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Many governments have imposed the public use of face masks and they are now moving towards enforcing disposable masks to abate COVID-19 transmission. While disposable masks consistently provide higher protection, they also carry multiple environmental burdens, from greenhouse gases released during production to the landfilling and littering. Conversely, reusable masks’ protection can vary from >90% certified industrial masks, similar to disposable masks, to dubious homemade or artisanal masks. This work discusses the protection provided by different masks, their impact on the environment, and new proposals combining concerns about public health and sustainability.
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environments
Review
Disposable over Reusable Face Masks: Public Safety or
Environmental Disaster?
Joana C. Prata 1, *,† , Ana L. Patrício Silva 2 ,† , Armando C. Duarte 1and Teresa Rocha-Santos 1


Citation: Prata, J.C.; Silva, A.L.P.;
Duarte, A.C.; Rocha-Santos, T.
Disposable over Reusable Face Masks:
Public Safety or Environmental
Disaster? Environments 2021,8, 31.
https://doi.org/10.3390/environments
8040031
Academic Editors: Göran Finnveden
and Dimitrios Komilis
Received: 22 February 2021
Accepted: 11 April 2021
Published: 13 April 2021
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Attribution (CC BY) license (https://
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4.0/).
1Centre for Environmental and Marine Studies (CESAM) & Department of Chemistry, University of Aveiro,
3810-193 Aveiro, Portugal; aduarte@ua.pt (A.C.D.); ter.alex@ua.pt (T.R.-S.)
2Centre for Environmental and Marine Studies (CESAM) & Department of Biology, University of Aveiro,
3810-193 Aveiro, Portugal; ana.luisa.silva@ua.pt
*Correspondence: pratajc@ua.pt
These authors contributed equally to this work.
Abstract:
Many governments have imposed the public use of face masks and they are now moving
towards enforcing disposable masks to abate COVID-19 transmission. While disposable masks consistently
provide higher protection, they also carry multiple environmental burdens, from greenhouse gases released
during production to the landfilling and littering. Conversely, reusable masks’ protection can vary from
>90% certified industrial masks, similar to disposable masks, to dubious homemade or artisanal masks.
This work discusses the protection provided by different masks, their impact on the environment, and
new proposals combining concerns about public health and sustainability.
Keywords:
SARS-CoV-2; personal protective equipment (PPE), cloth masks; fabric masks; surgical
masks; medical masks; respirators
1. Introduction
The COVID-19 pandemic, transmitted by respiratory droplets [
1
], increased the global
demand for face masks (herein masks) used by healthcare professional and the general
population as a measure to reduce viral transmission, in pair with social distancing and
hygiene. Depending on cultural and economic factors, disposable or reusable masks have
been voluntarily or compulsory adopted by the public [
2
]. Disposable masks refer to
loose-fitting surgical masks and well-fitted respirators (e.g., N95) with filtration efficiencies
characterized as FFP1 (80%), to FFP2 (94%), and FFP3 (99%) in Europe and N95 (95%), to
N99 (99%), and N100 (100%) in the US [
3
]. Disposable masks are made of polypropylene
(PP) and high-density polyethylene (HDPE) used in the production of nonwoven fabrics
using a melt-blown process [
4
,
5
]. Some of these FFP devices are classified as reusable
(marked with “R”) [
6
]. Conversely, reusable textile masks are highly available at low-
cost, varying in quality from homemade or artisanal, to industrial productions subjected
to certification. However, the rise in virus variants with increased transmissibility [
7
]
raised concerns over the public use of reusable masks, considering the wide variation
in protection efficiency. For instance, only 20% of over 3000 certified reusable masks in
Portugal had filtration efficiencies >90% [
8
]. Facing these new strains while attempting
to avoid economic disruption caused by lockdowns and the overloading of public health
systems, many countries (e.g., France, Austria, and Germany) are enforcing the use of
disposable masks in numerous public spaces [
9
]. Restrictions on the use of reusable masks
in public spaces have not considered their diversity and variable protection. Considering
the estimated global use of 129 billion disposable masks per month [
10
], it is urgent to
understand the scientific foundations supporting the use of disposable over reusable
masks, the repercussions of these measures, and potential workarounds which can favor
sustainability without compromising public health. This manuscript provides an overview
on protection efficiency, environmental impacts, and recommendations on disposable and
reusable masks for public use.
