Dust Is More Than Dirt
Dust is anything that breaks down into small enough particles that it can be moved by air currents outside or in your home. The dust in your home is actually a combination of dust and dirt from outside, combined with skin cells, pet dander and a number of other particles that vary from home to home.
Tiny fibers from your clothing, lint that flakes from your carpet and furniture, skin cells, fibers of human and pet hair and a number of other small particles may be found floating around your home or stuck under your furniture. The composition of dust may be complex and contain more than small particles of lint and dirt.
Paloma Beamer, Ph.D., associate professor in the school of Public Health at the University of Arizona, has spent years thinking about and studying dust. She calculates one-third of the dust in your home comes from indoor inorganic sources and two-thirds from soil and outdoor air particles tracked into your home.
The composition of dust is complex, and so is the composition of one particle. According to Andrea Ferro, Ph.D., who teaches courses in air pollution at Clarkson University in New York, a dust particle can be a simple inorganic or organic compound, but others may have an inorganic center and an organic coating.
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