and the Stami particle generator (SPG). Collected particles were analyzed with field emission scanning electron microscopy (FESEM). We observed spore particle fraction consisting of single spores and spore aggregates in four size categories, and a fragment fraction that contained submicronic fragments and three size categories of larger fragments. Single spores dominated the aerosols from A. fumigatus (median: 53%), while the submicronic fragment fraction was the highest in the aerosols collected from A. versicolor (median: 34%) and P. chrysogenum (median: 31%). Morphological characteristics showed near spherical particles that were only single spores, oblong particles that comprise some spore aggregates and fragments (<3.5 μm), and fiber-like particles that regroup chained spore aggregates and fragments (>3.5 μm). Further, the near spherical particles dominated the aerosols from A. fumigatus (median: 53%), while oblong particles were dominant in the aerosols from A. versicolor (68%) and P. chrysogenum (55%). Fiber-like particles represented 21% and 24% of the aerosols from A. versicolor and P. chrysogenum, respectively. This study shows that fungal particles of various size, shape, and origin are aerosolized, and supports the need to include a broader range of particle types in fungal exposure assessment.
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Affiliation(s)
- Komlavi Anani Afanou
- National Institute of Occupational Health, Department of Chemical and Biological Work Environment, Oslo, Norway
| | - Anne Straumfors
- National Institute of Occupational Health, Department of Chemical and Biological Work Environment, Oslo, Norway
| | - Asbjørn Skogstad
- National Institute of Occupational Health, Department of Chemical and Biological Work Environment, Oslo, Norway
| | - Ida Skaar
- Norwegian Veterinary Institute, Section of Mycology, Oslo, Norway
| | - Linda Hjeljord
- Norwegian University of Life Science, Institute of Chemistry, Biotechnology and Food Science, Ås, Norway
| | - Øivind Skare
- National Institute of Occupational Health, Department of Chemical and Biological Work Environment, Oslo, Norway
| | - Brett James Green
- National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Allergy and Clinical Immunology Branch, Health Effect Laboratory Division, Morgantown, West Virginia, USA
| | - Arne Tronsmo
- Norwegian University of Life Science, Institute of Chemistry, Biotechnology and Food Science, Ås, Norway
| | - Wijnand Eduard
- National Institute of Occupational Health, Department of Chemical and Biological Work Environment, Oslo, Norway
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12
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Submicronic fungal bioaerosols: high-resolution microscopic characterization and quantification. Appl Environ Microbiol 2014; 80:7122-30. [PMID: 25217010 DOI: 10.1128/aem.01740-14] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Submicronic particles released from fungal cultures have been suggested to be additional sources of personal exposure in mold-contaminated buildings. In vitro generation of these particles has been studied with particle counters, eventually supplemented by autofluorescence, that recognize fragments by size and discriminate biotic from abiotic particles. However, the fungal origin of submicronic particles remains unclear. In this study, submicronic fungal particles derived from Aspergillus fumigatus, A. versicolor, and Penicillium chrysogenum cultures grown on agar and gypsum board were aerosolized and enumerated using field emission scanning electron microscopy (FESEM). A novel bioaerosol generator and a fungal spores source strength tester were compared at 12 and 20 liters min(-1) airflow. The overall median numbers of aerosolized submicronic particles were 2 × 10(5) cm(-2), 2.6 × 10(3) cm(-2), and 0.9 × 10(3) cm(-2) for A. fumigatus, A. versicolor, and P. chrysogenum, respectively. A. fumigatus released significantly (P < 0.001) more particles than A. versicolor and P. chrysogenum. The ratios of submicronic fragments to larger particles, regardless of media type, were 1:3, 5:1, and 1:2 for A. fumigatus, A. versicolor, and P. chrysogenum, respectively. Spore fragments identified by the presence of rodlets amounted to 13%, 2%, and 0% of the submicronic particles released from A. fumigatus, A. versicolor, and P. chrysogenum, respectively. Submicronic particles with and without rodlets were also aerosolized from cultures grown on cellophane-covered media, indirectly confirming their fungal origin. Both hyphae and conidia could fragment into submicronic particles and aerosolize in vitro. These findings further highlight the potential contribution of fungal fragments to personal fungal exposure.