Environments 2021,8, 31. https://doi.org/10.3390/environments8040031 https://www.mdpi.com/journal/environments
Environments 2021,8, 31 2 of 10
2. Protection Efficiency of Disposable and Reusable Masks
Transmission of SARS-CoV-2 mainly occurs through airborne droplets (5–10
µ
m)
and aerosols (
5
µ
m), including from asymptomatic individuals or before the onset of
disease [
11
]. Masks can reduce the release of particles and protect the wearer [
11
]. After a
first stage of global personal protective equipment (PPE) shortage, public use of masks has
been recommended or enforced in several countries to prevent community transmission of
SARS-CoV-2 virus [
12
]. Indeed, no coronavirus could be detected in respiratory droplets
and aerosols of patients wearing surgical masks compared to 30–40% of samples of patients
without masks [
13
]. Community mask use to reduce COVID-19 transmission is supported
by a study following over 300,000 individuals in the US [
14
] and reduced household
transmission in Beijing, China [
15
]. While mask use became the norm, the protection
provided by different solutions has only recently attracted governmental attention.
Studies on the efficiency and protection conferred by masks are conducted in three
major types: reusable (or cloth) masks, surgical masks, and respirators. For Influenza virus,
also transmitted by respiratory droplets and aerosols, both respirators (N95) and surgical
masks were effective in preventing the spread of the virus from infected patients [16] and
in preventing infection of healthcare workers working in outpatient settings [
17
]. While all
masks are protective for Influenza, homemade masks produced from tea clothes provided
two times less protection than surgical masks and 50 times less than FFP2 respirators [
18
].
Similarly, surgical masks presented better filtration efficiency and generally reduced the
total amount of microorganisms expelled by coughing, compared to homemade masks
of different materials [
19
]. For COVID-19, a surgical mask barrier significantly reduced
transmission or produced fewer clinical manifestations in Golden Syrian Hamster [
20
]. The
Centers for Disease Control and Prevention (CDC) recommends general use of cloth masks,
ideally of multiple layers of high-thread-count textiles, which can block up to 50–70% of
fine droplets and particles and are reported to reduce transmission in multiple settings [
21
].
However, a metanalysis of betacoronavirus (including SARS-CoV-2) concludes that, while
all masks are effective at preventing transmission, respirators (e.g., N95) are more protective
than disposable medical masks or reusable cotton masks (12–16 layers) [
22
]. In summary,
all masks can contribute to the reduction of COVID-19 transmission, but higher protection
can be achieved by using respirators, followed by surgical masks, and finally reusable or
cloth masks.
Compared to no mask, a modeling study showed that even moderately effective masks
(50%) worn by 80% of the population could prevent 17–45% of deaths over 2 months in
New York, US [
23
]. Thus, reusable masks, even if moderately effective, can be a useful tool
to control the pandemic, especially when coupled with social distancing and hand hygiene.
Moreover, most works have not considered the diversity of reusable masks available in
regard to their quality. Recommendations regarding homemade mask making include
selection of proper fabrics, using multiple layers (>2–3), choosing a design with a proper
seal around the face, and using fitting ear loops [24]. A review on cloth masks found that,
generally, textiles >300 TPI (threads per inch) had filtration efficiencies above 80% and rec-
ommends the use of cotton or flannel of at least 100 TPI in at least two layers [
25
]. Well-fitted
multilayer masks combining a layer of 600 TPI cotton with two layers of silk, two layers of
chiffon, or one layer of flannel, by providing physical and electrostatic filtering, produced
efficiencies of >90%, comparable to those achieved by N95 respirators [
26
]. Additionally,
humidity released by breathing (i.e., 99% relative humidity) increases particle capture in
100% cotton fabrics, increasing filtration efficiency by 63% for 825 nm particles [
27
]. These
characteristics should also be tested in terms of wearability, such comfort, breathing effort,
and thermal conductivity, to ensure extended use without removal [
28
]. Thus, reusable
masks can provide effective and reliable protection comparable to disposable masks if
produced following rigid quality standards. Testing standards for disposable masks can be
applied to reusable masks (e.g., EN 14683:2019+AC:2019; see Reference [
29
]). Moreover,
certified reusable masks generally have efficiencies of filtration of 3
µ
m particles >70% or
>90%—in the last case, similar to surgical masks [30].
Environments 2021,8, 31 3 of 10
The efficiency of masks also depends on their correct use. Reusable masks may be
subjected to longer periods of use, multiple reuses without cleaning, ineffective cleaning
procedures, or decreased protection by exceeding the recommended number of washings.
Similarly, disposable masks, which should be used for 3–4 h, can be used for longer periods,
improperly stored (e.g., in pockets), and reused. For both, incorrect use and manipulation
can increase the risk of transmission. Besides filtration efficiency and use, the design of
both disposable and reusable masks should reduce face-seal leakage (i.e., by proper sealing
around the face), preventing the inward leakage of ambient aerosols and thus exposure to
infectious agents. For instance, N95 respirators present lower inward leakage compared
to generally loose-fitting surgical masks [
31
]. Face-seal leakage highly influences mask
performance, which is not often accounted for when assessing the efficiency of facemask
materials, with increased ventilation resistance and mask gap dimensions hindering pro-
tection (e.g., gaps of 1.5% of mask area can result in a 20% bypass of unfiltered air) [
32
].
