Global Challenges/Chemistry Solutions

Promoting Public Health: Dusting off a hidden challenge

July 19, 2010

Most indoor household dust that collects on
furniture and floors actually comes from
outdoors, a new study finds.
Credit: Wikimedia Commons
(High-resolution version)


Where does dust come from? Scientists in Arizona are reporting
a surprising answer to that question, which has puzzled and
perplexed generations of men and women confronted with layers
of dust on furniture and floors. Most of indoor dust comes from
outdoors. Their report appears in the ACS’ Environmental Science
& Technology
, a semi-monthly journal. The researchers conclude
that household dust consists of a potpourri that includes dead skin
shed by people, fibers from carpets and upholstered furniture,
and tracked-in soil and airborne particles blown in from outdoors.

With one-third of the world’s urban population living in slums, housing almost wide open to outdoor air, the global challenge of indoor dust falls into clearer focus. Listen to Dr. Layton:

“Dust can include lead, arsenic and other potentially harmful substances that migrate indoors from outside air and soil. This can be a special concern for children, who consume those substances by putting dust-contaminated toys and other objects into their mouths. It’s important for parents to keep their children’s toys as clean as possible for this reason.”

The study used data from homes in the American Midwest in a computer model to track distribution of contaminated soil and airborne particulates into residences from outdoors. That model could be used to evaluate methods for reducing contaminants in dust and associated human exposures.

“We found that over 60 percent of house dust originates outdoors. We estimate that nearly 60 percent of the arsenic in floor dust could come from arsenic in the surrounding air, with the remainder derived from tracked-in soil. While lead in the air was the chief culprit for contamination in the past, levels declined after the phase-out of leaded gasoline. Lead and arsenic derived from outdoor air and tracked soil can still present potential health problems, particularly in countries with limited controls on the emissions of those substances.”

Smart chemists. Innovative thinking.

Smart chemists. Innovative thinking. That’s the key to solving global challenges of the 21st Century. Please check our full-length podcast on Promoting Public Health. Today’s podcast was written by Michael Bernstein. I’m Adam Dylewski at the American Chemical Society in Washington.