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13
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Adhikari A, Kettleson EM, Vesper S, Kumar S, Popham DL, Schaffer C, Indugula R, Chatterjee K, Allam KK, Grinshpun SA, Reponen T. Dustborne and airborne Gram-positive and Gram-negative bacteria in high versus low ERMI homes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 482-483:92-9. [PMID: 24642096 PMCID: PMC4046584 DOI: 10.1016/j.scitotenv.2014.02.110] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Revised: 01/27/2014] [Accepted: 02/24/2014] [Indexed: 04/13/2023]
Abstract
The study aimed at investigating Gram-positive and Gram-negative bacteria in moldy and non-moldy homes, as defined by the home's Environmental Relative Moldiness Index (ERMI) value. The ERMI values were determined from floor dust samples in 2010 and 2011 and homes were classified into low (<5) and high (>5) ERMI groups based on the average ERMI values as well as 2011 ERMI values. Dust and air samples were collected from the homes in 2011 and all samples were analyzed for Gram-positive and Gram-negative bacteria using QPCR assays, endotoxin by the LAL assay, and N-acetyl-muramic acid using HPLC. In addition, air samples were analyzed for culturable bacteria. When average ERMI values were considered, the concentration and load of Gram-positive bacteria determined with QPCR in house dust, but not air, were significantly greater in high ERMI homes than in low ERMI homes. Furthermore, the concentration of endotoxin, but not muramic acid, in the dust was significantly greater in high ERMI than in low ERMI homes. In contrast, when ERMI values of 2011 were considered, Gram-negative bacteria determined with QPCR in air, endotoxin in air, and muramic acid in dust were significantly greater in high ERMI homes. The results suggest that both short-term and long-term mold contamination in homes could be linked with the bacterial concentrations in house dust, however, only the current mold status was associated with bacterial concentrations in air. Although correlations were found between endotoxin and Gram-negative bacteria as well as between muramic acid and Gram-positive bacteria in the entire data set, diverging associations were observed between the different measures of bacteria and the home moldiness. It is likely that concentrations of cells obtained by QPCR and concentrations of cell wall components are not equivalent and represent too broad categories to understand the bacterial composition and sources of the home microbiota.
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Affiliation(s)
- Atin Adhikari
- Department of Environmental Health, University of Cincinnati, Cincinnati, OH 45267-0056, United States.
| | - Eric M Kettleson
- Department of Environmental Health, University of Cincinnati, Cincinnati, OH 45267-0056, United States
| | - Stephen Vesper
- National Exposure Research Laboratory, U.S. Environmental Protection Agency, Cincinnati, OH 45268, United States
| | - Sudhir Kumar
- Department of Environmental Health, University of Cincinnati, Cincinnati, OH 45267-0056, United States
| | - David L Popham
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, United States
| | - Christopher Schaffer
- Department of Environmental Health, University of Cincinnati, Cincinnati, OH 45267-0056, United States
| | - Reshmi Indugula
- Department of Environmental Health, University of Cincinnati, Cincinnati, OH 45267-0056, United States
| | - Kanistha Chatterjee
- Department of Environmental Health, University of Cincinnati, Cincinnati, OH 45267-0056, United States
| | - Karteek K Allam
- Department of Environmental Health, University of Cincinnati, Cincinnati, OH 45267-0056, United States
| | - Sergey A Grinshpun
- Department of Environmental Health, University of Cincinnati, Cincinnati, OH 45267-0056, United States
| | - Tiina Reponen
- Department of Environmental Health, University of Cincinnati, Cincinnati, OH 45267-0056, United States