Therefore, both disposable and reusable masks should be designed to reduce face-seal
leakage. Reusable masks have the additional problem of including homemade or artisanal
masks with varying efficiencies and not complying with quality standards. When it comes
to selecting face masks, design and fashion of reusable masks often outweigh functionally
in the consumer’s eyes. Additionally, reusable masks may be preferred by lower income
families due to their low-cost, as they can be 3.7 times cheaper than disposable masks [
33
].
In Portugal, the monthly cost of wearing two FFP2 masks per day (0.7–1.9
, [
34
]) is 42–114
per person. Therefore, the obligatory use of FFP2 masks increases social injustices in the
access to public and workspaces, while further straining the budget of low-income families.
3. Environmental Impact of Disposable and Reusable Masks
Reusable masks have been recommended as safe and ecofriendly alternatives [
35
],
with the implementation of the obligatory use of disposable masks worsening environ-
mental problems, from production to disposal. However, the environmental impact of
reusable masks relies on their type and the use behavior and mask choice by common
citizens (i.e., reusability, times of reuse, type of washing, and use of filters or not). For
instance, in an estimation based on UK yearly use of masks, Allison et al. [
33
] reported
similar environmental footprint between of reusable masks to the surgical masks, when
considering the use of filters and manual washing of reusable masks (
1.50
×
10
9
kg CO
2
eq), but lower in reusable masks without filters and machine washed (1.7
×
10
8
kg CO
2
eq).
Conversely, reusable masks without filters and machine-washed have a greater water use
than disposable masks, due to the washing process (7.5
×
10
8
vs. 1.4
×
10
8
m
3
). Greenhouse
gas (GHG) emissions of producing cotton cloth masks are similar to surgical masks (~0.06
kg CO
2
eq/pcs), but increases to 6.92 kg CO
2
eq/pcs considering washing (as reviewed
by Reference [
36
]). However, the estimation of cotton cloth masks has not considered the
transportation emission that is accounted for surgical masks. However, if a reusable mask
could be used for 183 times (without the use of disposable filters and considering cleaning
in the washing machine with regular clothes), the environmental footprint would go down
to 0.04 kg CO
2
eq [
36
]. However, the cumulative effects of washing can contribute to the
degradation of the mask material and reduced protection. Reusable masks can be made of
synthetic materials (e.g., polyester), which can reduce emissions and improve the number
of reuses. In addition, an adequate use and cleaning of reusable masks seems to reduce
waste by 85% and have a lower impact on climate change by 3.5 times, while also being 3.7
times cheaper [
33
]. However, information regarding fiber release during washing and their
final disposal is still lacking [
37
]. After use, both disposable or reusable masks should be
disposed of as municipal solid waste, ideally double-bagged, to be preferably incinerated
or landfilled [
38
]. Alternatively, a new waste stream can be created to collect and treat PPE,
reducing the amount of litter requiring treatment [
39
]. While incineration (800–1000
C)
decontaminates waste, with potential for energy production, these infrastructures may
already be overburdened by the growing medical waste [
40
]. Most COVID-19 household
waste is being landfilled [
41
] or, worse, discarded in open landfills in countries with limited
Environments 2021,8, 31 4 of 10
resources for proper waste management (e.g., Thailand, Philippines, and India), creating
both an environmental and public health problems [
42
]. In addition to the release of green-
house gases, landfilling of wastes may generate microplastics which are present in landfill
leachates and may be released to the surrounding environment [
43
]. In landfills’ anaerobic
environments, plastics from masks degrade forming microplastics due to variations in
temperature and pH, physical stress, and competitions, as well as action of microbiological
activity, which contributes to a progressive degradation and formation of microplastics [
43
],
while degradation in open dumps occurs from sunlight exposure and methanotrophic
microorganisms’ activity at a faster rate than in soil [
44
,
45
]. Recycling of PPE is challenging
because it may require previous decontamination (e.g., by UV light; see Reference [
46
]) and
because items are composed of multiple polymer types which cannot be easily separated
by routine grinding and remelting. Other recycling solutions can be applied to masks,
such as in the production of thermoset composites, using a crosslinking compatibilizer
agent to overcome the presence of multiple polymer types [
47
] or by thermal-recycling
producing feedstock containing useful chemicals or liquid fuels, which then can be used in
the production of other materials or as energy [
48
,
49
]. These solutions could pair public
health measures with the progression towards a circular economy less reliant on landfilling.
