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Pollen transport by clothes

DOI: 10.1007/s10453-011-9200-8
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Juha Jantunen
Juha Jantunen
Juha Jantunen
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Abstract

Pollen transport into houses via clothing was studied on different types of fabrics after clothing was aired or worn outdoors. After walking through grassland, 68 pollen grains/cm2 were found on clothes (tape samples). The amount of grass pollen, and especially pollen from insect-pollinated plants, increased from the shirt towards the shoes. The amount of pollen on clothes aired outdoors in a yard depended on the concentration in the ambient air and the texture of the fabrics. On vacuumed samples, 1.2 grains/cm2/h adhered to the furry fabric of fleece and wool, whereas only 0.3 grains/cm2/h adhered to a tight weave polyamide coat and a denim jacket. A moist cotton shirt gave slightly higher pollen counts in both the tape (8.6 grains/cm2/h) and the vacuumed samples (1.0 grains/cm2/h) compared to a dry shirt (5.6 and 0.6 grains/cm2/h), but the difference was not significant. Tape samples gave tenfold higher pollen numbers compared to vacuumed samples, probably due to the more optimal location of the tape sampling area on top of the shoulders. We conclude that clothing constitutes an important route for carrying allergenic pollen into houses. Pollen transport can be decreased by shaking outdoor clothing before entering a residence. In our case, shaking removed 68% pollen grains from trousers.
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1 23
Aerobiologia
International Journal of Aerobiology -
including the online journal `Physical
Aerobiology'
ISSN 0393-5965
Volume 27
Number 4
Aerobiologia (2011) 27:339-343
DOI 10.1007/s10453-011-9200-8
Pollen transport by clothes
Juha Jantunen & Kimmo Saarinen
1 23
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BRIEF COMMUNICATION
Pollen transport by clothes
Juha Jantunen •Kimmo Saarinen
Received: 21 October 2010 / Accepted: 1 February 2011 / Published online: 16 February 2011
ÓSpringer Science+Business Media B.V. 2011
Abstract Pollen transport into houses via clothing
was studied on different types of fabrics after clothing
was aired or worn outdoors. After walking through
grassland, 68 pollen grains/cm
2
were found on
clothes (tape samples). The amount of grass pollen,
and especially pollen from insect-pollinated plants,
increased from the shirt towards the shoes. The
amount of pollen on clothes aired outdoors in a yard
depended on the concentration in the ambient air and
the texture of the fabrics. On vacuumed samples, 1.2
grains/cm
2
/h adhered to the furry fabric of fleece and
wool, whereas only 0.3 grains/cm
2
/h adhered to a
tight weave polyamide coat and a denim jacket. A
moist cotton shirt gave slightly higher pollen counts
in both the tape (8.6 grains/cm
2
/h) and the vacuumed
samples (1.0 grains/cm
2
/h) compared to a dry shirt
(5.6 and 0.6 grains/cm
2
/h), but the difference was not
significant. Tape samples gave tenfold higher pollen
numbers compared to vacuumed samples, probably
due to the more optimal location of the tape sampling
area on top of the shoulders. We conclude that
clothing constitutes an important route for carrying
allergenic pollen into houses. Pollen transport can be
decreased by shaking outdoor clothing before enter-
ing a residence. In our case, shaking removed 68%
pollen grains from trousers.
Keywords Betula Fabric Indoor exposure
Pinus sylvestris Pollen
1 Introduction
Indoor air quality is important to human health
because people spend most of their time indoors. For
allergic people, indoor exposure to pollen and fungal
spores is of particular concern. Large amounts of
pollen have been found inside houses and public
buildings (D’Amato et al. 1996; Enomoto et al. 2004;
Takahashi et al. 2008, Tormo-Molino et al. 2009).
Pollen can float into a house through open windows,
doors and unfiltered ventilation systems. In a recent
study, the amount of airborne pollen indoors was
dependent on the measuring distance from ventilation
openings, the outdoor concentration and the rate of
the incoming airflow indoors (Jantunen and Saarinen
2009). With increased airflow from two open win-
dows on opposite walls of a room, a high number of
pollen grains penetrated deeply into the house.
Pollen can also be carried in on the feet and bodies
of people and pets (Ishibashi et al. 2008; Vural and
Ince 2008). It is often suggested that clothes consti-
tute an important entry route. Yet pollen has been
searched for and counted on fabrics in only a few
studies (Kiyosawa and Yoshizawa 2002; Zavada
et al. 2007; Takahashi et al. 2008). We evaluated
the importance of clothes on pollen transport into
houses by studying different types of fabrics after the
J. Jantunen (&)K. Saarinen
South Karelia Allergy and Environment Institute,
La
¨a
¨ka
¨ritie 15, 55330 Tiuruniemi, Finland
e-mail: jjantune@nic.fi
123
Aerobiologia (2011) 27:339–343
DOI 10.1007/s10453-011-9200-8
Author's personal copy
clothes had been aired or worn outdoors. The main
objectives were to determine (1) how much pollen
may adhere to fabrics from the air and directly from
the inflorescences of plants, (2) what is the impor-
tance of different types of fabrics in regard to the
amount of pollen trapped on the clothes and (3) how
much pollen can be removed from clothes by shaking
the fabric.
2 Materials and methods
The pollen on clothes was studied in Lappeenranta,
SE Finland. Two types of sampling protocols were
carried out.
