Ozone seeps indoors from the outdoor air. Ozone also forms indoors from operation of certain increasingly popular electronic "air purifiers," as well as printers, faxes and other office equipment. William Nazaroff, Hugo Destaillats and colleagues report that ozone can interact with ingredients in household cleaning products and air fresheners to produce a group of secondary air pollutants.
Their tests included a pine-oil cleaner, an orange-based household cleaner and a plug-in air freshener. Ozone interacted with the products to form secondary air pollutants that included formaldehyde, a known human carcinogen and mucus membrane irritant. Many other household cleaning and air freshening products contain similar chemical compounds that could interact in the same way, the researchers say in a report scheduled for publication in the July 15 issue of ACS Environmental Science & Technology.