In addition to challenges posed by waste management, many masks are littered and
released directly to the environment (Figure 1). In Morocco, 9% of survey respondents
admitted to disposing of masks in public spaces [
50
], while littered PPE dominated by
masks has been found in urban areas with densities of 0.001 item m
2
in Canada [
51
] and
<0.3 item m
2
in Kenya [
52
]. While densities are dependent on sampling areas (e.g., higher
concentrations can be found near hospitals, [
51
]), littered items can vary with culture, with
disposable masks being a less relevant category of COVID-related litter in South Africa, due
to the widespread use of reusable cotton masks [
2
]. Beaches, which improved in quality at
the beginning of the pandemic [
53
], are now tainted with PPE, with this category compris-
ing up to 55.1% of anthropogenic beach litter in urban beaches in Kenya [
52
]. Conversely,
this litter is not found in coastal surface trawls, suggesting preferential accumulation on
beaches or the seabed after sinking [
52
]. PPE is also transported by rivers, comprising
16.0% of items in Jakarta rivers from March to April of 2020, with a high predominance of
facemasks (9.8%) [
54
]. Moreover, urban infrastructures are being burdened by PPE, with
littering and incorrect disposal into wastewater systems increasing maintenance costs by
$250 million a year in Canada [
55
]. The fate of littered PPE depends on their characteristics
in the environment, varying with brands and products, such as polymer density [
56
].
Degradation of nonwoven materials is likely to generate synthetic micro- and nanofibers
when exposed to environmental conditions [
56
], as fibers are released during mask use and
even potentially inhaled [
57
]. In the environment, weathering of plastics mainly occurs by
photo-oxidation by exposure to solar UV radiation, and at a slower rate by biodegradation
and hydrolysis, while posterior mechanical forces can lead to the formation of cracks
and fragmentation or delamination of smaller pieces, originating microplastics which
accumulate in the environment [
58
]. While larger plastics can lead to entanglement and
starvation after ingestion, microplastics can cause oxidative stress originating mortality,
reproductive failure, and decrease growth and feeding, in addition to being vectors to other
contaminants and microorganisms, having a negative impact on ecosystems [59].
Environments 2021,8, 31 5 of 10
Figure 1.
Incorrect disposal of masks observed in Portugal: (
a
) disposable masks on a beach and (
b
) reusable mask on an
urban street.
4. Recommendations on the Use of Disposable and Reusable Masks
As previously discussed, surgical masks and respirators consistently performed better
than tested reusable masks. While this supports the phasing of reusable masks, perfor-
mance and reliability also varies within categories (i.e., from artisanal to certified industrial
reusable masks), and many misuses are shared with disposable masks (e.g., multiple
reuses). Disposable masks present environmental challenges, from the release of green-
house gases during production, to the amount of waste generated or littering of public
spaces. Reusable masks are also not devoid of environmental impacts, depending on their
type and consumption patterns. Considering that both choices have different consequences,
favoring disposable or reusable masks falls over the priorities determined by governments.
More information on day-to-day protection provided by disposable and reusable masks,
conditioned by their correct use (e.g., correct face seal and proper washing), as well as
the specific environmental impacts for each type and scenario (e.g., depending on waste
treatment; microplastic release during use, washing, and disposal) can clarify the pros and
cons of each mask type. Nonetheless, various strategies can be adopted to couple public
health with long-term environmental sustainability:
Reusable masks can be produced to achieve protection efficiencies >90%, similar to
disposable masks (e.g., by using specific fabric combinations to enhance electrostatic
and physical filtering [
26
]). In Portugal, 20% of certified reusable masks already
provide protection >90% [
8
], proving that it is possible to achieve high protection effi-
ciencies. Additionally, face-seal leakage should be reduced in any mask by including
metal nose and face pinches [
60
], applying a thermoplastic rings or braces over the
mask [
61
,
62
], simply by knotting the ear loops [
62
], or improving design. Moreover,
color-changing sensors can be used to reduce the misuse of reusable masks. For in-
stance, photochromic systems can monitor the length of use of the masks by reversibly
developing color when exposed to light, while thermochromic systems can be used
to monitor proper decontamination under high temperatures, by fading color [
63
].
Additionally, antiviral materials (e.g., with non-adhesive surfaces or nanostructures),
capable of eliminating the virus on their surfaces while being safe for the wearer,
can also be developed and applied to improve the protection provided by reusable
masks [
64
]. Masks capable of inactivating SARS-CoV-2 and which retain their efficien-
cies after 50 washes are already being commercialized in Portugal [
65
]. Reusable masks
following these manufacturing recommendations can be considered equivalent to
disposable masks, but they are still dependent on correct use and cleaning. However,
the implementation of novel technologies on reusable masks should be accompanied
by the evaluation of environmental footprint. To reduce the environmental footprint
of cotton reusable masks, its major component should be cotton that is rain-fed (there-
Environments 2021,8, 31 6 of 10
fore lowering the water footprint) or organically grown cotton (lowering the carbon
footprint in the absence of pesticides and fossil fertilizers). Another solution could be
the use of recycled cotton, or other types of materials, such as polyester. An increase in
lifespan, a decrease in weight, and machine-washing procedures for cleaning (rather
than handwashing) can also reduce the environmental footprint of reusable masks.