(1) Pollen adhering to clothes directly from plants
was studied in the middle of the hay pollen season on
2.7.2008. After walking through grassland (500 m), a
total of 23 pollen samples on clothes were collected
using tape. Samples were taken from four different
trousers at knee height at both the front and the back
of the trouser leg and also before and after shaking
and beating the fabric thoroughly by hand. At the
same time, pollen samples were taken from two
different jogging shoes, two pairs of socks and three
t-shirts. The tape was pressed against the fabric five
times before being placed on a glass slide. Pollen
counts were converted into grains/cm
2
using a
multiplication factor of 0.85 (5 9searched slide area
(2 91.9 cm 90.0622 cm))
-1
.
(2) Airborne pollen adhering to textiles was
studied in a yard for 7 days in the birch pollen
season (4.5.2009–15.5.2009) and on 2 days in the
pine pollen season (1.6.2009 and 9.6.2009). Seven
different fabric types, comprising a polyamide coat,
denim jacket, dry and moist cotton shirt, woollen
sweater, fleece sweater and terry towel, were hung
out in a yard surrounded by mixed forest dominated
by birches and pines. After airing for 3–5 h (starting
at 10–11 a.m.), the fabrics were carried inside for
pollen sampling. First, we took tape samples from the
top of the shoulders according to the previous part of
the study. The second, samples were vacuumed on to
glass microfiber filters (Whatman GF/A) on the
vertical and the top area of the shoulders
(40 cm 960 cm). A piece from the edge to the
centre was cut from the filters and placed on a glass
slide. Pollen was counted using a microscope after
the filters were made transparent with immersion oil.
Pollen counts from 2 to 3 transects from edge to
centre (2.5 cm) were converted into grains/cm
2
using
a multiplication factor of 0.065 ((filter area) 9(-
searched slide area)
-1
9(vacuumed area)
-1
).
Pollen counts on clothes were compared to birch and
pine pollen concentrations in the ambient air measured
in the same yard at a height of 5 m using rotorod-type
impaction samplers, 3–5 air samples being collected
during the measuring day. The mean values of pollen
collected at two ends of the U-shaped rods were used
for analysis. Pollen data were converted into concen-
tration values (grains/m
3
) using a multiplication
factor of 0.80 (rod width (0.0019 m) 9rod height
(0.019 m) 9head diameter (0.08 m) 9p9RPM
(2,300) 9time rod used (60 min))
-1
.
Pollen counts before and after shaking the trousers
were compared using Wilcoxon’s nonparametric
paired test. Spearman’s correlation test was used to
determine a possible relationship between the pollen
counts on the fabrics and the pollen concentration in
the ambient air. The amount of pollen adhering to the
fabrics from the air was compared using a Friedman’s
statistical test for nonparametric repeated measures
including a Conover’s post hoc test.
3 Results
Considerable amounts of pollen adhered to clothes in
direct contact with vegetation. After the walk through
the grassland, 12–230 pollen grains/cm
2
were
counted on clothes (mean 68 grains/cm
2
). The
amount of grass pollen, and especially that of
insect-pollinated plants, increased from the shirts
towards the shoes (Fig. 1). On average, the front of
the trousers acquired 64 grass pollen grains/cm
2
(SD
27) and the back 38 grains/cm
2
(SD 18). According to
these results, the total amount of grass pollen on the
trousers was close to 150,000. Pollen concentrations
decreased by 68% after shaking (from 86 to
21 grains/cm
2
;P=0.025).
Airborne tree pollen adhered to the clothes as well.
The amount of pollen on clothes aired in a yard
depended on the concentration in the ambient air and
the texture of the fabric. The mean number of pollen
grains on tape samples varied between 0.5 and
2.4 pollen grains/cm
2
/h when the concentration in
the air was less than 700 grains/m
3
. With concentra-
tions of over 1,500 grains/m
3
, the pollen counts were
340 Aerobiologia (2011) 27:339–343
123
Author's personal copy
7.6–14.6 grains/cm
2
/h. The highest total number of
pollen grains on a single day was 143 grains/cm
2
on a
moist shirt (1.6.2009). The amount of pollen on
vacuumed samples was lower but the counts from
cotton (r
S
=0.92, P\0.001), tight weave fabrics
(r
S
=0.90, P\0.001) and furry fabrics (r
S
=0.88,
P\0.01) had a strong positive correlation with the
pollen concentration in the ambient air (Fig. 2).
On the vacuumed samples, the amount of pollen
on clothes decreased towards the tighter weave
fabrics (Fig. 3). More pollen adhered to the furry,
loosely woven fabric of fleece and wool (mean
1.2 grains/cm
2
/h) compared to the polyamide coat
and the denim jacket (0.3 grains/cm
2
/h). The
highest single day counts were measured on towel
(1.6.2009; 26.7 grains/cm
2
) and on wool (13.5.2009;
16.0 grains/cm
2
).
The results from the pollen counts determined
from the tape samples were inconsistent compared to
the texture of the fabrics (Table 1). For example, the
average amount of pollen on the woollen sweater
(mean 3.8 grains/cm
2
/h) and the towel (4.0 grains/
cm
2
/h) was slightly lower than on the polyamide coat
(6.5 grains/cm
2
/h), probably due to pollen submerged
beyond reach of the tape on the uneven surface of the
fabric. The moist cotton shirt gave slightly higher
pollen counts on both the tape (8.6 grains/cm
2
/h) and
the vacuumed samples (1.0 grains/cm
2
/h) compared
to the dry shirt (5.6 and 0.6 grains/cm
2
/h), but the
difference was not significant.
4 Discussion
Large numbers of pollen grains were found on fabrics,
both after walking through grassland and after airing
the clothes. The highest pollen levels were found on
shoes, this possibly being the result of several days’
accumulation of pollen on unclean fabric. Socks also
carried some of the highest pollen loads, indicating that
more pollen adhered to fabric in direct contact with
plants. Pollen from the air became trapped in t-shirts,
and the inflorescences of the tallest hay plants in the
grassland being unable to reach the height of the shirt.
