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Fungi have been implicated as quantitatively the most important bioaerosol component of indoor air associated with contaminated air-conditioning systems. rarely, indoor fungi may cause human infections, but more commonly allergenic responses ranging from pneumonitis to asthma-like symptoms. From all air conditioner filters analyzed, 16 fungal taxa were isolated and identified. Aspergillus fumigatus causes more lethal infections worldwide than any other mold. Air-conditioning filters that adsorb moisture and volatile organics appear to provide suitable substrates for fungal colonization. It is important to stress that fungal colonization of air-conditioning systems should not be ignored, especially in hospital environments.
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INTRODUCTION
Fungi inhabit nearly all terrestrial environments. In
this regard, the interiors of human dwellings and
workspaces are no exception. The mycobiota of
human-inhabited indoor environments consists of
a distinctive group of organisms that collectively are
not normally encountered elsewhere. Dust forma-
tion occurs as a result of the ongoing elutriation of
airborne organic and inorganic particulate matter
that originates from a multiplicity of indoor and
outdoor sources (S co tt , 2001). House dust is a
fibrous material composed primarily of a matrix
of textile fibers, hairs, and shed epithelial debris
(Scott, 2001). Fungi commonly isolated from indoor
air include Alternaria, Aspergillus, Aureobasidium,
Cladosporium, and Penicillium species. Many of
these species may contaminate indoor air through
heating, ventilating, and air-conditioning systems
(S im on s et al., 1997). It is well known that venti-
lation systems, even those without water-containing
components, may act as a potential microbial source
in indoor air (Pa sa ne n et al., 1997). Filters are
porous soft insulation material very often used in
air-conditioning systems. Direct microscopic exam-
ination of air filters reveals pollen particles, cellulose
fibers, synthetic fibers, plant hairs, decayed leaves,
insect parts, dust mites, and many organic com-
pounds (Mo r a y and Wi l l i am s, 1990). Cellulose
and synthetic fibers probably come from indoor
sources, while the other components most likely
originate from outdoor sources. Insulation materi-
als also absorb moisture and volatile organics and
provide suitable substrates for fungal colonization
(S im on s et al., 1997). These organics represent
excellent nutrients for fungal growth, with the result
that air filters harbor an abundance of fungal hyphae
and spores (Yo u n g, 1996). Dust and microorgan-
isms may accumulate in supply air ducts during
installation or later from the outdoor air due to
leakages between the filter cassette and the assembly
frame, or from insufficient efficiency of the filter
(P a s an en et al., 1997).
Human infections caused by indoor fungi are
very seldom because of the highly efficient defense
mechanisms of human cells, such as the cell-medi-
ated response (P er de l i et al., 2006). However,
conidia and fragments of hyphae may sometimes
cause allergenic responses, and some metabolites
produced by fungi may be toxic or have immu-
nomodulating activity in humans (S i mo ns et
al., 1997). Also, reduction in the host organisms
defensive ability, whether due to cancer, AIDS,
FUNGAL COLONIZATION OF AIR-CONDITIONING SYSTEMS
MILICA LJALJEVIĆGRBIĆ, JELENA VUKOJEVIĆ, and M. STUPAR
Institute of Botany and Jevremovac Botanical Garden, Faculty of Biology, University of Belgrade, 11000 Belgrade, Serbia
Abstract — Fungi have been implicated as quantitatively the most important bioaerosol component of indoor air associ-
ated with contaminated air-conditioning systems. Rarely, indoor fungi may cause human infections, but more commonly
allergenic responses ranging from pneumonitis to asthma-like symptoms. From all air conditioner filters analyzed, 16
fungal taxa were isolated and identified. Aspergillus fumigatus causes more lethal infections worldwide than any other
mold. Air-conditioning filters that adsorb moisture and volatile organics appear to provide suitable substrates for fungal
colonization. It is important to stress that fungal colonization of air-conditioning systems should not be ignored, espe-
cially in hospital environments.
