The so-called safe level of PM 2.5 standards are far from safe

In the US, exposure to very fine particulate matter known as PM2.5 is considered safe by the US Environmental Protection Agency’s national ambient air quality standards so long as a person breathes in an average of 12 micrograms per cubic meter of air (μg/m3) or less per day over the duration of a year. In the short term, the US considers it safe if PM2.5 levels don’t go over 35 μg/m3 within a day, so long as the yearly average comes out to 12 μg/m3 per day (in other words, a few days of higher PM2.5 here and there is acceptable, so long as there are only a few).

The “safe” levels laid out by national health agencies everywhere are inherently far from safe. “Any level of air pollution, no matter how low, is harmful to human health”

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