Rebuttals to some of the disinformation being spread can be found on this page. Here, however, are literature reviews supporting the use of respiratory protection, in reverse order by publication date.
A Short Rabbit Trail
In regard to the droplet and airborne debate, I have used the idea of electron clouds from general chemistry to try to illuminate the flaws in that false dichotomy. This theory was developed in 1926 by Erwin Schrödinger and Werner Heisenberg, who you may have heard in pop culture related to the terms Schrödinger’s Cat and the Heisenberg Uncertainty Principle (or Walter White being called “Heisenberg” by Jesse in Breaking Bad).
The idea of an electron cloud, and similarly, electron shells, has to do with the probability of where an electron can be found in relationship to the nucleus of the atom. Since they are constantly orbiting, a map of their positions would form a three-dimensional shape around the nucleus. However, they do not remain at a constant distance from the nucleus. If they did, the electron shell shape would be a perfect sphere for the simplest of orbitals. In reality, the orbital shape is more of a fuzzy probability sphere. It can be visualized this way on a flat surface.
Think about this as an analogy to particles in a sneeze. The probability of finding particles right next to the mouth versus nine feet away is obviously much higher, as is illustrated by this photo of particles expelled by a cough.
Part of the droplet argument stems from the idea that the larger droplets will fall to the ground due to gravity, which is true. However, much of what is expelled is an aerosol, with particles that can remains suspended. In drier environments, such as during the winter, the smallest of these droplets can even desiccate before hitting a surface, leaving what is known as the droplet nuclei (a virus or bacteria) suspended in the air.
Masks and respirators for prevention of respiratory infections: a state of the science review (2024)
Besides the research itself, the authors also describe the erroneous history of using discrete variables to distinguish droplet and airborne transmission and the flaws in that thinking as illustrated above. One thing that has become apparent through the course of the pandemic is the level of simplistic, binary thinking of a large proportion of the population. I remember when I started grad school in epidemiology, one of the first things they told us was that if we couldn’t escape black and white thinking and adjust to all of the shades of gray, we should probably pursue a completely different line of study.
The authors laid out what they felt to be the flawed assumptions that have caused so much confusion:
- Absence of direct evidence in favor of airborne transmission can be taken as evidence refuting airborne transmission.
- Because contact and droplet transmission can occur only during close contact, all close-contact transmission must be contact and droplet.
- Because large droplets are smaller than the lumen of the smallest bronchioles, they can reach the key target cell for SARS-CoV-2 in the alveoli.
- Particles above 5 µm in diameter are droplets and not aerosols.
- Aerosols are produced in significant numbers from infectious patients only when aerosol-generating medical procedures (AGMPs) are done.
- Only respiratory diseases with a high R0 (such as measles) are airborne.
Further, they describe the four factors influencing mask efficacy:
- Filtration
- Fit and seal
- Breathing resistance
- Potential for contamination
They used a review study by Schmitt and Wang that illustrated how protection varies between types of masks used.
To their credit, they also looked extensively at some of the negative aspects of mask use, but also rebutted some of the claims by antimaskers. “Our review of adverse effects and harms of masks found strong evidence to refute claims by anti-mask groups that masks are dangerous to the general population. We also found that masking may be relatively contraindicated in individuals with certain medical conditions and that certain groups (notably D/deaf people) are disadvantaged when others are masked.”
Their first and final conclusions say it all. “The claim that masks don’t work is demonstrably incorrect, and appears to be based on a combination of flawed assumptions, flawed meta-analysis methods, errors of reasoning, failure to understand (or refusal to acknowledge) mechanistic evidence, and limitations in critical appraisal and evidence synthesis…the grave danger posed by ideologically driven anti-mask narratives to public and global health should be acknowledged and systematically addressed. Anti-mask sentiment is increasing, along with anti-vaccine sentiment (413), and this bodes ill for both the current and any future pandemics. While there are no simple solutions to the problem of widespread disinformation, clear and consistent messaging from public health bodies on masks and other mission-critical topics would help considerably.”