Key words: Indoor air, air-conditioning filters, micromycetes, human health
UDC 614.71:628.8:582.28
201
Arch. Biol. Sci., Belgrade, 60 (2), 201-206, 2008 DOI:10.2298/ABS0802201L
M. LJALJEVIĆ-GRBIĆ ET AL.
202
organ transplantation, or any other medical rea-
son, may lead to the uncontrolled multiplication of
fungi and consequent onset of infection, sometimes
with fatal effects (P er de li et al., 2006). There are
reports that four patients died and 11 contracted
the respiratory disease aspergillosis at the Alcala de
Hanares Hospital, near Madrid (Spain). The disease
was caused by inhaling the spores of Aspergillus
fumigatus, which was later detected in the hospital’s
air-conditioning system (http://www.acr-news.com/
news)
MATERIALS AND METHODS
Samples studied
Fifteen dust samples were collected from air-
conditioning filters from school classrooms and
offices. Also, five swab samples were collected from
an air conditioner in a hospital surgical ward. None
of the analyzed filters from classrooms and offices
had been removed or cleaned for two years (Fig. 1a),
whereas those from the hospital were cleaned once
a month on a regular basis.
Direct examination
The tape lift technique used for direct examina-
tion allows for immediate determination of the pres-
ence of fungal spores and identification of the types
of fungi present. Direct examinations should only be
used to sample visible mold growth in contaminated
air-conditioning filters. Samples were collected by
pulling the tape of the filter surface with slow steady
pressure, holding only the tape edges, after which
they were put on slides for light microscopy.
Determination of total spore concentrations in dust
Culturable fungal spore concentrations are pre-
sented in terms of colony-forming units (CFU)/g of
dust. Sub-samples (0.5 g) were taken from each dust
sample and suspended in distilled water (0.0425 g/l
KH2PO4, 0.25 g/l MgSO4, 0.008 g/l NaOH, 0.02%
Tween 80 detergent). Dilution series were prepared
and three succesive dilutions were plated in tripli-
cate on malt agar medium (MA) with the antibiotic
streptomycin, which was added during the prepara-
tion process in order to prevent bacterial growth
(P a s an en et al., 1997). The plates were incubated
on 22 ± 2ºC and read after 72 to 120 hours. Fungal
colonies formed on the medium were identified
on the basis of both macroscopic and microscopic
characteristics of each isolated colony using identifi-
cation keys (A i n s wo rt h et al., 1973; A r x, 1974;
E ll i s and E l l i s , 1997; P i t t , 1979; R a pe r, and
F e n ne l 1965).
RESULTS AND DISCUSSION
The direct examination method revealed the
presence of different fungal structures: conidia,
conidiophores, chlamidospores and mycelia (Fig. 1b-
f). From all dust samples analyzed from classrooms,
offices, and hospital air-conditionning systems, six
fungal genera with different numbers of species were
recorded: Cladosporium, Penicillium, Aspergillus,
Alternaria, Epiccocum, and one Ascomycotyna from
the order Sphaeriales (Table 1). The fungal colonies
isolated from different sources were characterized
not only by the presence of different species, but also
by their different abundance (Fig. 2a). The genus
Aspergillus with five species was the most frequent
(Tabel 1, Fig. 2b, e, f). The abundance of fungal
colonies was much higher in classrooms and offices
than in the hospital. Aspergillus and Penicillium
species were dominant. Alternaria alternata and
Cladosporium cladosporioides were the most frequent
dematiaceous fungi (Fig. 2c, d). Fungal growth was
quantified by the number of CFUs. Culturable spore
concentrations in 15 dust samples varied from 104 to
106 CFU/g. In central Finland, culturable and total
fungi in dust accumulated in air ducts in single-fam-
ily houses varied from 104 to 108 CFU/g (P a sa ne n
et al., 1997).
