Canadian scientists believe they may have an explanation for the rise in dangerous peanut allergies. More than one per cent of Canadian children are allergic to peanuts, some so severely that even a tiny amount ingested or even touched can kill.

Because of this, many schools have banned peanuts from the premises.

The allergic reactions are triggered by two proteins found in peanuts, called — ARA H1 and ARA H2.

Peanut allergies have doubled in the past 15 years, in part due to a proliferation of products containing peanuts, even in foods such as chocolate and chili. Peanuts are also found in some cosmetic products.

Dr. Peter Vadas, an allergist at St. Michael's Hospital in Toronto, says he and his colleagues have found more than half of breastfeeding women who eat peanuts pass the proteins to their babies.

This discovery may provide an explanation for the rise in allergic reactions, even in infants as young as three months who aren't eating solid foods.

Scientists hope to create a vaccine to prevent allergies, but that's at least five years away. Even then, a vaccine won't be able to cure an allergy once it's started.

Without such a cure, it's up to manufacturers to test foods for peanut extracts and to put warning labels on packages.

The government is supposed to do its own testing. Gerry Nixon of the Canadian Food Inspection Agency told CBC News: "It would really be an impossible job for government to pretend to analyze every lot of food that is produced. It's simply not our role."