Masks, false safety and real dangers, Part 4:
Proposed mechanisms by which
masks increase risk of COVID-19
December 7, 2020.
Completed peer-review and revised, January 8, 2021
Colleen Huber, NMD
Copyright to each article published by is retained by the author(s).
Mask “mandates” in 2020 have resulted in no reductions in incidence of COVID-19, as detected
by positive polymerase chain reaction (PCR) tests among nations or US states. Increased rates
or insignificant change in incidence of SARS-CoV-2 infections, as detected by PCR tests, have
followed mask mandates throughout the world and in US states. Masks are therefore a
possible risk factor for infection with SARS-CoV-2 and higher incidence of COVID-19 disease.
This paper examines the known physical and chemical attributes of respiration through and
involving the periphery of and inside of masks that may lead to a better understanding of the
reasons for this phenomenon of increased COVID-19 incidence following mask use.
COVID-19 incidence in masked and unmasked populations
The Council of Foreign Relations surveyed the citizens of 25 countries in mid-July, 2020. Their
question was: “Have you always worn a face mask outside the home in the last seven days?”
Yes responses ranged from the highest of 93% in Singapore to the lowest of 1% in Finland and
Denmark. In our team’s research, we examined those same countries 3 months later, in early
October 2020, regarding COVID-19 deaths and COVID-19 cases. There seemed to be no clear,
identifiable pattern with regard to deaths. However, there was a trend of the countries with
the least mask use in July 2020 showing generally fewer COVID-19 cases three months later.
Colleen Huber, NMD is a Naturopathic Medical Doctor and Naturopathic Oncologist (FNORI), writing on topics of
masks, COVID-19, cancer and nutrition.
Population data for countries and US states have shown that declared numbers of COVID-19
cases have more often increased than decreased after government “mandates” to their citizens
to wear masks in those jurisdictions. Timelines of seven countries, Israel, Peru, Philippines,
Spain, France, Hungary and Argentina, all showed no prompt impact of mask mandates on
change in number of cases or hospitalizations from COVID-19.
But all seven of those
countries showed increases in SARS-CoV-2 cases within 12 weeks following mask mandates.
Five US metropolitan areas and six US states were also examined and showed similar patterns
of increased reported SARS-CoV-2 cases. The Czech Republic showed sharply increased COVID-
19 incidence immediately following that country’s second mask mandate. The graphs discussed
were prepared using data from the COVID Tracking Project Data Download
and from Our
World In Data.
None except the Czech Republic showed a distinct inflection point from
decrease to increase or vice versa of positive PCR tests at the time of, or shortly after, a mask
mandate. The trend line of cases and hospitalizations in each jurisdiction generally increased
after some weeks following the mandate. All areas showed increases in COVID-19 cases
following mask mandates, except for New York City and Mississippi, both of which had already
begun a sharp descent in COVID-19 cases for at least two weeks prior to mask mandates and
then continued without appreciable change.
The foregoing data from The Covid Tracking Project Data Download, Our World in Data, The
Council of Foreign Relations and our research team show higher rates of positive COVID-19 PCR
tests in regions that had previous higher mask use.
The largest population-based study of facemasks and COVID-19 outcomes to date, known as
the DANMASK-19 or Danish Mask Study, was conducted in April and May, 2020, and was
released in mid-November 2020.
It enrolled 3030 participants to wear masks, and 2994 to
remain unmasked, and for one month followed 4,862 of them who were able to complete the
study. For that month, approximately one half of the participants wore masks, and the other
half did not, while they went about their daily activities, in a non-lockdown environment. The
average amount of time spent outside the home was 4.5 hours per day.
y = 37.536x + 4086.7
0 10 20 30 40 50 60 70 80 90 100
-19 cases") per 1 M
% Mask Use
Total + PCR tests per 1M pop, at 10/7/2020 from
At the end of that month, data was collected on PCR values, IgM and IgG antibodies and / or
hospital admission. Missing data and inconclusive results, patient-reported findings on home
tests and other variables limited accurate assessment of results. It was found that
approximately 2% of each group, 1.8% masked and 2.1% unmasked, were determined to have
become infected with SARS-CoV-2. The DANMASK-19 study authors confessed a prior bias in
favor of mask use, despite lack of any medical research prior to March 2020 confirming a
preventive effect of masks against any viral illnesses. According to the existing research and
meta-analyses prior to March 2020, facemasks have never been shown to be effective against
transmission of viral infections.
