I released a blog post earlier this week about teargas after researching it further and joining with other physicians to write a letter to the Portland mayor and city council about concerns about potential longterm health effects of tear gas as well as short-term worsening of the COVID19 pandemic (resulting in potentially massive short term loss of life). I have been diving deeper into the research since that post, and am releasing a podcast with more information today.

I think sometimes the things that sicken us are hard for us to see, both as individuals and as a scientific community. It took us a long time to realize that something as ubiquitous as a cigarette was actually killing over half of its regular users. When we think of lethal interventions, a lot of us think of movies where we see people being shot. A gun is so direct and lethal and final. It’s harder to see the things that make us ill over the longer timeframe. But in my job everyday, I see people dying of these things that are very common in the community and not uniformly lethal, but they are still lethal enough to be putting the life at risk of the patient in front of me. I care for patients dying from influenza, I care for patients dying from tobacco inhalation, and other forms of breathing poor air, including the asthmatic there with a severe exacerbation from allergies and a high pollen count. What we breathe matters. Even if an intervention is not as lethal as shooting someone with a gun, even some degree of lethality needs to be weighed very heavily, especially if we are considering using it on a large population. I worry that the young woman in Ohio who was found dead two days after teargas exposure may be only a first case, and that in a few weeks, we will see a surge in COVID19 cases related to increased risk of viral infection after teargas exposure.

On the podcast, I delve into additional studies, including the history of why it has been referred to as “safe,” as well as reviewing a study from Turkey about people who had repeated exposures, which may be more consistent with the risks faced by both protesters and police officers in our communities. 

One study on “safety” does not appear to have been peer-reviewed in the medical literature (that I can find, let me know if I’m wrong!) and was done on 34 healthy police cadets and trainers with an average age of 31.7. They wore goggles to protect their eyes and were sprayed once with aerosolized capsaicin and then had lung function tests done. While there was not a difference in lung function, there was a sustained elevation in blood pressure and an increase in heart rate that was significant. This study is of too few people to be helpful (also known as “underpowered”) in answering the question about long term health effects. I found the blood pressure elevation worrisome for our country with so much cardiovascular disease. I also speculate a bit on the discussion section of this paper and its planned use to help avoid litigation.