LATimes.com reports that the California Air Resources Board (CARB) has banned popular in-home ozone air purifiers because studies show that these air purifiers can worsen respiratory conditions like asthma, which marketers claim they help to prevent.

The ban takes effect in 2009, and it's the first of its kind in the nation. Anyone caught selling the devices after a two-year phase-in period could be subject to fines starting at $1,000 a day.

CARB estimates that more than 500,000 California residents have been exposed to levels of ozone above federally recognized health standards because of air purifiers that emit ozone.

While marketers like Allen Johnston of EcoQuest air purifiers claim, ‘Ozone is both safe and effective,’ University of California inhalation toxicologist Michael Kleinman sets the record straight: ‘Ozone is a toxic contaminant, and does cause significant adverse health impacts.’

We've been telling our customers the same thing for years. If you want to clean the air in your home, select a safe, effective HEPA air purifier, especially if you have a respiratory condition like asthma or allergies.