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

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

[1]  B. Leaderer,et al.  Comparisons of seasonal fungal prevalence in indoor and outdoor air and in house dusts of dwellings in one Northeast American county1 , 1999, Journal of Exposure Analysis and Environmental Epidemiology.

[2]  Chihshan Li,et al.  Microbiological indoor air quality in subtropical areas , 1993 .

[3]  Lidia Morawska,et al.  A pilot investigation into associations between indoor airborne fungal and non-biological particle concentrations in residential houses in Brisbane, Australia. , 2003, The Science of the total environment.

[4]  C Washington Winn,et al.  Koneman's Color Atlas and Textbook of Diagnostic Microbiology , 1994 .

[5]  Tiina Reponen,et al.  The indoor air quality in finnish homes with mold problems , 1991 .

[6]  H. Aydoğdu,et al.  Monitoring of Fungi and Bacteria in the Indoor Air of Primary Schools in Edirne City, Turkey , 2005 .

[7]  L. D. Robertson,et al.  Monitoring Viable Fungal and Bacterial Bioaerosol Concentrations to Identify Acceptable Levels for Common Indoor Environments , 1997 .

[8]  L. T. Wong,et al.  Thermal Environmental Interference with Airborne Bacteria and Fungi Levels in Air-Conditioned Offices , 2008 .

[9]  Pentti Kalliokoski,et al.  Occurrence and moisture requirements of microbial growth in building materials , 1992 .

[10]  Karin Foarde,et al.  Cleaning for Improved Indoor Air Quality: an Initial Assessment of Effectiveness , 1997 .

[11]  Jacek Dutkiewicz,et al.  Bacterial and fungal aerosols in indoor environment in Central and Eastern European countries. , 2002, Annals of agricultural and environmental medicine : AAEM.

[12]  J M Macher,et al.  Concentrations of airborne culturable bacteria in 100 large US office buildings from the BASE study. , 2005, Indoor air.

[13]  Hyeun Jun Moon,et al.  Investigation of Physical Characteristics of Houses and Occupants’ Behavioural Factors for Mould Infestation in Residential Buildings , 2010 .

[14]  M. S. Zuraimi,et al.  Indoor air quality and its determinants in tropical child care centers , 2008 .

[15]  Didier Raoult,et al.  16S Ribosomal DNA Sequence Analysis of a Large Collection of Environmental and Clinical Unidentifiable Bacterial Isolates , 2000, Journal of Clinical Microbiology.

[16]  T. Haahtela,et al.  Health Effects of Residents Exposed to Stachybotrys in Water-damaged Houses in Finland , 2010 .

[17]  Chi Nyon Kim,et al.  Airborne microbiological characteristics in public buildings of Korea , 2007 .

[18]  W. Dott,et al.  Relevance of airborne fungi and their secondary metabolites for environmental, occupational and indoor hygiene , 2002, Archives of Microbiology.

[19]  R. Krska,et al.  A Study of the Toxicity of Moulds Isolated from Dwellings , 2010 .

[20]  Jozef S. Pastuszka,et al.  Bacterial and fungal aerosol in indoor environment in Upper Silesia, Poland , 2000 .

[21]  J. Douwes,et al.  Bioaerosol health effects and exposure assessment: progress and prospects. , 2003, The Annals of occupational hygiene.

[22]  B. Jeršek,et al.  Assessment of Bioaerosol Concentrations in Different Indoor Environments , 2008 .

[23]  Kenneth J. Ryan,et al.  Reviews and Notes: Infectious Diseases: Sherris Medical Microbiology: An Introduction to Infectious Diseases , 1995, Annals of Internal Medicine.

[24]  K. Leszczynska,et al.  Indoor air studies of fungi contamination of social welfare home in Czerewki in north-east part of Poland. , 2005, Roczniki Akademii Medycznej w Bialymstoku.

[25]  Jagjit Singh,et al.  Building Pathology, Investigation of Sick Buildings —Toxic Moulds , 2010 .

[26]  E. Koneman.  Color atlas and textbook of diagnostic microbiology , 1983 .

[27]  John C. S. Chang,et al.  Review of quantitative standards and guidelines for fungi in indoor air. , 1996, Journal of the Air & Waste Management Association.

[28]  Ki-Youn Kim,et al.  Assessment of Bioaerosols in the Public Buildings of Korea , 2007 .

[29]  Donald C. Lehman,et al.  Textbook of Diagnostic Microbiology , 1997 .

[30]  W. Jo,et al.  Indoor and outdoor bioaerosol levels at recreation facilities, elementary schools, and homes. , 2005, Chemosphere.

[31]  D O Hryhorczuk,et al.  Association of asthma symptoms and severity with indoor bioaerosols , 2000, Allergy.

[32]  American Conference Of Governmental Industrial Hygienists 1998 Ventilation A O , 2019 .

[33]  T. Meklin,et al.  Effects of moisture-damage repairs on microbial exposure and symptoms in schoolchildren. , 2005, Indoor air.

[34]  Patricia Cruz,et al.  Detection and enumeration of airborne biocontaminants. , 2004, Current opinion in biotechnology.

[35]  16S RRNA GENE SEQUENCING FOR BACTERIAL PATHOGEN IDENTIFICATION IN THE CLINICAL LABORATORY , 2001 .

[36]  Nicolas Kalogerakis,et al.  Indoor air quality—bioaerosol measurements in domestic and office premises , 2005 .

[37]  W. Y. Chan,et al.  An Assessment of Airborne Fungi Exposure Risk Level in Air-conditioned Offices , 2009 .