When women from 120 middle-class homes learned their bodies contained low levels of toxic chemicals, most of them blamed chemical spills, waste dumping or secret military experiments.

They were stunned to learn the truth was closer to home. Most of their exposure came from harmless-looking plastics, flame-retardant clothing, beauty products and household cleaners.

A new study says we tend to put too much blame on environmental disasters that don't actually affect us.

"It's the consumer products" that bring chemicals into our bodies, says Kathleen Cooper, a researcher for the Canadian Environmental Law Association.

And while a study in the Journal of Health and Social Behavior was done in Cape Cod, she says exactly the same mindset prevails here. Canadians "are surprised when we talk about consumer products as a key source.

"People have this assumption that a product is on a shelf, and someone has made sure that it's safe, nothing toxic in it. And that is a false assumption."

Outdoor air pollution still matters, she noted, "but the area that is coming forward as very important is indoor exposure. We spend 80 per cent of our time indoors."

"Pollution at home has been a blind spot for society," said Rebecca Altman, a Brown University sociologist who surveyed women in Cape Cod.

The women had volunteered urine samples for a 2003 study on chemical exposure. The survey found their bodies - and also household dust - contained cancer-causing compounds and chemicals that upset human hormone systems.

"An important shift occurs in how people understand environmental pollution, its sources and possible solutions, as they learn about chemicals from everyday products that are detectable in urine samples and the household dust collecting under the sofa," she said.

These included phthalates (common plastic ingredients used in varnishes, perfumes, cosmetics and detergents); anthracenes (from paving materials and diesel); solvents (paints, varnishes, some ink); flame retardants from upholstered furniture; parabens (an anti-microbial agent in everything from jam to cosmetics); and a host of "breakdown products" left over when the body metabolizes pollutants.

The study was funded by the U.S. National Institute of Environmental Health Sciences and the National Science Foundation.

The 2003 tests on urine and household dust focused on Cape Cod because the area is known to have a higher than average rate of breast cancer.

The women were aware of some high-profile chemicals, such as bisphenol A (BPA) in some plastic bottles. But the study adds that "women do not readily connect typical household products with personal chemical exposure and related adverse health effects."