Furthermore, the environmental impact of reusable masks (and general PPE) could be
reduced by increasing local manufacture (rather than importing/shipping supplies)
and by rationalizing their use and cleaning processes. Moreover, safe reusable masks
design must appeal to consumers to discourage the use of artisanal masks.
Production of disposable masks may follow more sustainable practices to offset their
environmental impacts. These include the use of plastics produced from renewable
resources, the use of renewable energy in the manufacturing and transportation, and
proper disposal. As an example, a successful filtering media has been of wheat gluten
biopolymer, a by-product of the food industry [
66
]. However, cost and scaling of biore-
fineries may limit these novel applications in the short-term [
67
]. Specific life-cycle
assessments can be created to assess and mitigate environmental impacts. Disposable
masks can also be reused after proper decontamination treatments while maintaining
protection efficiency, further reducing environmental impacts. For instance, decon-
tamination of N95 masks can be achieved by steaming without loss of protection [
68
].
Reuse of disposable masks could help decrease their environmental footprint and cost.
Reusable masks should be subjected to standardization similar to disposable masks.
For instance, they could follow the same ASTM Standards [
69
] or require full certi-
fication regarding their efficacy over a known number of washings, which may be
found in a national list (e.g., see Reference [
70
]). Standardization should also include
face-seal leakage requirements for both disposable and reusable masks. The use of
non-approved masks must be discouraged, which may vary from public awareness to
banning this practice by applying fines to their wearers or sellers. To ensure compli-
ance, a certification mark can be included in a visible area of the mask. In addition,
all manufacturers should provide information about the materials used in each layer
(composition, weave, weight, and thread count), the number of layers [
25
], and face-
seal leakage. Recommendations regarding decontamination must also be provided.
Instead of generally enforcing the use of disposable masks, these can be specially
enforced only in high-risk situations, such shared indoor environments (e.g., hospitals,
offices, shops, and markets), while maintaining reusable masks in lower-risk situations
(e.g., walking outside). For instance, in Austria, FFP2 masks are already required in
transit, businesses, market, and carpooling [
9
]. Similarly, the World Health Organiza-
tion recommends reusable masks, except in suspected cases, those caring for COVID-19
infected, people over 60, and those with underlying conditions which increase risk [
71
].
Moreover, the effects of the widespread use of disposable masks on daily incidence of
disease in specific situations can be modeled, maximizing their benefits.
When implementing the obligatory use of disposable masks, and considering their
higher costs, availability in stores and equal access must be guaranteed, especially for
lower-income families. Otherwise, this measure can increase social injustices. State
co-payment, such as often applied to pharmaceutical products, can be implemented
in these cases, considering the importance of masks for public health. For instance,
people over 60 or with chronic conditions in Germany will receive FFP2 masks [
9
].
Besides medical-risk groups, low-income families should also receive masks.
Masks and other PPEs should be collected in proper containers for end-of-life re-
purposing or incineration. Collection can be made in sealed specific-colored bags
for door-to-door collection or in specific bins distributed in public places, allowing
for separation and specific treatment [
39
]. PPE-bins have already been installed in
Montreal, Canada, and in Guimarães, Portugal [
72
,
73
]. Separation also allows for
specific treatment (e.g., incineration and recycling) of PEE waste.
Environments 2021,8, 31 7 of 10
Recycling of disposable masks can be achieved by thermo-recycling [
48
,
49
] or by pro-
ducing composites (e.g., conducted by companies such TerraCycle and UBQ Materials;
see References [
74
,
75
]). When recycling is not feasible, incineration is preferred since it
eliminates pathogens and avoids landfilling. Due to the large amount of waste requir-
ing incineration (e.g., medical waste), countries may need to increase their treatment
capacity, either by involving private companies or having backup incinerators, or at
least having sufficient waste-storage spaces.
Public awareness and education can provide tools on the proper use and disposal
of masks. Awareness programs can support the use of certified reusable masks and
their proper decontamination. Additionally, it may encourage the correct disposal
of masks after use and advertising for the public health and environmental dangers
of incorrect disposal of masks. Targeted actions may be applied to areas where the
incorrect disposal of masks is more likely to happen (e.g., near hospitals and grocery
shops; see Reference [51]).
Author Contributions:
J.C.P., conceptualization, project administration, visualization, writing-
original draft, and writing—review and editing. A.L.P.S., conceptualization, project administration,
visualization, writing—original draft, and writing—review and editing. A.C.D., supervision, project
administration, funding acquisition, and writing—review and editing. T.R.-S., conceptualization,
supervision, project administration, funding acquisition, and writing—review and editing. All
authors have read and agreed to the published version of the manuscript.