The results of this research confirmed previous
findings that air-conditioning systems are highly
linked with fungal pollution of indoor air. The diver-
sity and abundance of fungal species isolated from
different air-conditioning systems can be attrib-
uted to different ways of maintaining the systems
themselves. Greater numbers of fungal genera and
species with much higher colony abundance were
expected and found in samples isolated from the air-
conditioning systems from classrooms and offices
since these systems were not cleaned after installa-
FUNGI FROM AIR CONDITIONING SYSTEMS 203
Fig. 1. Fungal structures from air conditioner filter dust: a) two years uncleaned air conditioner
filter; b) the conidial chain of Aspergillus ochraceus; c) conidiophores with terminal conidium of
Cladosporium sphaeospermum; d) mycelia with chlamydospores inside filter fiber; e) chlamidospore;
f) conidia of Alternaria sp.
tion (Fig. 1a). Only two fungal species were found
in samples from the hospital units, with very low
colony abundance. This result is worrying because
one of the two isolated species was Aspergillus versi-
color (Fig. 2e). Aspergillus is a large genus of fungal
molds, of which only a few species cause human
infections, most commonly A. fumigatus. Spores
from these species are widespread in the environ-
ment, occurring in soil, in dust, and in outdoor and
indoor air. Known as aspergillosus, fungal infection
with Aspergillus ranges from the benign to the fatal.
Healthy individuals usually inhale Aspergillus spores
M. LJALJEVIĆ-GRBIĆ ET AL.
204
without any untoward effects, but sometimes con-
tract relatively benign infections of the lungs and
sinuses. In susceptible compromised patients, how-
ever, inhalation leads to multiplication of the fungus
in the lungs and subsequent invasive infection that
may spread to any organ of the body. Dissemination
to the brain, gastrointestinal tract, and other organs
occurs in up to 30% of cases. The disseminated infec-
tion is usually fatal, partly because early diagnosis is
difficult and treatment often ineffective (F re nc h ,
Fig. 2. Micromycetes isolated from air conditioner filter dust: a) fungal colonies on MA;
b) Aspergillus ochraceus; c) Alternaria alternata; d) Cladosporium cladosporioides; e) As-
pergillus versicolor; f) Aspergillus fumigatus.
FUNGI FROM AIR CONDITIONING SYSTEMS 205
2005). Carpet dust samples (n = 11) contained A.
versicolor in concentrations ranging from <2.5 × 101
to 3.6 × 105 (median, 3.1 × 104) CFU/g of dust, and
the median proportion of A. versicolor in total cul-
turable fungi was 18%. Based on thin-layer chroma-
tography detection of sterigmatocystin, 49 of 50 A.
versicolor isolates (98%) where found to be toxigenic
in vitro (En ge l h a r t et al., 2002). Many Aspergillus
species are well known as potential producers of
mycotoxins and other volatile harmful compounds,
and many of them can cause aspergillosis in humans.
Hospitals and other medical facilities are places were
patients with damaged immune systems are com-
monly found. These patients are very receptive to
fungal infections. In order to avoid unwanted fungal
infections in hospitals, the air-conditioning systems
must be subjected to regular maintenance in order
to reduce potential fungal pollution.
Three features of mold biochemistry are of spe-
cial interest from the standpoint of human health.
Molds contain glucan, a compound with inflamma-
tory properties. Spores and mycelial fragments con-
tain allergens (G or ny et al., 2002). The spores of
some species contain low-molecular-weight chemi-
cals that are cytotoxic or have other toxic proper-
ties. Some molds, such as A. fumigatus, can cause
opportunistic infection in immunocompromised
and healthy individuals and severe allergic diseases,
such as asthma or cystic fibrosis (Burge, 2000). In
our previous investigations, Aspergillus species were
recorded in different substrata. Fungal spores can
spread from different sources and contaminate air
conditioning filters (K at ar a n o v s k i et al., 2007;;
L j a lj e v i ć and Vu k o j e vi ć , 1997).
