Is there a monster under the bed?

The far corner under the bed may be one of the safest places in most homes for house dust to hang out. But still, it was not safe from Health Canada researchers who wanted to know what's in dust anyway?

Curious about whether dust contains harmful chemicals that could build up over time, Health Canada launched the Canadian House Dust Study led by Dr. Pat Rasmussen, who sampled dust bunnies from over 1,000 homes in 13 cities across the country between 2007 and 2010.

One of the first contaminants researchers looked at was lead. Lead is a highly toxic metal that is found naturally in the earth's crust. It is used to produce many consumer products (like pipes, cars, electronics and batteries). Lead was once used in products like paint and gas, but the Government of Canada now restricts its use in many products.

Everyone is exposed to low levels of lead through food, drinking water, air, dust, soil and some consumer products. But ongoing exposure to lead may be harmful to your health.

The results from the study provide us with a better understanding of the background levels of lead that Canadians may be exposed to in their homes. The measurements are an important starting point for future research related to lead exposure in indoor environments.

All of the homes tested had some levels of lead that could be measured in their house dust, but most homes (90%) had normal levels for a typical city environment. Higher lead levels were mostly found in older homes, mainly because of the lead paint used when they were built.

Recently, Health Canada collaborated with the United States Environmental Protection Agency (US-EPA) to better understand the distribution of lead in house dust. This collaboration involved combining lead measurements from the homes included in the Canadian House Dust Study with several smaller studies from the U.S.

This combined North American dataset supported a new US-EPA regulation that residential floor dust should not contain more than 10 micrograms of lead per square foot.

Information about lead and other metals in the Canadian House Dust Study also contributed to the development of the Home Biome project, a global house dust study led by Northumbria University in the United Kingdom.

The best way to reduce lead exposure in your home is to keep the dust bunnies away. Dusting, vacuuming and wet-mopping your house regularly will help keep dust levels down in your home.

We’re not done looking at dust! Now that the samples have been tested for lead, Health Canada researchers are measuring other metals including zinc, cadmium and nickel, and contaminants like flame retardants and plasticizers.

If you’re concerned about lead in your home, learn more about how to reduce your exposure to lead.