Funding:
Thanks are due to FCT/MCTES for the financial support (UIDP/50017/2020+UIDB/50017/2020),
through national funds. This work was also funded by Portuguese Science Foundation (FCT), through
the scholarship PD/BD/135581/2018 and the research contract CEECIND/01366/2018, under POCH
funds, co-financed by the European Social Fund and Portuguese National Funds from MEC.
Conflicts of Interest: The authors declare no conflict of interest.
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... It has been proved that wearing masks can greatly prevent the rapid spread of respiratory droplets containing SARS-CoV-2 [1]. Many countries around the world, such as Germany [2], Austria [3], Israel [4], etc., enforced or still enforce mask wearing in public places. According to the prediction of a model made by the World Health Organization, it is estimated that at least 89 million medical masks and 129 billion ordinary masks are needed each month [5]. ...
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... The main compounds of disposable masks are polypropylene, polyethylene, and other polymers such as polyesters, polyurethane, and polystyrene [157]. The surge in manufacturing and use of face masks and other PPE items raised a challenge for proper disposal in the environment [158]. ...
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... As a consequence of the mass production of masks, besides the functionality required from the health perspective, the problem of environmental sustainability has also been raised [4]. The environmental footprint of surgical and cotton masks was investigated by Schmutz et al. [5] where they intended to contribute to the design of more ecological and sustainable masks. ...
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... Threats from this emerging toxic pollutant to the ecosystem and biodiversity are a dire need for continuous research. The amount of PPE waste generated due to COVID-19 undeniably threatens the existing waste management systems and infrastructures; there is evidence of increased environmental and human health risks [15,17,18,196]. The local government, state government, federal government, coastal communities, regulatory agencies, and research institutes are significant stakeholders to take note of this emerging pollutant, and all should be incorporated into the management team [158]. Adam et al. [167] indicated the use of stakeholders for a successful single-use plastic ban. ...
... During the pandemic, a precautionary measure has been the use of personal protective equipment (PPE) to avoid virus transmission. Most PPE is used for single-use purposes and disposable PPE (e.g., surgical gowns) are often made of nonwoven fabrics containing polyethylene, polypropylene, and polyethylene terephthalate [19]. The negative effect of plastic waste generated from PPE kits, single use face masks, gloves and other equipment has disturbed the environment globally. ...
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... Until COVID-19, the use of face masks was restricted to specific professions and activities: sterile, single-use surgical-type masks used by the medical profession (Figures 1, S1 and S2, Supplementary Material); disposable KN95/P2 type masks (with and without valves) used in the construction industry to filter low levels of dust and paint fumes; and full face masks with exchangeable air filters for more hazardous work [8][9][10]. In non-professional settings, face masks were worn only in a number of East Asian countries, a practice spurred by the SARS-CoV-1 epidemic of 2003. ...
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Following the outbreak of the COVID-19 pandemic in March 2020, many governments recommended or mandated the wearing of fitted face masks to limit the transmission of the SARS-CoV-2 virus via aerosols. Concomitant with the extensive use of non-sterile, surgical-type single-use face masks (SUM) was an increase of such masks, either lost or discarded, in various environmental settings. With their low tensile strength, the spunbond and melt-blown fabrics of the SUM are prone to shredding into small pieces when impacted by lawn cutting equipment. Observations highlight the absence of smaller pieces, which are either wind-dispersed or collected by the mower’s leaf catcher and disposed together with the green waste and then enter the municipal waste stream. As proof-of-concept, experiments using a domestic lawn-mower with different height settings and different grass heights, show that 75% of all pieces of SUM fabric caught in the catcher belonged to sizes below 10 mm2, which under the influence of UV light will decay into microfibers. The implications of SUM generated microplastics are discussed.
... Until the arrival of the COVID-19 pandemic, three types of face masks were common, but restricted in their use to specific professions and activities: single-use, disposable surgical masks used by the medical profession ( Figure 1a); single-use, disposable P2/KN95 type masks (with and without valves) used in the construction industry to filter low levels of dust and paint fumes (Figure 1b); and full face masks with exchangeable air filters for more hazardous work [8][9][10][11]. Prior to COVID-19, face masks were worn in non-professional settings only in a number of Asian countries, a practice spurred by the SARS-CoV-1 epidemic of 2003 [12]. ...