Nor have masks been shown to be effective specifically
against SARS-CoV-2.
The conclusion of the DANMASK-19 study was that masks did not
significantly reduce COVID-19 infection rates, and about 0.5% of each group tested positive for
other viruses. The DANMASK-19 study found, “A recommendation to wear a surgical mask
when outside the home among others did not reduce, at conventional levels of statistical
significance, incident SARS-CoV-2 infection compared with no mask recommendation.”
The data above show that regions with higher mask use either had higher rates or insignificant
change in positive COVID-19 PCR tests. It is the goal of this paper to examine the mechanisms
of mask use that may be most likely to give rise to these findings.
Proposed physical mechanisms for increased COVID-19 transmission due to mask use
A 2020 Duke University study included an examination of a cloth masks containment failure.
The mesh of certain masks served as a dispersing tool for expired respiratory droplets.
exhaled droplets from an unmasked person are known to fall to the ground quickly and at a
short distance forward from the mouth.
The Duke University study found, however, that the
mesh of the mask dispersed larger exhaled respiratory droplets “into a multitude of smaller
droplets, . . . which explains the apparent increase in droplet count relative to no mask in that
case.” Smaller particles were also found to be more likely to stay airborne longer than larger
droplets. As a result those particular cloth masks examined in the Duke University study were
considered to be “counterproductive.”
Aerosolized breath contain particles that can remain airborne for hours. “These time scales
vary from many seconds to a few hours in typical indoor settings.”
A seldom considered aspect of masking is the nozzle effect. Gaps are present around the edges
of all masks except for the most tightly fitted, and therefore possibly most suffocating,
respirators. Side gaps and brow gaps around the periphery of a mask are openings by which
exhaled and unfiltered aerosol is released into the air. As a stream of fluid (liquid or gas) is
forced by exhalation against a constricted opening, both its speed and kinetic energy increase.
Bernoulli’s equation explains the conservation of energy as a fluid is forced through a narrowed
Where ρ is the fluid density, and the kinetic energy per unit volume KE/V is ½ of mass times the
square of velocity per total Volume (V). Compression of exhaled gas inside a mask raises fluid
density compared to unmasked airspace. According to Bernoulli’s equation above, velocity and
kinetic energy as air is expelled would therefore be higher in masked than in unmasked
Pressure inside masked airspace is also higher, because there is obstruction to release of
exhaled air by the mask mesh. Pressure and volume remain inversely proportional in a closed
system with no other variables. This is explained by Boyle’s Law, which is as follows: P = k/V,
where P = pressure, k is a constant and V = volume.
The formula for gas pressure, PV = nRT, where n = the number of moles of gas, R is the
universal gas constant and T is Kelvin temperature, also shows why pressure increases inside
masked airspace on exhalation. R and T and V all stay fairly constant, but the number of moles
of gas increase as the exhaled air, and its principal components (79% nitrogen, 16% oxygen and
4% carbon dioxide) emerge from the lungs. With all other variables held constant in PV = nRT,
pressure can be expected to increase inside masked airspace on exhalation as n increases.
These mechanical considerations are applicable to masks in that a mask wraps around the sides
of the face, back toward the ears, where only small gaps remain for the unimpeded release of
exhaled breath. Similarly, gaps at the contours of the sides of the nose and under the chin
leave only narrowed gaps for unfiltered, unobstructed exhalation above and below the mask
As a result, there are side jets, back jets, a crown jet, brow jets and a downward jet that emerge
from the mask in each of those directions. Farther transmission of virus-laden fluid particles
have been found from masked individuals than from unmasked individuals, by means of
“several leakage jets, including intense backward and downwards jets that may present major
hazards,” and a “potentially dangerous leakage jet of up to several meters.” These masks “have
the potential to disperse virus-laden fluid particles by several meters.”
