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I've been asked by multiple media outlets about tear gas and how it affects #SARSCoV2 transmission or #COVID19 severity. I don't know. I've never had occasion to think about the effects of tear gas on respiratory virus pathogenesis during a pandemic. https://www.propublica.org/article/tear-gas-is-way-more-dangerous-than-police-let-on-especially-during-the-coronavirus-pandemic
I don't even know if tear gas and viral infection has been studied. I could only find one paper from 30 years ago indexed in PubMed, and I couldn't access it. Besides, it looks like it's probably a commentary rather than an original research article.
https://pubmed.ncbi.nlm.nih.gov/2095429/
https://pubmed.ncbi.nlm.nih.gov/2095429/
But from @lisalsong @propublica's reporting, it certainly sounds like tear gas has some pretty predictable consequences. A few studies show that, while tear gas is *USUALLY* not lethal, it is linked to long-term respiratory problems: https://academic.oup.com/milmed/article/179/7/793/4259353#101149356
It's linked to chronic disease in multiple organs, including skin, respiratory, ocular, cardiovascular, gastrointestinal, and reproductive systems. https://nyaspubs.onlinelibrary.wiley.com/doi/full/10.1111/nyas.13141
One study estimated the risk of severe adverse clinical effects from tear gas to be ~7%. So if you are exposing huge numbers of people in an urban center to tear gas (either CS or pepper spray), you're going to see lots of adverse effects. https://www.tandfonline.com/doi/full/10.3109/10903127.2014.891063
It's puzzling to me that tear gas is considered such a great non-lethal riot control intervention by police on their own citizens, when its use in military combat is a war crime per the Geneva Convention prohibiting chemical weapons. https://www.pri.org/stories/2019-07-31/tear-gas-has-been-banned-warfare-why-do-police-still-use-it
Furthermore, it's easy to imagine how tear gas could exacerbate other chronic conditions, especially with prolonged exposure. Triggering an asthma attack could be lethal. Even without a pandemic in the background, tear gas can be debilitating and sometimes lethal.
In fact, ProPublica reports that yesterday, an inmate at a detention center in Brooklyn died of a heart attack after being pepper sprayed. https://www.nydailynews.com/new-york/ny-mdc-inmate-heart-attack-20200604-rrvzzt23tjc4th5shycsndzmpi-story.html
But even though the risks regarding how tear gas could enhance #SARSCoV2 transmission and #COVID19 morbidity are unknown, it's not a stretch to surmise that tear gas exposure won't lead to good clinical COVID-19 outcomes in people infected in the days to come.
This doesn't even just apply to protestors. People who are present at their homes and businesses in the vicinity of tear gas dispersal will also suffer these adverse consequences. Tear gases are oily compounds that don't immediately disappear from the environment.
If people are exposed to tear gas, whether at protests or just as bystanders existing in the communities where gas is used, they could cough more and produce more respiratory droplets, increasing transmission risk.
If people are being chronically exposed to substances that increase co-morbidities known to be risks for severe #COVID19, then their use for crowd control is at best reckless. Tear gases are not "non-lethal" substances if they actually contribute significantly to people's deaths.
How this will play out remains to be seen with regard to the #COVID19 pandemic, but at the very least police cannot justify the use of tear gas on crowds of the citizens in their own communities that they are supposed to theoretically protect and serve.
The protests are occurring because police violence and the racism underlying it is itself a public health crisis, and I seriously doubt that law enforcement will voluntarily stop using supposedly "non-lethal" measures like tear gas.
If tear gas is sufficiently inhumane that it cannot be used against enemy combatants during a war, why is it okay for law enforcement to use it on our own communities? It's absolutely not. I challenge any police dept to justify its use given its potential to harm public health.
We need to seriously consider legal means of prohibiting its use against our own people by the very people who should be trusted to protect and serve us. Tear gas is not safe and it's not non-lethal. It's a threat to public health on multiple fronts.