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Following the outbreak of the COVID-19 pandemic in March 2020, many governments have recommended or mandated the wearing of fitted face masks to limit the transmission of the virus via aerosols. The public had, in essence, two choices: single-use, disposable surgical masks and multi-use, washable cloth masks. While the use of cloth masks has been discussed, there are, at present no baseline data that establish the actual proportions of mask types worn in the public. This paper, which presents the findings of rapid walk-through surveys of shopping venues in Albury (Southern New South Wales, Australia), demonstrates that, overall, 33.6% of masks worn by the public were cloth masks
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Different percentages of talc were added to polypropylene deriving from pristine surgical masks in a small scale extrusion equipment to confer specific rheological and thermal properties to the resulting materials. This is not a fully satisfactory solution, thus the quantity of masks has been partially replaced by a first-use polypropylene copolymer. Two selected formulations with 35 and 50 wt.% of material deriving from pristine masks and 20 wt.% of talc have been identified as suitable for the 3D printing process. Finally, the formulations were scaled up with a lab twin-screw extruder and by recycling sanitized after use masks to be as close as possible to field recycling conditions. The extruded pellets were processed to produce printing filament and finally validated as extrusion material for 3D printing. 3D printed tensile specimens were characterized for the mechanical properties and observed for their microstructure even comparing them with a commercial 3D printable material. For the first time is verified that a 3D printable extrusion material recycled from the disposable face masks can be obtained and shows comparable stiffness and strength to a commercial one.
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Post-pandemic, the use of medical supplies, such as masks, for epidemic prevention remains high. The explosive growth of medical waste during the COVID-19 pandemic has caused significant environmental problems. To alleviate this, environment-friendly epidemic prevention measures should be developed, used, and promoted. However, contradictions exist between governments, production enterprises, and medical institutions regarding the green transformation of anti-epidemic supplies. Consequently, this study aimed to investigate how to effectively guide the green transformation. Concerning masks, a tripartite evolutionary game model, consisting of governments, mask enterprises, and medical institutions, was established for the supervision of mask production and use, boundary conditions of evolutionary stabilization strategies and government regulations were analyzed, and a dynamic system model was used for the simulation analysis. This analysis revealed that the only tripartite evolutionary stability strategy is for governments to deregulate mask production, enterprises to increase eco-friendly mask production, and medical institutions to use these masks. From the comprehensive analysis, a few important findings are obtained. First, government regulation can promote the green transformation process of anti-epidemic supplies. Government should realize the green transformation of anti-epidemic supplies immediately in order to avoid severe reputation damage. Second, external parameter changes can significantly impact the strategy selection process of all players. Interestingly, it is further found that the cost benefit for using environmentally friendly masks has a great influence on whether green transformation can be achieved. Consequently, the government should establish a favorable marketplace for, and promote the development of, inexpensive, high-quality, and effective environmentally friendly masks in order to achieve the ultimate goal of green transformation of anti-epidemic supplies in the post-pandemic era.
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Filtering facepiece respirators (FFRs) and medical masks are widely used to reduce the inhalation exposure of airborne particulates and biohazardous aerosols. Their protective capacity largely depends on the fraction of these that are filtered from the incoming air volume. While the performance and physics of different filter materials have been the topic of intensive study, less well understood are the effects of mask sealing. To address this, we introduce an approach to calculate the influence of face-seal leakage on filtration ratio and fit factor based on an analytical model and a finite element method (FEM) model, both of which take into account time-dependent human respiration velocities. Using these, we calculate the filtration ratio and fit factor for a range of ventilation resistance values relevant to filter materials, 500–2500 Pa∙s∙m ⁻¹ , where the filtration ratio and fit factor are calculated as a function of the mask gap dimensions, with good agreement between analytical and numerical models. The results show that the filtration ratio and fit factor are decrease markedly with even small increases in gap area. We also calculate particle filtration rates for N95 FFRs with various ventilation resistances and two commercial FFRs exemplars. Taken together, this work underscores the critical importance of forming a tight seal around the face as a factor in mask performance, where our straightforward analytical model can be readily applied to obtain estimates of mask performance.
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Background Face masks have become commonplace across the USA because of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) epidemic. Although evidence suggests that masks help to curb the spread of the disease, there is little empirical research at the population level. We investigate the association between self-reported mask-wearing, physical distancing, and SARS-CoV-2 transmission in the USA, along with the effect of statewide mandates on mask uptake. Methods Serial cross-sectional surveys were administered via a web platform to randomly surveyed US individuals aged 13 years and older, to query self-reports of face mask-wearing. Survey responses were combined with instantaneous reproductive number (Rt) estimates from two publicly available sources, the outcome of interest. Measures of physical distancing, community demographics, and other potential sources of confounding (from publicly available sources) were also assessed. We fitted multivariate logistic regression models to estimate the association between mask-wearing and community transmission control (Rt<1). Additionally, mask-wearing in 12 states was evaluated 2 weeks before and after statewide mandates. Findings 378 207 individuals responded to the survey between June 3 and July 27, 2020, of which 4186 were excluded for missing data. We observed an increasing trend in reported mask usage across the USA, although uptake varied by geography. A logistic model controlling for physical distancing, population demographics, and other variables found that a 10% increase in self-reported mask-wearing was associated with an increased odds of transmission control (odds ratio 3·53, 95% CI 2·03–6·43). We found that communities with high reported mask-wearing and physical distancing had the highest predicted probability of transmission control. Segmented regression analysis of reported mask-wearing showed no statistically significant change in the slope after mandates were introduced; however, the upward trend in reported mask-wearing was preserved. Interpretation The widespread reported use of face masks combined with physical distancing increases the odds of SARS-CoV-2 transmission control. Self-reported mask-wearing increased separately from government mask mandates, suggesting that supplemental public health interventions are needed to maximise adoption and help to curb the ongoing epidemic. Funding Flu Lab, Google.org (via the Tides Foundation), National Institutes for Health, National Science Foundation, Morris-Singer Foundation, MOOD, Branco Weiss Fellowship, Ending Pandemics, Centers for Disease Control and Prevention (USA).
