TORONTO - The Ontario government will examine a World Health Organization warning about a possible link between cellphones and cancer, but won't take any immediate action to warn consumers, Health Promotion Minister Margarett Best said Wednesday.

The United Nations agency reported Tuesday that the type of electromagnetic radiation emitted by cellphones and other wireless devices could possibly cause cancer.

The New Democrats want warning labels slapped on cellphones and smart phones to caution users about the possible increased risk of cancer, but Best said for now she'll consult more experts.

"I will be speaking with the Ontario chief medical officer of health, as well as Health Canada," she said. "It's a very important issue, and we will monitor and continue to monitor the evidence, the new evidence that has been brought forward."

Scientists with the WHO's International Agency for Research on Cancer classified radio frequency electromagnetic fields as "possibly carcinogenic to humans,"' based on a higher risk of glioma, a rare but often deadly form of brain tumour.

Other substances in the same category include pesticides and gasoline engine exhaust. The other categories include carcinogenic, probably carcinogenic and probably not carcinogenic.

The New Democrats said parents should not let their children use cellphones because their thinner skulls make them more vulnerable to the radiation.

"Would you let your kids play in the exhaust coming from a car?" said NDP health critic France Gelinas. "Right now they treat it as low microwaves cooking your brain slowly."

The NDP wants the warnings already printed in the books that come with mobile and smart phones to be placed on the actual phones themselves. The upgraded warning from the UN agency should prompt governments to take action to protect people, added Gelinas.

"How much more evidence do you need before you do as little as letting people know that there might be a risk, and here's how you protect yourself?" she said. "When the World Health Organization bumps it up a step, it is significant, significant enough that a government should act."

The Progressive Conservatives said the WHO report was a "warning flag," but said government should wait until the studies are completed to confirm a link between cellphones and cancer.

The Canadian Wireless Telecommunications Association, which represents most of the cellphone companies, said Tuesday that the WHO report only found a "possible" link between wireless devices and cancer.

"They were very clear that they are not saying there is a proven link between cellphones and cancer," said Marc Choma, the wireless association's director of communications. "There is no reason to put a warning on the cellphones."

A group of parents in the Barrie area who have been fighting to have WiFi turned off in schools said the WHO report gives school boards all the evidence they need to take action to protect teachers and students exposed to wireless radiation for six hours a day.

"If they already have policies in place to deal with anything that legally is called a potential hazard, they are obligated to warn any person who works in the building that the hazard exists and what the hazard is," said Rodney Palmer of the Simcoe County Safe Schools Committee. "Do we put a class 2B carcinogen in a classroom and do we do that without informed consent from the parents?"

The cancer warning isn't just about cellphones, added Palmer.

"It's WiFi, baby monitors and cordless home telephones, which all operate at 2.4(gigahertz)," he said.