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Leppänen HK, Nevalainen A, Vepsäläinen A, Roponen M, Täubel M, Laine O, Rantakokko P, von Mutius E, Pekkanen J, Hyvärinen A. Determinants, reproducibility, and seasonal variation of ergosterol levels in house dust. INDOOR AIR 2014; 24:248-259. [PMID: 24883434 DOI: 10.1111/ina.12078] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
UNLABELLED This study aimed to clarify the determinants that affect the concentrations of ergosterol and viable fungi in house dust and to examine the seasonal variation and reproducibility of ergosterol concentrations indoors. In studying the determinants, dust samples from living room floors and vacuum cleaner dust bags were collected from 107 farming and 105 non-farming homes. Ergosterol levels were determined with gas chromatography-mass spectrometry,and the dust bag dust was cultivated for enumeration of fungal genera. Lifestyle and environmental factors, for example using of the fireplace, and visible mold observations in homes, explained 20–26% of the variation of fungal concentrations. For the reproducibility study, samples were collected from five urban homes in four different seasons. The reproducibility of ergosterol determinations within a sample was excellent (ICC = 89.8) for floor dust and moderate (ICC = 63.8) for dust bag dust, but poor when sampling the same home throughout a year (ICC = 31.3 and 12.6, respectively) due to large temporal variation in ergosterol concentrations. In conclusion, environmental characteristics only partially predicted the variation of fungal concentrations. Based on these studies, we recommend repeated sampling of dust over time if one seeks to adequately describe overall fungal levels and exposure in a home. PRACTICAL IMPLICATIONS This study shows that levels of ergosterol and viable fungi in house dust are related to visible mold observations. Only 20% of the variation in fungal levels can be explained with questionnaires, and therefore, environmental samples need to be taken in addition. Reproducibility of ergosterol determination was excellent for floor dust, and thus, ergosterol measurements from floor dust samples could be suitable for assessing the fungal load in building investigations. The temporal variation needs to be taken into account when describing the ergosterol concentration of urban homes.
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15
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Frankel M, Hansen EW, Madsen AM. Effect of relative humidity on the aerosolization and total inflammatory potential of fungal particles from dust-inoculated gypsum boards. INDOOR AIR 2014; 24:16-28. [PMID: 23750665 DOI: 10.1111/ina.12055] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Accepted: 06/04/2013] [Indexed: 06/02/2023]
Abstract
The aim of this study was to investigate the effect of relative humidity (RH) on the aerosolization and total inflammatory potential (TIP) of microbial particles released from gypsum boards inoculated with dust samples from homes. After microbial colonization, the gypsum boards were incubated at either high or low RH. The aerosolized particles (0.54-19.8 μm), culturable fungi, β-glucan and the TIP of the aerosolized particles were quantified. Despite the colonization of several fungal groups, Penicillium dominated the aerosolized fraction. Higher emission rates of particles and culturable fungi were found from low RH compared with high RH in both the inhalable and particulate matter <1 μm (PM1 ) fractions, and the TIP was accordingly higher. However, for the aerosolized fractions, the TIP or concentration β-glucan relative to the number of fungi or particles present was higher from high RH compared with low RH. Despite the low number of culturable fungi in PM1 , this fraction showed a high TIP, and the concentration of β-glucan correlated strongly with the TIP of this fraction. The individual particles of the aerosolized PM1 fraction were more inflammatory than the larger particles of the inhalable fraction, and β-glucan may be an important contributor to the inflammatory potential of the aerosolized particles.