Acknowledgments - The present research was funded by the
Serbian Ministry of Science and Environmental Protection
through project No. 143041.
REFERENCES
Ainsworth, G. C., Sparow, F. K., and A. S. Sussman (1973). The
Fungi, Volume IVA, Taxononomic Review with Keys:
Ascomycetes and Fungi Imperfecti. Academic Press, New
York and London.
Arx, J. A., von (1974). The Genera of Fungi. Sporulating in Pure
Culture.
Burge, H. A. (2000). The Fungi. In: Indoor Air Quality Handbook
(Eds. J. D. Spengler, J. M. Samet, and J. F. McCarthy),
45.1–45.33. McGraw-Hill, New York.
Ellis, M. B., and J. P. Ellis (1997). Microfungi on Land Plants.
An Identification Handbook. The Richmond Publishing
Co. Ltd.
Engelhart, S., Loock, A., Skutlarek, D., Sagunski, H., Lommel, A.,, S., Loock, A., Skutlarek, D., Sagunski, H., Lommel, A.,Loock, A., Skutlarek, D., Sagunski, H., Lommel, A.,, A., Skutlarek, D., Sagunski, H., Lommel, A.,A., Skutlarek, D., Sagunski, H., Lommel, A.,, D., Sagunski, H., Lommel, A.,D., Sagunski, H., Lommel, A.,, H., Lommel, A.,H., Lommel, A., Lommel, A.,Lommel, A.,, A.,A.,
F�rber, H.,�rber, H.,rber, H.,, H.,H., and M. Exner (2002). Occurrence of toxigenic of toxigenicof toxigenic toxigenicoxigenic
Aspergillus versicolor versicolorversicolor isolates and sterigmatocystin insolates and sterigmatocystin in and sterigmatocystin inand sterigmatocystin in sterigmatocystin interigmatocystin in inin
carpet dust from damp indoor environments. dust from damp indoor environments.dust from damp indoor environments. from damp indoor environments.from damp indoor environments. damp indoor environments.damp indoor environments. indoor environments.indoor environments. environments.environments. Appl.
Environ. Microbiol. 68, 3886–3890.
French, G. L. (2005). Prevention of hospital-acquired aspergillo-
sis infection during demolition and building work. Hosp.
Engin. Facil. Management 2, 31-32.
Górny, R. L., T. Reponen, K. Willeke, D. Schmechel, E. Robine, M.
Boissier, and C. A. Grinshpun (2002). Fungal fragments
as indoor air contaminants. App. Environ. Microbiol. 68,
3522–3531.
Kataranovski, M., Glamočlija, J., Ljaljević Grbić, M., and D.
Kataranovski (2007). First record of the presence of
pathogenic and toxigenic fungi in Norway rat popula-
tions from urban and suburban habitats in Serbia. Arch.
Biol. Sci. (Belgrade), 59 (3), 49P-50P.
Ljaljević, M., and J. Vukojević (1997). Aspergillus species from
Savsko jezero reservoir. Arch. Biol. Sci. (Belgrade) 49(3-
4), 123-128.
Moray, P., and C. Williams (1990).Porous insulation inbuildings:. Porous insulation in buildings:
a potential source of microorganisms, In: The Proceedings
of the 5th International Conference on Indoor Air Quality
Fungal taxa
Classrooms,
offices
Hospital
Alternaria alternata
+
Aspergillus flavus
+
Aspergillus fumigatus
+
Aspergillus niger
+
Aspergillus ochraceus
+
Aspergillus versicolor
+
Botrytis cinerea
+
Cladosporium herbarum
+
Cladosporium sp.
+
Cladosporium sp.
+
Epiccocum purpurascens
+
Mycelia sterilia
+
Penicillium veruccosum var. cyclopium
+
Penicillium spp.
+
Sphaeriales
+
Table 1. Micromycetes isolated from analyzed filter dust of air-
conditioning systems.
