Study Links Mopping with Indoor Air Pollution

Using lemon-scented cleaner to mop a floor can expose a person to as many ultrafine aerosol particles as standing next to traffic in an urban canyon of buildings for over an hour, new research finds.

The study examined the formation of organic aerosols that can occur when ingredients in common household cleaners react with chemicals in the air — in this case, mostly ozone (O₃). Despite high ventilation and relatively low ozone levels in the experiment, these aerosols formed quickly and at high levels. Because the particles are very fine, with many under 30 nm in diameter, they have the capacity to penetrate deep into the lungs, potentially causing health problems.

“People are drawn to these scented products,” says Brandon Boor, one of the study’s leaders and an assistant professor of civil engineering at Purdue Univ. “We associate the aromas with a clean atmosphere. But we do know that a lot of these scents are reactive, so if there is any ozone present, you will likely form these small, nanosized particles. It could be something that is more prevalent than we have thought.”

The researchers used a common lemon-scented cleaner to mop a 164-ft² (50 m²) room for about 15 min, monitoring the room’s air during the mopping and over the next 90 min to measure emissions from the cleaner itself and to measure particles created from reactions between the cleaner and the room’s air. The cleaner...