The pollen load on t-shirts after walking (tape:
12–63 grains/cm
2
) was fairly comparable with that on
t-shirts after airing for 3–5 h (tape: 3–71 grains/cm
2
).
The type of fabric and the pollen concentration in
the ambient air had a significant effect on the amount of
pollen trapped on clothes. A furry or grainy surface–
collected pollen loads three times higher than the flatter
fabric. The difference between towel and t-shirts (1.7
fold) was about the same, as observed by Takahashi
et al. (2008) with Japanese cedar pollen (1.9-fold).
After clothing was aired, the tape samples resulted
in tenfold higher pollen numbers compared to the
vacuumed samples. The difference was most likely
0
30
60
90
120
150
180
210
240
t-shirt trousers socks shoes
other pollen
grass pollen
pg/cm
2
n=3 n=8 n=2 n=2
Fig. 1 The amount of pollen grains on clothes after walking
through grassland (500 m). Other pollen included Rumex,
Galium, Asteraceae, Apiaceae and small amounts of Caryo-
phyllaceae, Luzula,Campanula, Urtica and Pinus pollen
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
0 500 1000 1500 2000 2500 3000 3500 4000
tight weave fabric
cotton shirt
furry fabric
pg /m
3
pg /cm
2
/h
Fig. 2 The amount of pollen on different types of clothes after
airing out in a yard during the Betula and Pinus pollen season.
Tight weave fabrics included polyamide coat and denim jacket,
and furry fabrics were terry towel, wool and fleece and cotton
included dry and moist shirts
0.0
0.5
1.0
1.5
2.0
2.5
polyamide
coat
denim
jacket
cotton
(dry)
cotton
(moist)
terry
towel
woollen
sweater
fleece
sweater
pg/cm2/h
abc
defg
d,f,g f,g g a a,b a,
b,e
g
Friedman's test
p=0.002
Fig. 3 The mean number of pollen grains on different types of
fabric after airing in a yard during the Betula and Pinus pollen
season. Letters indicate the differences between fabric types
(Friedman’s test, including Conover’s post hoc test)
Aerobiologia (2011) 27:339–343 341
123
Author's personal copy
methodological. Tape samples were taken first from
optimal locations on the top of the shoulders. Pollen
adhering to tape decreased the amount of pollen
remaining for vacuuming and in addition, the larger
vacuumed area also covered the less optimal vertical
surface of the clothes. Tape sampling is a simple
method of collecting pollen on clothes used in, for
example, forensic palynology (Flinn 1992; Wu et al.
2006). However, the texture of the fabrics revealed
the weakness of tape sampling from the quantitative
analysis standpoint. In contrast to the vacuumed
samples, less pollen adhered to tape on wool and terry
towel, probably because more pollen grains were out
of reach of the tape on the rough surfaced fabrics
compared to flat and tight weaved fabrics.
The highest pollen numbers were 340,000 pollen
grains on the shoulders of a moist shirt (tape
samples), 60,000 pollen grains on a terry towel
(vacuumed samples) and 150,000 pollen grains on
trousers after walking through grassland (tape sam-
ples). The actual numbers of pollen on clothes can be
considerably higher. Takahashi et al. (2008) counted
2–3 million pollen grains on laundry, and Zavada
et al. (2007) estimated that a large t-shirt can trap 7
million grains during a peak pollen day. These
studies, however, were carried out using a different
collection method that often leads to quantitative
differences (Frenz 1999; Piotrowska and Weryszko-
Chmielewska 2003). Pollen concentrations in the air,
local weather conditions and separate pollen produc-
ing plant species in different geographical locations
may also have an effect on the results (Giner et al.
1999; Trigo et al. 2000; Valencia-Barrera et al. 2002).
We can conclude that clothes constitute an
important route for pollen entering houses. In accor-
dance with Kiyosawa and Yoshizawa (2002) and
Takahashi et al. (2008), we were able to demonstrate
that more than half of the pollen trapped on clothes
can be removed by shaking. Although most of the
detached pollen falls to the floor in stationary indoor
air, allergic people are encouraged to shake or brush
outdoor clothing outside before entering their resi-
dences. During the peak pollen season, these clothes
should preferably be stored in a porch, outside
entrance or other place which is separated in some
way from the rooms where people spend most of their
time. Laundry should not be dried outdoors because
moist fabric may collect even more pollen than a dry
one. In addition, pollen clings to our skin and hair, as
also to pet fur. In our experimental vacuumed
samples on a dog that spent most of its day outdoors,
there were 220–240 pollen grains/cm
2
during the
Betula pollen season. As well as outdoor clothing,
pets should also be kept out of the bedroom.
Acknowledgments The study was financially supported by
the South Karelia Regional Fund of the Finnish Cultural
Foundation.
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... exceeded 1. This may be due to pollen from indoor plants (in the case of low outdoor pollen concentration) or due to pollen attached to clothing, which then entered indoor areas with a person [122,123]. Pollen persists indoors outside of the pollination period [37]. During winter, when the outdoor pollen concentration is low, pollen can accumulate indoors and may even be resuspended. ...
... Because of human outdoor activities, pollen can attach to the surface of the human body, such as the mouth, nasal cavity, or hair, as well as to glasses, masks, clothes, shoes, and pets [22,23,34,39,123,177,178]. The amount of pollen attached is related to the carrier material, the contact area between the pollen and the carrier, the background outdoor pollen concentration, and the intensity of human activities, among other things. ...