M. LJALJEVIĆ-GRBIĆ ET AL.
206
and Climate «Indoor Air», 4, 529-533.
Pasanen, L. A., Kujanpaa, L., Pasanen, P., Kalliokoski, P., and
G. Blomquist (1997). Culturable and total fungi in dust
accumulated in air ducts in single-family houses. Indoor
Air 7, 121-127.
Perdelli, F., Christina, M. L., Sartini, M., Spagnolo, A. M.,
Dallera, M., Ottria, G., Lombardi, R., Grimaldi, M., and P.
Orlando (2006). Fungal contamination in hospital envi-
roments. Infection Control Hosp. Epidemiol. 27, 44-47.
Pitt, J. I. (1979). The Genus Penicillium and Its Teleomorphic
States Eupenicillium and Talaromyces. Academic Press.
Raper, B. K., and I. D. Fennel (1965). The Genus Aspergillus. The
Williams and Wilkins Company, Baltimore.
Scott, J. A. (2001).. Studies on Indoor Fungi. PhD Thesis,
Department of Botany, University of Toronto.
Simmons, R. B., Noble, J. A., Price, D. L., Crow, S. A., and D. G.
Ahearn (1997). Fungal colonization of automobile air-
conditioning systems. J. Indust. Microbiol. Biotechnol.
19, 150-153.
Yang, S. C., (1996). Fungal colonization of HVAC and fiber-
glass air-duct liner in the USA. In: Proceedings of the
7th International Conference of Indoor Air Quality and
Climate, 3, 173-177.
AC System Implicated in Spanish Hospital Deaths (n.d.).
ACR News (The Web Site for Air-Conditioning and
Refrigeration Professionals). Published on March, 16,
2007. Retrieved from http://www.acr-news.com/news.
КОЛОНИЗАЦИЈА КЛИМА УРЕЂАЈА МИКРOГЉИВАМА
МИЛИЦА ЉАЉЕВИЋ ГРБИЋ, ЈЕЛЕНА ВУКОЈЕВИЋ и М. СТУПАР
Институт за ботанику и Ботаничка башта «Јевремовац», Биолошки факултет, Универзитет у Београду,
11000 Београд, Србија
Микрогљиве, као квантитативно најзначајни-
је биоаеросолне компоненте ваздуха у затворе-
ним просторијама, су чести контаминанти клима
уређаја. Оне могу изазвати алергијске реакције
типа пнеумонитиса и симптоме сличне астми, а
ређе могу бити и изазивачи хуманих инфекција.
Из анализираних клима уређаја изоловано је и
идентификовано 16 таксона микрогљива. Изо-
ловани Aspergillus fumigatus је познат коо изази-
вач леталних инфекција широм света. Филтери
клима уређаја који апсорбују влагу и органске
материје су погодан супстрат за колонизацију
микрогљивама. Веома је значајно напоменути
да се колонизација клима уређаја микрогљивама
не сме игнорисати и то нарочито у болничким
установама.
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Contemporary lifestyles dictate that people spend between 60 and 90% of their daily lives indoors. For those living in warm climates, air conditioning is thus considered a necessity. Air conditioners function by removing hot and humid air from building interior and replacing it with cooler air. Microorganisms are considered among the most important sources of poor quality of indoor air, and contamination of this air by microbial pollutants is being increasingly recognized as a public health problem and a probable cause of the so-called sick building syndrome. In this regard, microfiber glass panel filters are considered to provide an effective solution for air filtration and have been demonstrated to improve air quality in many applications. However, recent research has demonstrated that certain microorganisms are able to colonize panel filter surfaces. Studies on selected microbes isolated from the most commonly used filters have revealed that the bacterial and fungal moist masses carried on sponge-type filters are greater than those carried on polyester and high-efficiency particulate air (HEPA) filters. Moreover, microbial moist mass has been found to increase with increasing incubation time. In addition, recent research has shown that certain microorganisms, particularly fungi, can colonize the materials used in heating, ventilation, and airconditioning systems (HVAC).
