You’ve made a fundamentally unsupported assumption, which is that all PM2.5 has equal effects on health. PM2.5 is literally just measuring the size of the pollutants in the air, nothing else. But it does matter what those particles are if we are to evaluate the health risk.
In fact, the very paper you referenced calls this out:
In this study, we found that the C-R functions differed by cause of death. The possible explanation is that within the PM2.5 concentration range from 17 to 102 ug/m3 the physical and chemical composition of the atmosphere may change, resulting in different distribution of PM2.5 components responsible for health effects across the exposure range. Previous studies have shown that the health effects caused by PM2.5 are related to its chemical components. For example, components such as organic carbon, elemental carbon, and chloride ions are associated with blood pressure; components such as zinc, cobalt, and manganese are associated with cardiovascular biomarkers. Therefore, due to the spatial variation in PM2.5 components, a single-shape C-R function is unlikely to be applicable to deaths from different causes. More studies are needed to clarify the health effects of specific components, so as to obtain a more comprehensive understanding of the C-R functions between PM2.5 and cause-specific mortality.
So in other words, the actual pollutant chemicals matter when trying to determine the health impacts. So their study is only relevant to the pollutants those people experienced, which seem to be mainly industrial air pollution like NOX.
This meta review of wild fire health risks discusses points:
- Wild fire smoke is unique compared to other PM2.5 pollution
- We don’t have sufficient data to know how wild fire smoke specifically affects health
- It matters if the smoke exposure is one day of 100 AQI or ten days of 10 AQI. The effects are non-linear as acute exposure increases.
- The effects are much more than just your lungs or heart, there’s cognitive effects as well
- The health effects can lag by up to three years, it’s not just an acute issue
- More study is needed
So don’t be too confident in any of the data so far.
I will say that the effect sizes seen in studies so far haven’t been huge. It’s not a clear and present danger type of thing. But when the AQI gets above 100 I certainly want to avoid high intensity exercise or long moderate exercise. Instead I run a HEPA filter in my trainer room.