An evidence review of face masks against COVID-19 (2021)
“Our review of the literature offers evidence in favor of widespread mask use as source control to reduce community transmission…The available evidence suggests that near-universal adoption of nonmedical masks when out in public, in combination with complementary public health measures, could successfully reduce 𝑅𝑒 to below 1, thereby reducing community spread if such measures are sustained.”
Masks and Face Coverings for the Lay Public: A Narrative Update (2020)
“Masks and face coverings, if widely worn, may substantially reduce the spread of COVID-19.
The benefits of mask wearing seem to outweigh the harms when COVID-19 is spreading in a population.
Randomized trials are sparse and have not addressed the question of source control.
Psychological effects of masks are culturally framed and shape acceptance and adherence.
Mandated masking involves a tradeoff with personal freedom.”
One has to wonder why cancer centers are getting it right but other healthcare organizations are not.
“COVID-19 policies were confirmed at all 67 patient-serving NCI-designated cancer centers. 28 cancer centers (41.8%) required universal masking in at least some clinical areas, with 12 (17.9%) requiring universal masking in all areas. Only 14 (20.9%) had accurate up-to-date policies flagged on the home page of their websites. In 8 cancer centers (12.0%), policies posted on websites differed from those noted by telephone. Cancer centers were more likely to require universal masking in at least some areas if they were located in the Northeast (11 [78.6%]), had longer NCI designation duration (first quintile: 10 [83.3%]), had more program funding (first quintile: 11 [84.6%]), or had a higher care ranking (first quintile: 11 [84.6%])”
Weird how you are only able to provide a couple of examples to back up your bias..
So let’s see what the actual evidence has to say..
https://owenowenowen.substack.com/p/the-evidence-regarding-potential
You keep proving your lack of knowledge around science. I’ll respond to just the first few studies you selected.
1. Inhaled CO2 Concentration While Wearing Face Masks: A Pilot Study Using Capnography – This study is about the role of glasses in preventing COVID, showing that you don’t even bother to read them. No matter though, you wouldn’t understand anyway.
2. Possible toxicity of chronic carbon dioxide exposure associated with face mask use, particularly in pregnant women, children and adolescents – A scoping review – Heliyon is a completely worthless pay to publish rag. Further, “Concerns have been raised about the quality of the content published in this journal.” https://mjl.clarivate.com/search-results
3. Physical interventions to interrupt or reduce the spread of respiratory viruses – This Cochrane review is garbage for many reasons. https://icemsg.org/myths/myth-masks-dont-work/the-cochrane-review-on-masks/
4. Unravelling the role of the mandatory use of face covering masks for the control of SARS-CoV-2 in schools: a quasi-experimental study nested in a population-based cohort in Catalonia (Spain) – The comparison was made between two completely different population groups and is invalid just from that standpoint. Further, they don’t adjust for vaccination, air filtration, or other confounding variables. It’s limited to a very small region. Worse, they don’t have any means to assess respiratory protection outside of the school setting and this was done during a very low period of transmission in the area.
5. Bacterial and fungal isolation from face masks under the COVID-19 pandemic – This study really provides nothing of importance. The organisms found are opportunistic meaning that they won’t cause problems for most people. Overall, they are common organisms on the skin.
6. Inhaled CO2 Concentration While Wearing Face Masks: A Pilot Study Using Capnography – Another pay to publish piece. Regardless, there are a number of flaws in it that the authors cite themselves. Further, if masks work so well at blocking CO2, they should work even better at blocking viruses, which are thousands of times larger.
I’m not wasting time on any more since you have established your lack of critical thinking skills. All you have done is proven you don’t bother to read the studies, only quote what fits your narrative, and lack the education to critically assess them. It’s a lot of Dunning Kruger and hubris wrapped up in one person.