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Low-temperature Technologies. Edited by: Tatiana Morosuk and Muhammad Sultan. ISBN: 978-1-83880-667-5. Print ISBN 978-1-83880-666-8. eBook (PDF) ISBN: 978-1-83880-668-2. Published: June 10th 2020.
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Air samples and swab samples of the air conditioning vents were collected from 29 automobiles in the metropolitan region of Atlanta, GA, and cultured for fungi. Among the fungi observed, species of Acremonium, Aspergillus, Alternaria, Aureobasidium, Cladosporium, and Penicillium were in the highest densities. Transparent adhesive tape imprints, SEM observations, and enrichment culture of components of five systems demonstrated fungal hyphae on the metal surfaces and within the matrix of various insulation materials. The evaporator removed from one automobile because of a series of complaints of noxious odors was densely colonized by Penicillium viridicatum. The amplification of known allergenic and odor-producing fungi occurred within the automobile air conditioning systems.
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In 15 animals (33.3%), fungi were detected in inoculations from swabs of the snout; in 20 animals (44.4%), fungal growth was detected in lung homogenate inoculations; and nine ani- mals (20.0%), fungi were detected in inoculations of both snout swabs and lung homogenates. In seven cases (15.5%), the pres- ence of fungi on nasal skin and in the lungs was coincident. In three animals, two or more fungal species were present in the lungs or on the snout. Penicillium species were the most abun- dantly represented fungi detected in inoculations of both lung homogenates (in 33.3% mof individuals) and swabs from the snout (in 13.3% of individuals). The presence of Aspergillus species was noted in lungs of 8.9% and on snouts of 8.9% of ex- amined individuals, while Paecilomyces varioti was recorded in
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The aerosolization process of fungal propagules of three species (Aspergillus versicolor, Penicillium melinii, and Cladosporium cladosporioides) was studied by using a newly designed and constructed aerosolization chamber. We discovered that fungal fragments are aerosolized simultaneously with spores from contaminated agar and ceiling tile surfaces. Concentration measurements with an optical particle counter showed that the fragments are released in higher numbers (up to 320 times) than the spores. The release of fungal propagules varied depending on the fungal species, the air velocity above the contaminated surface, and the texture and vibration of the contaminated material. In contrast to spores, the release of fragments from smooth surfaces was not affected by air velocity, indicating a different release mechanism. Correlation analysis showed that the number of released fragments cannot be predicted on the basis of the number of spores. Enzyme-linked immunosorbent assays with monoclonal antibodies produced against Aspergillus and Penicillium fungal species showed that fragments and spores share common antigens, which not only confirmed the fungal origin of the fragments but also established their potential biological relevance. The considerable immunological reactivity, the high number, and the small particle size of the fungal fragments may contribute to human health effects that have been detected in buildings with mold problems but had no scientific explanation until now. This study suggests that future fungal spore investigations in buildings with mold problems should include the quantitation of fungal fragments.
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Over the past decade, there has been growing concern regarding the role of toxigenic fungi in damp indoor environments; however, there is still a lack of field investigations on exposure to mycotoxins. The goal of our pilot study was to quantify the proportion of toxigenic Aspergillus versicolor isolates in native carpet dust from damp dwellings with mold problems and to determine whether sterigmatocystin can be detected in this matrix. Carpet dust samples (n = 11) contained from <2.5 × 101 to 3.6 × 105 (median, 3.1 × 104) A. versicolor CFU/g of dust, and the median proportion of A. versicolor from total culturable fungi was 18%. Based on thin-layer chromatography detection of sterigmatocystin, 49 of 50 A. versicolor isolates (98%) were found to be toxigenic in vitro. By using high-performance liquid chromatography-electrospray ionization tandem mass spectrometry, sterigmatocystin could be detected in low concentrations (2 to 4 ng/g of dust) in 2 of 11 native carpet dust samples. From this preliminary study, we conclude that most strains of A. versicolor isolated from carpet dust are able to produce sterigmatocystin in vitro and that sterigmatocystin may occasionally occur in carpet dust from damp indoor environments. Further research and systematic field investigation are needed to confirm our results and to provide an understanding of the health implications of mycotoxins in indoor environments.