... Moreover, the dryness of clothes and the level of human activity affected the amount of pollen attached to clothes [175]. In the 2000s, a great breakthrough was made regarding pollen attachment to clothing when researchers began to evaluate both the clothing material as well as the human subjects; it was found that the pollen gradient increased from head to foot [123,180]. Most existing studies focused on the auxiliary ability of pollen on the surface of clothing, verifying that pollen is brought indoors via clothing as a carrier [34]. ...
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Pollen particles enter indoor areas through various routes, negatively affecting indoor air quality and human health. Therefore, it is important to measure the indoor and outdoor concentrations of pollen and to study the factors influencing the indoor/outdoor pollen concentration (I/O) ratio. Here, we review recent developments in pollen research, focusing on experimental studies on the I/O ratio and contributing factors, and suggest avenues for further research. Based on a literature search of 108 publications, the development, basic principles, advantages, and disadvantages of pollen samplers are summarized, and factors influencing the I/O ratio are summarized. The results showed that pollen type, ventilation, indoor ornamental plants, and human activities significantly affected the value of the I/O ratio, which ranged from 0 to 0.5. Values of I/O ratio of 0.5–1 and higher were mainly found in studies with pollen diameters ranging from 15–30 μm. A window that opened perpendicular to the dominant outdoor wind direction and a larger window opening area also increased the I/O ratio. Outdoor pollen can adhere to human surfaces and enter a room through human activity, increasing the I/O ratio. The results of this study will help other researchers to understand the state of research on pollen I/O ratios and hopefully provide suggestions for future research directions.
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... A study focusing on exposure interventions found that the level of airborne cat allergens in schools could be effectively mitigated either by pet ownership prohibition or by using school uniforms (Karlsson et al. 2004). Additional evidence has shown that clothing can be a transport vector for the mite allergens, Der f 1 and Der p 1 (Berge et al. 1998), and for allergenic pollen (Jantunen and Saarinen 2011). In summary, this body of research persuasively documents that clothing can be an important secondary source of allergenic exposures in buildings. ...
... Both biotic and abiotic material can be deposited onto clothing surfaces from various environmental sources including outdoor air and grassland (Jantunen and Saarinen 2011), residential air (Noble 2000), and public transport microenvironments (Liljegren et al. 2016). Physical contact with various indoor and outdoor surfaces and during the storage can be another pathway of particle acquisition (Clarke et al. 2015). ...
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... According to Menzel et al. (2017), the mean I/O ratio was highest in a room with mechanical ventilation and opened windows, followed by rooms with completely opened windows, and lowest in rooms with limited duration of opened windows or tilted windows. Pollen may also enter through clothing adhered to individuals affecting frequently used rooms (Jantunen & Saarinen, 2011). Pollen concentration in indoor depends on other aspects like air currents, window-to-room volume ratio, particular ventilation schemes, timing, and duration of ventilation (Jantunen & Saarinen, 2011;Menzel et al., 2017). ...
... Pollen may also enter through clothing adhered to individuals affecting frequently used rooms (Jantunen & Saarinen, 2011). Pollen concentration in indoor depends on other aspects like air currents, window-to-room volume ratio, particular ventilation schemes, timing, and duration of ventilation (Jantunen & Saarinen, 2011;Menzel et al., 2017). Pollen concentrations in the air were positively correlated with temperature and sunshine (Puc, 2012). ...
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Biological contaminants mainly consisting of living or dead microorganisms and compounds or fragments of plants and animal origin are gaining widespread research interest in recent years due to their ubiquitous presence along with their health effects on humans. Students spend a significant time of the day in educational institutions, which increases the cumulative health risk over the years. This review discusses the major biological contaminants, sampling strategies, health effects, and the factors affecting their prevalence in educational institutions. Fungi and bacteria were the most reported bio-contaminants followed by allergens and endotoxins. Exposure to bio-contaminants may result in acute and chronic respiratory diseases, infectious diseases, allergies, building-related illnesses, and even cancer. More research is needed to know the susceptibility of different age groups of students, formulation of guideline values, standard protocols for sampling, and proper diagnostic tests for diseases caused by bio-contaminants. Students should be made aware of the various aspects of indoor air quality such that they become inquisitive towards the same and become responsible for safety and hygiene.
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... A study focusing on exposure interventions found that the level of airborne cat allergens in schools could be effectively mitigated either by pet ownership prohibition or by using school uniforms (Karlsson et al. 2004). Additional evidence has shown that clothing can be a transport vector for the mite allergens, Der f 1 and Der p 1 (Berge et al. 1998), and for allergenic pollen (Jantunen and Saarinen 2011). In summary, this body of research persuasively documents that clothing can be an important secondary source of allergenic exposures in buildings. ...
... Both biotic and abiotic material can be deposited onto clothing surfaces from various environmental sources including outdoor air and grassland (Jantunen and Saarinen 2011), residential air (Noble 2000), and public transport microenvironments (Liljegren et al. 2016). Physical contact with various indoor and outdoor surfaces and during the storage can be another pathway of particle acquisition (Clarke et al. 2015). ...
Role of Clothing in Exposure to Indoor Pollutants
Chapter
  • Aug 2021
There is growing evidence that the clothing is an important source of exposure to various chemicals and particles on a daily basis. Emerging knowledge suggests that everyday clothing harbors various contaminants, which if inhaled, ingested, or dermally absorbed, could carry significant health risks. This chapter summarizes the state of the most recent knowledge regarding how clothing, during wear, influences exposure to molecular chemicals, abiotic particles, and biotic particles, including microbes and allergens. The underlying processes that govern the acquisition, retention, and transmission of clothing-associated contaminants and the consequences of these for subsequent exposures are explored. Chemicals of concern have been identified in clothing, including byproducts of their manufacture and chemicals that adhere to clothing during use and care. Analogously, clothing acts as a reservoir for biotic and abiotic particles acquired from occupational and environmental sources. Evidence suggests that while clothing can be protective by acting as a physical or chemical barrier, clothing-mediated exposures can be substantial in certain circumstances and may have adverse health consequences. This complex process is influenced by the type and history of the clothing, the nature of the contaminant, and by wear, care, and storage practices. This chapter also summarizes the most pressing knowledge gaps that are important for better quantification, prediction, and control of clothing-mediated exposures.