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Although landfills represent repositories for cumulative loading of plastic waste derived from households and industrial sectors, often seen as sinks, the contribution of these structures and their leachates as potential sources of microplastics to natural environments remains poorly covered. Microplastics discharged from these sites may pose greater risks to human and environmental health by adsorbed toxic and persistent hazardous chemicals. As reviewed here, landfill leachates present microplastic concentrations of 0–291 particles L⁻¹, highly variable depending on landfill conditions and methodologies adopted, while treatment of leachates can reduce these concentrations in 1–2 orders of magnitude. Nonetheless, knowledge is still scarce on the factors influencing the release of microplastics from landfills, and technology must be developed to mitigate this source of microplastics, which poses a significant challenge but is needed in order to preserve a good environmental status.
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Increased plastic uses during COVID-19 pandemic challenges efforts to reduce marine plastic debris. Despite recent observations of increased plastic-made personal protection equipment (PPE) waste in coastal areas, comparative data before and during the pandemic lacked. We present in situ monitoring data on riverine debris releases into Jakarta Bay, Indonesia, during COVID-19 pandemic relative to the 2016 baseline data. River debris at two river outlets – the Cilincing and Marunda Rivers, revealed a 5% increase in the abundance of debris and a 23-28% decrease in the weight of debris releases in March–April 2020 compared to March–April 2016, suggesting a compositional shift towards lighter debris. Plastics continued to dominate river debris at 46% (abundance) or 57% (weight). Unique to the pandemic, we observed an unprecedented presence of PPE (medical masks, gloves, hazard suits, face shields, raincoats) that accounted for 15-16% of the collected river debris of 780 ± 138 items (abundance) or 0.13 ± 0.02 tons (weight) daily. The observed increased plastic-made PPE in river outlets urges for improved medical waste management of domestic sources during the prolonged pandemic.
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The contribution of COVID-19 pandemic to marine litter pollution was studied in Mombasa, Kilifi, and Kwale counties of Kenya, in June 2020 (100 days following the first confirmed case in Kenya). Standing stock surveys were conducted in 14 streets and 21 beaches while 157 transects were surveyed for floating litter. COVID-19 related items contributed up to 16.5% of the total litter encountered along the streets. The urban beaches (Mkomani and Nyali) had the highest quantities of COVID-19 related items (55.1% and 2.6% respectively) attributable to the ability to purchase single-use products and lifestyle. Most of the recreational beaches had no COVID-19 related products which could be attributed to the presidential directive on beach closure as a COVID-19 contingency measure. No COVID-19 related litter was found in the floating litter. Generally, beach closure and cessation of movement reduced the amount of litter that leaked to the marine environment.
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The COVID-19 pandemic has resulted in an unprecedented surge of production, consumption, and disposal of personal protective equipment (PPE) including face masks, disposable gloves, and disinfectant wipes, which are often made of single use plastic. Widespread public use of these items has imposed pressure on municipalities to properly collect and dispose of potentially infectious PPE. There has been a lack of structured monitoring efforts to quantify the emerging trend of improperly disposed of PPE debris. In this study, we present a baseline monitoring survey to describe the spatial distribution of PPE debris during the COVID-19 pandemic from the metropolitan city of Toronto, Canada. Our objectives were to: (1) quantify PPE debris types among surveyed areas and; (2) identify PPE debris densities and accumulation of surveyed areas. A total of 1306 PPE debris items were documented, with the majority being disposable gloves (44%), followed by face masks (31%), and disinfecting wipes (25%). Of the face masks, 97% were designed for single use while only 3% were reusable. Of the surveyed locations, the highest daily average densities of PPE debris were recorded in the large and medium-sized grocery store parking lots and the hospital district (0.00475 items/m², 0.00160 items/m², and 0.00133 items/m² respectively). The two surveyed residential areas had the following highest PPE densities (0.00029 items/m² and 0.00027 items/m²), while the recreational trail had the lowest densities (0.00020 items/m²). Assuming a business-as-usual accumulation, an estimated 14,298 PPE items will be leaked as debris in just the surveyed areas annually. To facilitate proper disposal of PPE debris by the public we recommend development of municipal efforts to improve PPE collection methods that are informed by the described PPE waste pathways.