Air cleaners make smog, study finds

A new study finds that using a popular process called ionization, air cleaners can actually generate ozone levels in a room that exceed the worst smog days in Los Angeles:

The devices are popular in urban areas. They are touted as getting rid of dust, pollen and other airborne particles.

Ionic air purifiers, one type of these devices, are said to work by charging airborne particles and then attracting them to metal electrodes. They emit ozone as a byproduct of this ionization process.

In a small and poorly ventilated room, the ozone adds to existing ozone and creates potentially unhealthy concentrations.

Read on over here.