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... In turn, a lack of ventilation in the storeroom led to the lowest CPln. Pollen grains can also be carried inside by people or pets [21,45] and increase in magnitude when rooms are entered more often and with the increased outdoor activities individuals with access [25,46]. However, the rooms with the highest number of entering people in our study, a lecture room and a multiple office, were only linked to an average CPln. ...
Indoor Pollen Concentrations of Mountain Cedar (Juniperus ashei) during Rainy Episodes in Austin, Texas
Article
Full-text available
Standard pollen monitoring programs evaluate outdoor pollen concentrations; however, information on indoor pollen is crucial for human wellbeing as people spend most of the day in indoor environments. In this study, we investigated the differences in indoor mountain cedar pollen loads between rooms of different uses and with different ventilation at The University of Texas in Austin and focused on the effect of rainy episodes on indoor/outdoor ratios of pollen concentrations. Pollen were sampled outdoors and indoors, specifically in seven rooms and in two thermal labs with controlled ventilation, during the daytime on 6 days in 2015. We calculated daily pollen concentrations, campaign pollen integrals (CPIn, the sum of all daily pollen concentrations) and ratios between indoor and outdoor concentrations (I/O ratio). Pollen concentrations differed substantially based on features related to room use and ventilation: Whereas the highest CPIn was observed in a room characterized by a frequently opened window and door, the smallest CPIn was related to a storeroom without any windows and no forced ventilation. Our results showed that rainy episodes were linked to a higher mean I/O ratio (0.98; non-rainy episodes: 0.05). This suggests that pollen accumulated indoors and reached higher levels than outdoors. Low ratios seem to signal a low level of risk for allergic people when staying inside. However, under very high outdoor pollen concentrations, small ratios can still be associated with high indoor pollen levels. In turn, high I/O ratios are not necessarily related to a (very) high indoor exposure. Therefore, I/O ratios should be considered along with pollen concentration values for a proper risk assessment. Exposure may be higher in indoor environments during prevailing precipitation events and at the end of the pollen season of a specific species. Standardized indoor environments (e.g., thermal labs) should be included in pollen monitoring programs.
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... Moreover, exposure to allergenic biological particles from clothes has been studied for cat allergen (Almqvist et al., 1999;Almqvist et al., 2001;Damato et al., 1997;Ritz et al., 2002), dog allergen (Berge et al., 1998) and dust mites (De Lucca et al., 2000;Siebers et al., 1996), where these allergens were transported from private homes to schools and workplaces. Furthermore, pollen has been shown to accumulate on and be transported with clothes (Jantunen and Saarinen, 2011;Takahashi et al., 2008;Zavada et al., 2007). To the authors' knowledge, there has not been any studies on take-home exposure to microorganisms. ...
Work clothes as a vector for microorganisms: Accumulation, transport, and resuspension of microorganisms as demonstrated for waste collection workers
Article
Full-text available
Work clothes may act as a vector for the transport of microorganisms leading to second-hand exposure; however, this has not been studied in work environments. We investigated whether microorganisms accumulate on workers’ clothes in environments with elevated microbial exposures, and whether they are transported with the clothes and subsequently resuspended to the air. To study this, we selected waste collection workers and potential transport of bacteria and fungi to waste truck cabs via clothes, and compared the microbial communities within truck cabs, in waste collection workers’ personal exposure, and on clean T-shirts worn by the workers. Microbial communities were also investigated for the presence of potentially harmful microorganisms. Results showed that microorganisms accumulated in large quantities (GM = 3.69 × 10⁵ CFU/m²/h for bacteria, GM = 8.29 × 10⁴ CFU/m²/h for fungi) on workers’ clothes. The concentrations and species composition of airborne fungi in the truck cabs correlated significantly with the accumulation and composition of fungi on clothes and correlated to concentrations (a trend) and species composition of their personal exposures. The same patterns were not found for bacteria, indicating that work clothes to a lesser degree act as a vector for bacteria under waste collection workers’ working conditions compared to fungi. Several pathogenic or allergenic microorganisms were present, e.g.: Klebsiella oxytoca, K. pneumoniae, Proteus mirabilis, Providencia rettgeri, Pseudomonas aeruginosa, and Aspergillus fumigatus, A. glaucus, A. nidulans, A. niger, and various Penicillium species. The potential ‘take-home’ exposure to these microorganisms are of most concern for immunocompromised or atopic individuals or people with open wounds or cuts. In conclusion, the large accumulation of microorganisms on workers’ clothes combined with the overlap between fungal species for the different sample types, and the presence of pathogenic and allergenic microorganisms forms the basis for encouragement of good clothing hygiene during and post working hours.
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... Belastete Kleidungsstü cke können anschließend durch einmaliges Waschen in der Waschmaschine[71] voll ständig oder durch Ausschütteln oder Aus bürsten um ca. 70% entfernt werden[36].Kleidung ist also ein potentieller Übertra gungsvektor von Pollen aus der Außenum gebung in Innenräume; dieses Risiko kann durch einfaches Waschen oder Ausschütteln vermieden werden. ...
