Narrator: This is Science Today. You may want to check the weather report before you decide to do some cleaning around the house. Environmental engineer, William Nazaroff, of the University of California, Berkeley says their research suggests that high outdoor ozone levels could create a harmful combination with chemicals called terpenes, which are found in common household cleaning products and air fresheners.
Nazaroff: If there's some smog advisory that says, “You should be indoors today because the outdoor air pollution's really going to be bad,” then that's not a good day to choose to clean your house.
Narrator: Nazaroff says ozone levels peak during the middle of summer days, and suggests cleaning near the beginning or end of the day.
Nazaroff: Doing your cleaning early in the morning or late in the afternoon or early in the evening, or doing it during a time when the weather happens to be favorable so the ozone levels aren't so high would be a smart move.
Narrator : According to the study, a person who stays in the kitchen using a moderate amount of terpene-containing products on high ozone days, would inhale about one quarter of the total daily guideline value for particulate matter. For Science Today, I'm Larissa Branin.