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Affiliation(s)
- M Frankel
- The National Research Centre for the Working Environment, Copenhagen, Denmark; Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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16
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Madsen AM, Tendal K, Frederiksen MW. Attempts to reduce exposure to fungi, β-glucan, bacteria, endotoxin and dust in vegetable greenhouses and a packaging unit. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 468-469:1112-21. [PMID: 24112965 DOI: 10.1016/j.scitotenv.2013.09.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 09/04/2013] [Accepted: 09/04/2013] [Indexed: 05/04/2023]
Abstract
Indoor handling of large amounts of plant materials occurs in different occupational settings including greenhouses and causes exposure to bioaerosols. The bioaerosol components fungi, β-glucan, bacteria and endotoxin are involved in different airway symptoms and health effects can be dose-dependent. Therefore, there is a persistent need to reduce exposure. The aims of this study were to identify tasks causing exposure and to evaluate preventive measures aimed at reducing exposure of greenhouse workers to bioaerosols, and to study factors affecting the exposure. We have focused on different exposure scenarios; one with high short-term exposure found during clearing of old cucumber plants; the other with long-term, mid-level exposure found during tomato picking, leaf nipping, stringing up tomato plants, and packaging of cucumbers. Clearing of non-dried cucumber plants compared with clearing of dried cucumber plants significantly reduced the exposure to dust, endotoxin, bacteria, fungal spores and β-glucan. More endotoxin and fungi are emitted and more of the emitted particles were of respirable size if the leaves were dried. Along the cucumber packaging line, exposure levels were highly specific to each personal subtask. The subtask 'unloading of cucumbers' was the source of exposure making task ventilation or shielding of the process a possibility. Elimination of leaf debris on the floor reduced the exposure to fungi significantly. However, leaf debris on the floor did not contribute significantly to the exposure to dust, endotoxin and bacteria. Furthermore, to eliminate leaf debris, it had to be cleared away and this was associated with a higher exposure to dust and endotoxin. The age of the plants affected the exposure level to bioaerosols with higher exposures from old plants. In conclusion, different tasks and subtasks cause very different exposure levels. It is possible to reduce exposure by identifying subtasks causing the exposure and by modifying work processes, e.g., not drying out of plants.
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Affiliation(s)
- Anne Mette Madsen
- The National Research Centre for the Working Environment, Lersø Parkallé 105, DK-2100 Copenhagen Ø, Denmark.
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McNamara M, Thornburg J, Semmens E, Ward T, Noonan C. Coarse particulate matter and airborne endotoxin within wood stove homes. INDOOR AIR 2013; 23:498-505. [PMID: 23551341 PMCID: PMC4556095 DOI: 10.1111/ina.12043] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Accepted: 03/09/2013] [Indexed: 05/08/2023]
Abstract
Emissions from indoor biomass burning are a major public health concern in developing areas of the world. Less is known about indoor air quality, particularly airborne endotoxin, in homes burning biomass fuel in residential wood stoves in higher income countries. A filter-based sampler was used to evaluate wintertime indoor coarse particulate matter (PM₁₀₋₂.₅) and airborne endotoxin (EU/m³, EU/mg) concentrations in 50 homes using wood stoves as their primary source of heat in western Montana. We investigated number of residents, number of pets, dampness (humidity), and frequency of wood stove usage as potential predictors of indoor airborne endotoxin concentrations. Two 48-h sampling events per home revealed a mean winter PM₁₀₋₂.₅ concentration (± s.d.) of 12.9 (± 8.6) μg/m³, while PM₂.₅ concentrations averaged 32.3 (± 32.6) μg/m³. Endotoxin concentrations measured from PM₁₀₋₂.₅ filter samples were 9.2 (± 12.4) EU/m³ and 1010 (± 1524) EU/mg. PM₁₀₋₂.₅ and PM₂.₅ were significantly correlated in wood stove homes (r = 0.36, P < 0.05). The presence of pets in the homes was associated with PM₁₀₋₂.₅ but not with endotoxin concentrations. Importantly, none of the other measured home characteristics was a strong predictor of airborne endotoxin, including frequency of residential wood stove usage.