The influence of air pollution on pollen allergy sufferers
Article
  • Dec 2021
A multitude of consequences from global warming and environmental pollution can already be seen for nature and humans. The continuous burning of fossil fuels leads to rising temperatures and rising water levels causing extreme weather phenomena like heat waves and flooding. Increasing levels of air pollution also cause adverse health effects. This is especially important for pollen allergy sufferers because air pollution plays a central role in the interactions between pollen and humans. Today, pollen allergy sufferers are confronted with longer pollen seasons and pollen with potentially increased allergenicity. The effects for pollen allergy sufferers are an increased duration and severity of symptoms. New research results from the Medical University of Vienna prove that out of the most important air pollution parameters (particulate matter, nitrogen dioxide, sulfur dioxide, and ozone) especially ozone causes increased symptom severity in pollen allergy sufferers during the birch, grass, and ragweed pollen seasons.
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... Specific evidence has been found that clothing can serve as a carrier for biological particles and other indoor pollutants [9]. Jantunen and Saarinen [10] found that pollen can be brought into residential buildings by clothing after being worn while walking through grasslands or just being outdoors. Another research found that clothing fabrics can act as an effective pollen collector [11]. ...
Experimental study to quantify airborne particle deposition onto and resuspension from clothing using a fluorescent-tracking method
Article
The rapid spread and high level of morbidity of the SARS-CoV-2 virus during the COVID-19 pandemic has attracted considerable attention worldwide. Recent studies have shown that clothing is one of the vectors for the transport of airborne particles, including bioaerosols. This study developed a method that can both quantify the deposition of particles onto clothing and the resuspension of particles from clothing using a fluorescent-tracking technology and found that electrical tape can be used as a fluorescent particle collector on irregular clothing surfaces. Results show that 0.07%–6.61% of the fluorescent particles (FPs) previously loaded on the room flooring surfaces moved to the occupant's clothing during the 20-min sampling periods; the percentage depended on the type of activity and the range is for: office work, walking, and vacuuming. Furthermore, both the flooring type (carpet or vinyl composition tile) and flooring condition (clean or dirty) had significant effects on particle resuspension and transport to the occupant's clothing. The average particle deposition factor for carpet flooring was 2.7 (±1.4) times that for vinyl composition tile flooring, while the average particle deposition factor for dirty flooring was 2.4 (±1.6) times that for clean flooring. A multiple regression analysis shows that the activity type had the largest effect on the particle transport among all experimental variables. An additional experiment performed in a full-scale house shows that 46.8% of FPs formerly seeded on clothing resuspended from clothing and dispersed around the house during the 1-hour period of light walking at a speed of 60 steps/min.
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... They also showed that pollen retention on garments is independent of the type of fabric worn [36]. Nonetheless, other methods of recovering pollen from an array of exhibits using sterile swab sticks dampened in phenolated water [37], potassium hydroxide [38], adhesive tapes [39,40], vacuuming [41], handwashing [13], and the pinch method [42] have also been reported. ...
Identifying the Scene of a Crime Through Pollen Analysis
Article
Full-text available
The forensic analysis of pollen involves the comparison of crime scene and reference pollen samples. Successful matches are frequently used to solve time- or location-related crimes. Despite its prospects in criminal investigation, forensic palynology is still underused in casework due to inherent shortcomings such as its limited evidential weighting, scarcity of skilled palynologists dedicated to forensic casework and the laborious nature of analytical procedures. To address these challenges, the current state-of-the-art in forensic palynology is transiting from the traditional light microscopic methods that dominated the early days of palynology to more contemporary approaches like Raman spectroscopy, stable isotope analysis and DNA metabarcoding. The major challenges of these methods, however, include a lack of optimisation to forensic expectations and the unavailability of robust databases to permit accurate data interpretation, and quests to resolve these problems constitute the theme of current research. While reiterating the usefulness of pollen analysis in criminal investigation, this report recommends orthogonal testing as a way of improving the evidential weighting of forensic palynology.
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Modeling Clothing as a Vector for Transporting Airborne Particles and Pathogens across Indoor Microenvironments
Article
Full-text available
  • Apr 2022
Evidence suggests that human exposure to airborne particles and associated contaminants, including respiratory pathogens, can persist beyond a single microenvironment. By accumulating such contaminants from air, clothing may function as a transport vector and source of "secondary exposure". To investigate this function, a novel microenvironmental exposure modeling framework (ABICAM) was developed. This framework was applied to a para-occupational exposure scenario involving the deposition of viable SARS-CoV-2 in respiratory particles (0.5-20 μm) from a primary source onto clothing in a nonhealthcare setting and subsequent resuspension and secondary exposure in a car and home. Variability was assessed through Monte Carlo simulations. The total volume of infectious particles on the occupant's clothing immediately after work was 4800 μm3 (5th-95th percentiles: 870-32 000 μm3). This value was 61% (5-95%: 17-300%) of the occupant's primary inhalation exposure in the workplace while unmasked. By arrival at the occupant's home after a car commute, relatively rapid viral inactivation on cotton clothing had reduced the infectious volume on clothing by 80% (5-95%: 26-99%). Secondary inhalation exposure (after work) was low in the absence of close proximity and physical contact with contaminated clothing. In comparison, the average primary inhalation exposure in the workplace was higher by about 2-3 orders of magnitude. It remains theoretically possible that resuspension and physical contact with contaminated clothing can occasionally transmit SARS-CoV-2 between humans.
