Here’s a finding that may come too close to home for readers who are squeamish.

It deals with plain old dust — the varieties that congregate in bunnies under your bed and insist on sitting atop the TV, especially when company is coming.

Where does that stuff come from?

Scientists in Arizona built a computerized strategy for tracking dust found in Midwestern homes to answer that question. David Layton and Paloma Beamer reported their findings in Environmental Science & Technology, a semi-monthly journal of the American Chemical Society.

You might think dust is just dust. Actually it’s a potpourri of dead human skin, fibers from carpet and furniture, tracked-in soil, decomposing bugs and assorted other stuff. If you have pets, of course, that’s another whole mess of dust ingredients.

You probably don’t want to know the full recipe. But you should know that house dust can include lead, arsenic and other toxins that migrate indoors from the outside. The researchers even found DDT, which was banned in the United States in 1972, in some of the house dust, according to Time magazine’s report of the findings.

It’s a reason to keep tots from putting dusty things in their mouths. 

"Dust in our homes...especially deep dust in our carpets and furniture, is a conglomerate of substances over the life of the home and can provide a historical record of chemicals that have entered it," Beamer told Time.

One surprise in the findings is that more than 60 percent of house dust originates outdoors and comes in through everything from the vents to the soles of your shoes.

“It goes without saying that your home will never be dust-free, but there are ways to reduce your own dust loading — and it's important that you try,” Time concluded. “Dust mites, which feed on shed skin, produce allergens that are known triggers for people suffering from asthma. Same goes for cockroach dust, especially in cities. No one needs much convincing about the wisdom of getting rid of arsenic, and the good news is that about 80% of it can be removed simply by cleaning floor dust regularly.”