Backward airflow was
found to be strong with all masks and faceshields studied, compared to not masking. Schlieren
imaging revealed farther brow jets (upward flow) in surgical masks and cloth masks, 182 mm
and 203 mm respectively versus none discernible at all with no mask. With regard to side jets
and back jets, the authors found:
“It is important to be aware of this jet, to avoid a false sense of security
that may arise when standing to the side of, or behind, a person wearing a
surgical, or handmade mask or shield.”
These jets were shown to contain viral particles measuring from 0.03 to 1 microns when
expelled through the side gaps of both N-95 and surgical masks.
Unmasked individuals on the other hand are unlikely to transmit viral particles anywhere near
the distance that a masked individual can unwittingly contaminate. Oral microbial flora
dispersed by unmasked healthcare workers standing one meter from the workspace failed to
contaminate exposed plates on that surface.
A concern arises then regarding the exposure of people who are positioned next to or behind or
standing over a masked individual. Whereas unmasked individuals have been shown to have
no or short-distance viral transmission, a leakage jet of up to several meters is a condition that
makes a masked person a considerably greater risk for aerosol dispersion toward those in the
vicinity who may be concerned about their own exposure to SARS-CoV-2 or other respiratory
Proposed chemical mechanisms for increased COVID-19 susceptibility due to mask use
Low oxygen has been measured in the airspace inside a variety of masks. Available oxygen as a
percentage of available air volume decreased to less than the US Occupational Safety and
Health Administration (OSHA) required minimum of 19.5%
in less than 10 seconds of wear,
and stayed below that threshold.
A study of 53 surgeons found a decrease in saturation of
arterial pulsations (SpO2) when performing surgery while masked. Oxygen saturation
decreased significantly after the operations.
During a state of hypoxia, the body produces hypoxia-inducible factor-1 (HIF-1). HIF-1 is known
to lower T-cell function.
CD-4 T-cells have been observed to decline in this process. However,
it is essential to understand that CD-4 T-cells are known to fight viral infections.
This raises
concerns that masked persons might more easily acquire, incubate and subsequently transmit a
virus that has been the focus of intense attention, fear and concern throughout the world in
Another effect of HIF-1 is that it reduces angiotensin converting enzyme 2 (ACE2).
enzyme plays key roles in maintaining blood pressure and electrolytes and controlling
inflammation. Cells throughout the body carry receptors for ACE2, and they are especially
concentrated in lung and bronchial epithelial cells, and also present in oral and nasal mucosa.
ACE2 receptors are also the initial portal by which SARS-CoV-2 enter cells of the upper
respiratory tract. An effect of SARS-CoV-2 is that it down-regulates ACE2 receptors.
masked person with a new SARS-CoV-2 infection then would lose both ACE2 and ACE2
receptors. ACE2 is helpful to counteract damaging effects of Angiotensin II, such as
inflammation and vasoconstriction. But as ACE2 effects on the body plummet from both loss of
ACE2 and loss of receptors, the masked person with a new SARS-CoV-2 infection is especially at
risk of marked inflammation and accompanying disease severity. So pathogenic effects of
SARS-CoV-2 would be augmented by a hypoxic influence, such as masking, and therefore,
would be contraindicated in one who could become infected with this coronavirus. Therefore,
mask-induced hypoxia may make the difference between an asymptomatic or lightly
symptomatic interaction with SARS-CoV-2 in a normoxic individual, compared with a severe
case of COVID-19 in a hypoxic individual.
Carbon dioxide has also been found to rise within 30 seconds of donning a mask and remains at
high levels in masked airspace, above OSHA requirements.
Masked individuals have been
found to manifest evidence of hypercapnia,
which affects multiple body systems.