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The role of clothing fabrics as passive pollen collectors in the north-eastern United States
Article
Full-text available
The purpose of this investigation is to determine if clothing fabrics act as passive pollen collectors, and to determine if different fabrics vary with regard to the abundance and type of pollen trapped. Five of the most common fabrics in the United States (cotton, wool, polyester, silk and linen) were used to trap pollen. The pollen collecting apparatus was constructed of a 30 cm diameter circular needlepoint hoop, which vertically rotated freely, and was mounted on a dowel that was driven into the soil to chest height. Five pollen collectors, each with one of the five fabrics were placed at a collection site in rural, suburban, and urban habitats in Rhode Island for a 24 h period at weekly or biweekly intervals throughout 2002-2003. Pollen was washed from each of the fabrics and acetolysed. Total pollen per cm2 removed from each of the fabric types was estimated using a haemocytometer. The pollen types were identified, and 200 grains were counted to determine the relative abundance of the various pollen types recovered from the fabrics. Clothing fabrics act as passive pollen collectors and the flora recovered from the fabric represent the qualitative and quantitative components of the pollen rain for that specific day. There are quantitative differences among the relative abundance of pollen types from the three habitats (urban, suburban, and rural). Washing with water and a detergent eliminates a majority of the pollen from the fabrics.
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Forensic Pollen Evidence from Clothes by the Tape Adhesive Method
Article
Full-text available
  • Jun 2006
Collection and identification of pollen is becoming important in forensic applications. Many criminal cases have been reported to link suspects to the crime scene by analysis of pollen. Several methods have been used in the pollen collection and analysis, but they are expensive and tedious. Therefore, it is important to develop a simple method to collect pollen grains from clothes. We tried to recover pollen from clothing surface by using the sticky tapes method. The tape adhesive method has been widely used for sample collection for various purposes, but the efficiency of recovery of invisible pollen from clothes has rarely been reported. Therefore, to test the efficiency of the tape adhesive method in recovering pollen from clothes is important. The first author wore clothes that were made from textile S made by the mixture of cotton 60% and polyester fiber 40% to collect pollen from 26 different areas mostly in the northern part of Taiwan and then used cellophane tape D (Sirchie Finger Print Lab., Inc-No. 131LT4) to recover them from different body parts. Twenty-six pollen taxa were detected in different parts of clothes depending upon what kind of plant the first author stayed near. From the results, we concluded that the tape adhesive method is suitable in recovering pollen from clothes. We have suggested that the tape adhesive method could be part of methods for collecting pollen from clothes of suspects. It is simpler, faster and less expensive than other methods.
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A statistical approach to comparing the results from different aerobiological stations
Article
Full-text available
  • Jan 2000
The recent increase in the number of aerobiological stations means that it is possible to make comparative studies, not only to ascertain similarities and diVerences between pollen counts in diVerent places, but also to ascertain the most suitable places for them to be situated and the most adequate distance which should be established between them. To this end, we present a statistical comparison of the results obtained for the pollen of the ten most abundant taxa, as recorded in the sampling stations of Malaga and Estepona (South of Spain) during 1995± 97. The stations are 90 km apart. The variables compared were the following: mean daily concentrations (for each year and the total period studied), the mean concentration of the three years for the same date (trend) and the deviation from this mean (for each year and taken as a whole). The interannual diVerences within and between stations were taken into account as regards the association, concentration and distribution of the variables. The results of the tests applied point that signi® cant diVerences between the two stations were observed for most of the pollen types studied. Despite of this, a positive and signi® cant correlation exists between the mean daily concentrations of the diVerent taxa at the two stations, which is an important ® nding if we consider the possibility of making reliable predictions for one sampling site based on the data obtained at the other.
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Japanese cedar pollen in floating indoor house dust after a pollinating season
Article
Full-text available
Background: Approximately 16.2% of the Japanese population suffers from pollinosis. One of the forms of management is self-care (preventive care), which can be categorized as 'indoor' and 'outdoor'. Outdoor self-care is usually emphasized, but indoor self-care is also important. Considerable pollen is found in indoor dust and this is thought to be one of the factors that worsens pollinosis and enables it to persistent for a long time, even after the pollinating period has finished. Taking this into consideration, we investigated the dynamic state of indoor pollen. Methods: Floating indoor house dust was collected in Petri dishes. The amount of pollen in the house dust samples collected was measured using an LCD laboratory highly sensitive Cry j1 assay kit. Results: The results showed that, indoors, a lot of Japanese cedar pollen (JCP) was found on the floor (tatami mats, carpets), sofas and curtains. The number of JCP in living rooms peaked in April after the pollinating period and decreased gradually; however, JCP was still found indoors, even as late as the following February. Floating JCP in the house was one-tenth of the JCP levels on the floor. Floating JCP increased on days with low humidity. Air conditioning temporarily increased levels of floating JCP in houses with an air conditioner, but the level of floating JCP decreased rapidly compared with the level of that in houses without an air conditioner. Nasal signs and symptoms disappeared completely at a level of 30 floating pollen counts/day per Petri dish. Conclusion: Considerable JCP was found floating indoors with house dust after a pollinating season.
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Intrusion of airborne pollen through open windows and doors
Article
Full-text available
  • Sep 2009
The importance of the transport of pollen by air movement into houses was evaluated using six to eight simultaneously collecting rotorod-type samplers, creating either a sampler line from outdoors to inside the room, or a sampler grid inside a room. The number of incoming pollen grains was highly dependent on the outdoor concentration. The highest concentrations inside (1–2m distance) and outside (1m) the room were 600 and 3,250grains/m3, respectively, in the Betula pollen season and 1,980 and 5,080grains/m3 in the Pinus season. The pollen concentration and the indoor/outdoor (I/O) ratio decreased as the distance from the ventilation opening increased. Inside the room at a distance of 1–2m 28%, and at a distance of 3–5m 12%, of the outside concentration was recorded. In the lower part of the opening the mean proportion was 63% and in the upper part of the opening it was 40%. Efficient ventilation with two open windows increased the I/O ratio and enabled the pollen to spread throughout the room. During the Pinus pollen season 3–35% of the outdoor concentration was simultaneously recorded at six locations inside the room with two open windows and only 0.1–3.6% with one open window. At the same point in the room the I/O ratio varied from <1 to 35%, depending on the sampling conditions. Only a minor effect on the I/O ratio was found between small and large ventilation windows and the door, although it was expected that more air and pollen grains would come indoors through a larger opening.
