Air Quality Index, or AQI, and PM2.5, particulate matter which measures 2.5 micrometers or less, are not the same thing. But both do refer to how polluted the air is, just in different ways. AQI, an ...

Elevated levels of PM2.5 mean the pollution may pose a health risk to all members of the public in the affected areas.

A new study analyzed space and time trends for fine particulate matter (PM2.5) in the continental United States to track the progress of regulatory actions by federal, state and local authorities ...

Despite concerns over air pollution spikes, this decades-long Danish study finds that repeated PM2.5 peaks are not linked to increased cardiovascular risk, highlighting the greater importance of ...