Hypercapnia immobilizes cilia, the hair-like structures we rely on to clear pathogens from the
upper airways. This leads to predisposing mask wearers to respiratory tract infections and
vulnerability to deep entry of pathogens.
The lower respiratory system is usually sterile
because of the action of the cilia that escalate debris and microorganisms up toward the mouth
and nose. Impairment of this process, such as in hypercapnia, is a risk factor for pathogenesis
and severity of respiratory infections.
Hypercapnia was found to downregulate genes related to immune response. It was found that
“hypercapnia would suppress airway epithelial innate immune response to microbial pathogens
and other inflammatory stimuli.”
Suppressive effects of hypercapnia were found on
macrophage, neutrophil and alveolar epithelial cell functions.
Another effect of masks that may have direct impact on vulnerability to COVID-19 infection is
that a mask covers some of the small portion of body surface area that would otherwise be
exposed to sunlight in winter, when seasonal coronaviruses are most prevalent. Skin exposure
to the sun is the initial mechanism for bodily production of vitamin D. Vitamin D is known to
interfere with viral replication,
and has been particularly essential as prophylaxis against
COVID-19 severity.
Population studies show that the use of masks either resulted in an increased incidence of
COVID-19 or had no impact. None of the examined jurisdictions experienced decreased
incidence of COVID-19 after the introduction of mask mandates, except two that had already
begun a sharp descent in COVID-19 cases weeks earlier. Two physical mechanisms are
proposed to directly contribute to this finding, based on current available research. The first is
scatter mechanics of dispersed respiratory droplets becoming aerosolized on collision with the
mesh of a mask on outward exhalation and then lingering in air. The second is the pressurized
and distant peripheral jets of unfiltered exhaled aerosol from the nozzled edges of a mask.
These phenomena result in viral particles lingering longer and traveling farther in airspace from
a masked person than exhaled respiratory droplets falling close to the body from the orifices of
an unmasked person. There are also chemical mechanisms for increased COVID-19 cases in
masked populations. This is likely due to immune suppression caused by hypoxic and
hypercapnic conditions, as well as acidotic, immobilized cilia in the lungs, and reduced skin
surface available to sunlight for Vitamin D production. Caution is therefore urged against use of
masks among those who wish to reduce the risk, either for themselves or others, of infection
with SARS-CoV-2 or COVID-19 disease.
C Felter, N Bussemaker. Which countries are requiring face masks? Council on Foreign Relations. Aug 4, 2020.
B Borovoy, C Huber, M Crisler. Masks, false safety and real dangers, Part 2: Microbial challenges from masks.
Primary Doctor Med J. Nov 2020.
I Miller. Mask charts. Rational Ground.
I Miller. More mask charts. Rational Ground.
The COVID Tracking Project. Data download. The Atlantic.
H Bundgaard, J Bundgaard, et al. Effectiveness of adding a mask recommendation to other public health
measures to prevent SARS-CoV-2 infection in Danish mask wearers: A randomized controlled trial. Ann Int Med.
Nov 18 2020.
J Xiao, E Shiu, et al. Nonpharmaceutical measures for pandemic influenza in non-healthcare settings personal
protective and environmental measures. Centers for Disease Control. 26(5); 2020 May.
T Jefferson, M Jones, et al. Physical interventions to interrupt or reduce the spread of respiratory viruses.
MedRxiv. 2020 Apr 7.
C Huber. Masks are neither effective nor safe: A summary of the science. Dec 2020.
J Brainard, N Jones, et al. Facemasks and similar barriers to prevent respiratory illness such as COVID19: A rapid
systematic review. MedRxiv. 2020 Apr 1.
E Fischer, M Fischer, et al. Low-cost measurement of face mask efficacy for filtering expelled droplets during
speech. Science Advances. Sep 2 2020. 6 (36).
N Mitchell, S Hunt. Surgical face masks in modern operating rooms a costly and unnecessary ritual? J Hosp Inf.
