Time was when miners took canaries into the pits to warn them of lethal gases. Now it is not safe even to take them into the kitchen.
Canaries - and parrots, budgies and other pet birds - are dropping off their perches in kitchens in Britain and America because they are breathing poisons given off by cooking pans. And, just as when they expired in the mines, they seem to be warning their owners about a growing danger to humans.
The culprits are chemicals used on non-stick coatings such as Teflon - a brand with a reputation so spotless that its name has been applied to a Prime Minister to whom no dirt seemed to stick. But perfluorinated compounds - also used in polishes, dental cleaners, shampoos, food packaging and stainproof carpets and clothes - are the latest hazard to threaten modern living.
"Hundreds of pet birds are thought to be killed by the fumes and particles emitted from non-stick products each year," says the WWF, the wildlife charity. The Royal Society for the Protection of Animals and Britain's Parrot Society also warn of the danger, as do vets.
The birds perish within minutes when pans are overheated. DuPont, which makes Teflon, admits the danger and adds: "A simple rule of thumb is: never keep your pet bird in the kitchen."
The chemicals, which have been linked to cancers and other health concerns by animal tests and studies of workers,are being investigated by the US Environmental Protection Agency. But DuPont says: "We are very confident that our products are safe."
Environmentalists say that these concerns prove the need for proposed EU legislation to gather more safety information about chemicals on the market. But this has been watered down after an intervention by "Teflon Tony" Blair.