Narrator: This is Science Today. Common household cleaners and air fresheners can emit toxic pollutants at significant levels that may lead to health risks, such as asthma, when used indoors in unventilated spaces. William Nazaroff, a professor of environmental engineering at the University of California , Berkeley , says in the past, studies have emphasized on the large and obvious sources of air pollution.
Nazaroff: This study focuses on pollution that comes from small sources, and usually we overlook small sources, but when the small sources are in close proximity to people and used in enclosed spaces, then even small rates of emission can have a significant effect.
Narrator: Nazaroff focused on chemicals found in cleaners known as ethylene-based glycol ethers and the reaction of ozone with terpenes, a class of chemicals found in pine, lemon and orange oils used in cleaners and air fresheners.
Nazaroff: I think the key thing is just to be aware that pollution isn't always out there. It's sometimes right under our nose.
Narrator: For Science Today, I'm Larissa Branin .