Jul 1991. 18 (3): 239-242.
M Nicas, W Nazaroff, et al. Toward understanding the risk of secondary airborne infection: Emission of
respirable pathogens. J Occup and Env Hygiene. Aug 2010. 143-154.
M Viola, B Peterson, et al. Face coverings, aerosol dispersion and mitigation of virus transmission risk.,
S Grinshpun, H Haruta, et al. Performance of an N95 filtering facepiece particular respirator and a surgical mask
during human breathing: two pathways for particle penetration. J Occup Env Hygiene. 2009; 6(10):593-603.
N Mitchell, S Hunt. Surgical face masks in modern operating rooms a costly and unnecessary ritual? J Hosp Inf.
Jul 1991. 18 (3): 239-242.
US Department of Labor, Occupational Safety & Health Administration. Confined or enclosed spaces and other
dangerous atmospheres >> Oxygen deficient or oxygen enriched atmospheres.
B Borovoy, C Huber, M Crisler. Masks, false safety and real dangers, Part 3: Hypoxia, hypercapnia and
physiological effects. PDMJ. Nov 2020.
A Beder, U Buyukkocak, et al. Preliminary report on surgical mask induced deoxygenation during major surgery.
Neurocirugia 2008. 19. 121-126.
D Lukashev, B Klebanov. Cutting edge: Hypoxia-inducible factor 1alpha and its activation- inducible short
isoform I.1 negatively regulate functions of CD4+ and CD8+ T lymphocytes. J Immun. Oct 15 2006. 177 (8). 4962
4965. DOI:
A Sant, A McMichael. Revealing the role of CD-4+ T cells in viral immunity. J Exp Med. Jul 30 2012. 209 (8).
R Zhang, H Su, et al. MiRNA let-7b promotes the development of hypoxic pulmonary hypertension by targeting
ACE2. Am J Physiol Lung Cell Mol Physiol. Mar 2019. 1; 316 (3): L547-L557. doi: 10.1152/ajplung.00387.2018
P Verdecchia, C Cavallini et al. The pivotal link between ACE2 deficiency and SARS-CoV-2 infection. Eur J Intern
Med. Jun 2020. 76: 14-20. doi: 10.1016/j.ejim.2020.04.037
B Borovoy, C Huber, M Crisler. Masks, false safety and real dangers, Part 3: Hypoxia, hypercapnia and
physiological effects. PDMJ. Nov 2020.
T Jacobson, J Kler, et al. Direct human health risks of increased atmospheric carbon dioxide. Nat Sustain. 2019.
2 (8). 691-701.
B Chandrasekaran, S Fernandes. Exercise with facemask; Are we handling a devil’s sword? A physiological
hypothesis. Nov 2020. 144 (110002). doi: 10.1016/j.mehy.2020.110002
M Joyner, D Casey. Regulation of increased blood flow (hyperemia) to muscles during exercise: a hierarchy of
competing physiological needs. Physiol Rev. Apr 2015. 95 (2). 549-601. doi: 10.1152/physrev.00035.2013.
C Kempeneers, C Seaton, et al. Ciliary functional analysis: beating a path towards standardization. Pediatr
Pulmonol. Oct 2019. 54 (10). 1627-1638.
S Casalino-Matsuda, N Wang, et al. Hypercapnia alters expression of immune response, nucleosome assembly
and lipid metabolism genes in differentiated human bronchial epithelial cells. Sep 10 2018. Sci Rep. 13508.
A Schogler, R Muster, et al. Vitamin D represses rhinovirus replication in cystic fibrosis cells by inducing LL-37.
Eur Resp J 2016. 47: 520-530. DOI: 10.1183/13993003.00665-2015
C Gunville, P Mourani, et al. The role of vitamin D in the prevention and treatment of infection. Inflamm Allergy
Drug Targets. Jul 2013. 12 (4): 239-245.
P Ilie et al. The role of vitamin D in the prevention of coronavirus disease2019 infection and mortality. Aging Clin
Exper Res.