The researchers at Stockholm University have taken blood samples from indoor cats and measured the levels of brominated flame retardants, so called BFRs.
"Cats that are indoors lick their fur when they wash themselves. In the fur, there is dust, and it is almost as if the cat eats the dust. They have a very high exposure to the dust, just like a little kid that crawls around the floor and puts everything in its mouth," says Jessica Norrgran, who was in charge of the study.
The researchers vacuum cleaned the houses of a number of families with young children - and compared those contents with the blood samples from the families cats. And there was a clear link between the levels of the brominated flame retardants in the dust and in the blood sample.
The BFRs are used in a range of products, such as plastic, electronics, clothes and furniture - as a way to reduce the flammability of the product.
But as the chemicals are absorbed by our bodies, and end up staying there for a long time, Sweden was among the countries that banned the use of BFRs in the beginning of the century. Part of the problem is that many of the BFRs can have a hormon-disrupting effect.
"They interfere with our reproduction. You may find that you have difficulties in becoming pregnant or keeping the foetus. It can be devastating," says Jessica Norrgran.
It is known from before that children have higher levels of these chemicals in their blood than adults have - and it is possible that that we get it into our bodies through food. But according to this study, the health risks of the BFRs are bigger when it come to the dust in our homes. That is why your cat can be a good indicator of how big that risk actually is in your home.
On the positive side, there is something you can do about it, although for tired parents of young children it is perhaps not what you are longing to hear.
"You need to clean your house when a child is crawling around on the floor. Vacuum clean and mop," says Jessica Norrgran.