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To assess the degree of fungal contamination in hospital environments and to evaluate the ability of air conditioning systems to reduce such contamination. We monitored airborne microbial concentrations in various environments in 10 hospitals equipped with air conditioning. Sampling was performed with a portable Surface Air System impactor with replicate organism detection and counting plates containing a fungus-selective medium. The total fungal concentration was determined 72-120 hours after sampling. The genera most involved in infection were identified by macroscopic and microscopic observation. The mean concentration of airborne fungi in the set of environments examined was 19 +/- 19 colony-forming units (cfu) per cubic meter. Analysis of the fungal concentration in the different types of environments revealed different levels of contamination: the lowest mean values (12 +/- 14 cfu/m(3)) were recorded in operating theaters, and the highest (45 +/- 37 cfu/m(3)) were recorded in kitchens. Analyses revealed statistically significant differences between median values for the various environments. The fungal genus most commonly encountered was Penicillium, which, in kitchens, displayed the highest mean airborne concentration (8 +/- 2.4 cfu/m(3)). The percentage (35%) of Aspergillus documented in the wards was higher than that in any of the other environments monitored. The fungal concentrations recorded in the present study are comparable to those recorded in other studies conducted in hospital environments and are considerably lower than those seen in other indoor environments that are not air conditioned. These findings demonstrate the effectiveness of air-handling systems in reducing fungal contamination.
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Abstract Fungal spore content in dust accumulated in air ducts was investigated in 24 mechanically ventilated single-family houses of which 15 had also a central air heating system. Dust was collected from the ducts simultaneously with cleaning of the ventilation systems. Besides spore concentrations and flora of culturable fungi, total fungal spore concentrations were determined in dust samples by the aqueous two-phase technique and spore counting with epifluorescence microscopy. Culturable spore concentrations in the dust varied from 104 to 107 CFU/g and total spore concentrations from 107 to 108 spores/g. Total spore concentrations in the duct dust were significantly higher in the air heated houses than in the other mechanically ventilated houses. The difference resulted mainly from a higher proportion of recirculation air and a higher age of the air heated houses. Cladosporium, Penicillium, Aspergillus and yeasts consisted of >90% of fungal flora in the dust. Although total spore concentrations were at the same level both in the exhaust and in the supply ducts in both types of house, culturable fungal spore concentrations were slightly higher in the exhaust ducts than in the supply ducts. The proportion of culturable spores was <5% of total spores in dust accumulated in the ducts.
СТУПАР Институт за ботанику и Ботаничка башта «Јевремовац», Биолошки факултет, Универзитет у Београду
  • Колонизација Клима
  • Уређаја Микрoгљивама
  • Јелена Љаљевић Грбић
  • М Вукојевић
КОЛОНИЗАЦИЈА КЛИМА УРЕЂАЈА МИКРOГЉИВАМА МИЛИЦА ЉАЉЕВИЋ ГРБИЋ, ЈЕЛЕНА ВУКОЈЕВИЋ и М. СТУПАР Институт за ботанику и Ботаничка башта «Јевремовац», Биолошки факултет, Универзитет у Београду, 11000 Београд, Србија
Fungal colonization of HVAc and fiberglass air-duct liner in the uSA
  • S C Yang
Yang, S. C., (1996). Fungal colonization of HVAc and fiberglass air-duct liner in the uSA. In: Proceedings of the 7 th International Conference of Indoor Air Quality and Climate, 3, 173-177.