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What Is Dust, And Where Does It Come From?


Using a dust mop to dust

Photo: Chiot's Run (Flickr)

Have you dusted today?

If you wipe a finger across a household surface that hasn’t been cleaned in the last few days, chances are you’ll come into contact with dust. Look around and you’ll find the stuff everywhere, from the particles floating in a sunbeam to the fine layer of grime coating TV screens, bookshelves, and car dashboards.

What Is Dust?

Dust comes from everything and, like death and taxes, you can’t avoid it. When things–shoes, rocks, plants, socks, anything at all–begin to break down, they release tiny pieces of themselves into the air.

These countless bits settle everywhere, and because matter is always coming apart, dust production is a never-ending business.


In a typical household, dust consists mainly of things such as dead insect parts, flakes of skin, food particles, and shreds of fabric. But not all dust is the product of natural decay; we create amazing quantities of dust everyday.

For example, a single puff of a cigarette contains an estimated four billion large dust particles. Industry of all sorts, from the sawing of a piece of wood to large-scale steel manufacturing, creates particular kinds of dust. In short, dust is all around, even in the air we breathe.

Because its particles are so small, dust is highly mobile. Westward winds regularly blow dust from the Sahara desert across the Atlantic and into the atmosphere above American coastal towns, where it contributes to some thrilling sunsets.

  • pbr90

    Wondering if any scientist has created an enclosed room with a desk to see how long it takes to build up a layer of dust that can be seen, and to determined what it is made of, and from where it comes, assuming the room is closed, and not being used.

    Theoretically, no activity, or windows, or shed human cells would create the stuff, but in fact, the stuff still accumulates. So where does it come from, really?

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