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Affiliation(s)
- M. McNamara
- Department of Biomedical and Pharmaceutical Sciences, Center for Environmental Health Sciences, University of Montana, Missoula, MT, USA
| | - J. Thornburg
- RTI International, Research Triangle Park, NC, USA
| | - E. Semmens
- Department of Biomedical and Pharmaceutical Sciences, Center for Environmental Health Sciences, University of Montana, Missoula, MT, USA
| | - T. Ward
- Department of Biomedical and Pharmaceutical Sciences, Center for Environmental Health Sciences, University of Montana, Missoula, MT, USA
| | - C. Noonan
- Department of Biomedical and Pharmaceutical Sciences, Center for Environmental Health Sciences, University of Montana, Missoula, MT, USA
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Madsen AM, Tendal K, Thilsing T, Frederiksen MW, Baelum J, Hansen JV. Fungi, β-glucan, and bacteria in nasal lavage of greenhouse workers and their relation to occupational exposure. ACTA ACUST UNITED AC 2013; 57:1030-40. [PMID: 23749501 PMCID: PMC3796760 DOI: 10.1093/annhyg/met019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The nose and mouth are the first regions of the respiratory tract in contact with airborne microorganisms. Occupational exposures to airborne microorganisms are associated with inflammation and different symptoms of the airways. The purpose of this study is to investigate the relation between occupational exposure to fungi, β-glucan, and bacteria and contents of fungi, β-glucan, and bacteria in nasal lavage (NAL) of greenhouse workers. We also studied whether contents of microorganisms in NAL were related to gender, time of the work week, and runny nose. NAL samples (n = 135) were taken Monday morning and Thursday at noon and personal exposure to inhalable bioaerosols was measured during a working day. The content of fungi and β-glucan in NAL of men was affected by their exposure to fungi and β-glucan. The content of fungi, β-glucan, and bacteria in NAL was higher Thursday at noon than Monday morning. The ratios of fungi in NAL between Thursday at noon and Monday morning were 14 (median value) for men and 3.5 for women. Gender had no effect on the exposure level but had a significant effect on the content of fungi, β-glucan, and bacteria in NAL, with the highest contents in NAL of men. On Thursdays, the median content of fungi in NAL samples of men without runny noses was 9408 cfu per NAL sample, whereas the same content for women was 595 cfu per NAL sample. Workers with runny noses had fewer fungi in NAL than workers without runny noses. A higher content of β-glucan per fungal spore was found in NAL than in the air. This indicates that mainly the larger fungal spores or pollen grains deposit in the nose. The difference between genders and the fact that the content of fungi in NAL was significantly affected by the exposure indicate that the two genders are affected by the same exposure level differently.
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Affiliation(s)
- Anne Mette Madsen
- The National Research Centre for the Working Environment, Copenhagen Ø, Denmark
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Ownby DR, Peterson EL, Wegienka G, Woodcroft KJ, Nicholas C, Zoratti E, Johnson CC. Are cats and dogs the major source of endotoxin in homes? INDOOR AIR 2013; 23:219-226. [PMID: 23167871 PMCID: PMC4005287 DOI: 10.1111/ina.12016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Accepted: 11/13/2012] [Indexed: 05/31/2023]
Abstract
UNLABELLED Previous studies have suggested that exposure to cats and dogs during early childhood reduces the risk of allergic disease, possibly by increasing home endotoxin exposure. This study asked the question of whether cats and dogs are the dominant influence on dust endotoxin concentrations in homes after considering other variables reportedly associated with endotoxin. The presence of cats or dogs in homes, household and home characteristics, and dust endotoxin concentrations from 5 locations were assessed in 966 urban and suburban homes. Whether considered together as pets or as cats and dogs separately, the presence of cats and dogs significantly contributed to living room and bedroom floor endotoxin concentrations, but not to bed endotoxin concentrations. However, the two variables consistently related to endotoxin in all home sites were the home occupant density (occupants/room) and cleanliness of the home. Our data suggest that reducing occupant density and improving home cleanliness would reduce home endotoxin concentrations more than removing pet cats or dogs from the home. PRACTICAL IMPLICATIONS Many studies have shown that early childhood exposure to indoor cats or dogs is associated with a reduced risk of later allergic disease and asthma. An important question is whether alteration in allergic risk associated with cat and dog exposure results from increased endotoxin exposure or from some other associated exposure. Our findings show that cats and dogs are not the dominant source of endotoxin in homes; rather, the density of human occupation and poor cleaning contribute more consistently to higher home endotoxin concentrations especially in the beds.
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Affiliation(s)
- D R Ownby
- Division of Allergy, Immunology, Rheumatology, Department of Pediatrics, Georgia Health Sciences University, Augusta, GA 30912-3790, USA.
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