Study finds there is “no safe level” of pm2.5 air pollution

Buried lede:

> The researchers found a 1- 4 percent increased risk associated with every 10 μg/m3 increase in PM2.5.

> Put another way, Sydney has recently been experiencing increased air pollution because of bushfire smoke and, on its worst day PM2.5 surpassed the standard of 25 μg/m3 to jump to more than 500 μg/m3 in the suburb of Richmond, comparable to levels of continuous cigarette smoking. There are about 15,000 OHCAs annually in Australia so in a hypothetical situation, if there is a 10-unit increase in the daily average of PM2.5, it could lead to another 600 OHCAs resulting in 540 deaths (10% survival rate globally).

OHCA=out of hospital cardiac arrest