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Seasonal and Spatial Variations of Indoor Pollen in a Hospital
Article
Full-text available
The airborne indoor pollen in a hospital of Badajoz (Spain) was monitored over two years using a personal Burkard sampler. The air was sampled in four places indoors-one closed room and one open ward on each of the ground and the third floors-and one place outdoors at the entrance to the hospital. The results were compared with data from a continuous volumetric sampler. While 32 pollen types were identified, nearly 75% of the total counts were represented by just five of them. These were: Quercus, Cupressaceae, Poaceae, Olea, and Plantago. The average indoor concentration was 25.2 grains/m(3), and the average indoor/outdoor ratio was 0.27. A strong seasonal pattern was found, with the highest levels in spring and winter, and the indoor concentrations were correlated with the outdoor one. Indoor air movement led to great homogeneity in the airborne pollen presence: the indoor results were not influenced by whether or not the room was isolated, the floor level, or the number of people in or transiting the site during sampling. The presence of ornamental vegetation in the area surrounding the building affected the indoor counts directly as sources of the pollen.
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BROUGHT-IN POLLEN INTO IND00R ENVIRONMENT BY RESIDENTS'ACTIVITIES : Study on the control of indoor pollen exposure Part2
Article
  • Aug 2002
The courses of intrusion into houses are classified as "infiltration"and"brought-in by residents'activities". The authors reported on the first subject in the previous paper. This paper reports the amount and the mechanism of cedar pollen which are brought in into dwellings or other buildings by residents' activities : those deposited on the people, those attached to the "futon", beddings, exposed to the sun, and laundry fabrics dried outdoor. The deposition on people was 10-30% of outdoor surfaces The deposited pollen on laundry can be estimated from the time stayed outside and from the outdoor pollen concentration and can be reduced to half by shaking five times before taken in. The concentration of allergens in surface dust on the"futon"can be reduced to 1/2-1/3 by beating them.
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Collection of Fiber Evidence Using a Roller Device and Adhesive Lifts
Article
  • Jan 1992
The potential for transfer of fiber evidence during the commission of a crime and the use of such evidence in criminal investigations have been well established. One of the accepted methods for collection of fiber evidence is the use of adhesive lifts, generally adhesive tape. A procedure is described for the preparation of adhesive lifts and for a roller device with which these lifts are employed. Use of the roller and lifts can substantially reduce the time associated with the collection of fiber evidence from clothing, bedding, and other items in the laboratory and at crime scenes.
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Two Routes for Pollen Entering Indoors: Ventilation and Clothes
Article
The route by which pollen enters dwellings has not been clarified. To evaluate the amount of pollen entering dwellings by ventilation and adhesion to textile products. The amount of pollen clinging to fabrics (clothes, laundry, and futon bedding) out of doors was measured by quantification of Japanese cedar pollen antigen Cry j 1. The effect of air ventilation on the amount of pollen indoors was also investigated using several neighboring unoccupied apartments with an identical layout while controlling the ventilation conditions. The amount of pollen adhering to futons was especially high. More than half of the pollen on futons or laundry remained on the surface, even after being brushed off by hand or shaken off. Vacuuming laundry and futons after airing out would be an effective way to decrease the amount of indoor pollen. A large amount of pollen entered dwellings through air ducts when the windows were closed and the ventilation fans working. Since most pollen that entered by ventilation remained near the windows, cleaning carefully and frequently near windows could reduce the amount of pollen indoors. To decrease the amount of pollen indoors, special attention must be paid to textile products and ventilation systems during the pollen season.
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Comparison Between Outdoor and Indoor Airborne Allergenic Activity
Article
Allergenic pollens are usually detected in outdoor air by using volumetric spore traps, which allow measurement of atmospheric concentration as pollen grains per m3 of air. The results of the pollen count are useful primarily for outdoor environments while most people spend most of the day indoors. The purpose of our study was to compare outdoor pollen levels with allergenic activity measured both outdoors and indoors. We used a Lanzoni spore trap to measure airborne Urticaceae pollen and filters collecting particles simultaneously indoors and outdoors and assayed each filter for Parietaria judaica allergenic activity. Samples were collected at the Allergological Service of the "A. Cardarelli" Hospital in Naples with the balcony open on some days and closed on others. Allergenic activity (ng/m3) was measured using the immunocapture RAST. With the balcony open there was no great difference between outdoor and indoor allergenic activity, but with the balcony closed there was a reduction of indoor allergenic activity of about one-third in comparison with outdoor allergenic activity. Statistical analysis (Pearson correlation test) indicated a significant correlation between outdoor allergen levels and indoor allergen levels with the balcony open (r = .4415, P < .05), but not with the balcony closed (r = .3160, P > .05); a significant correlation between outdoor pollen count and indoor allergen levels with the balcony open (r = .4809, P < .05), but not with the balcony closed (r = .3858, P > .05); and a highly significant correlation (r = .5225, P < .001) between outdoor pollen count and outdoor allergen levels. These data provide scientific evidence for the recommendation to hay fever patients to remain indoors during seasons with high levels of outdoor pollens.
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