In the Prairies, the second most common allergy behind the universal allergy to cats is outdoor moulds, says Dr. Stuart Carr, an Edmonton-based allergist and President of the Canadian Society of Allergy and Clinical Immunology. “Any place that is a dry, agricultural sort of an environment, you’ll get a lot of mould,” explains Dr. Carr. He says moulds typically come from grain crops and other Prairie vegetation.
Unfortunately for those who are sensitive to this allergen, the levels can be very high in the late summer to the early fall and there is also a peak in the spring after the snow has melted.
In Southern Ontario the most dominant allergen is ragweed. This common plant is unique to the region, with high levels starting in mid-August through to October. “It’s a very important allergen because it causes a lot of pretty significant symptoms in people who are sensitized to ragweed,” says Dr. Carr. This could include asthma-related symptoms like wheezing, chronic coughing and shortness of breath, as well as itchy eyes and a runny nose. To further complicate matters Dr. Carr says that there has been some evidence that communities who have banned the use of pesticides have added to higher levels of ragweed in those areas.
For those living in beautiful coastal city of Vancouver, the tree-filled landscape is a nature lover’s paradise, but for those with allergies to tree pollen it’s another story. Not only does Vancouver have a high concentration of trees to begin with, but the city’s urban landscaping also plays a role in allergies. Cities often choose to plant male trees to avoid the cleanup of seeds and fruit, which female trees produce, explains horticulturalist and allergy gardening expert Thomas Ogren. The problem with this is male trees produce allergenic pollen. The most common tree pollens seen in Vancouver are alder and birch, which can cause severe reactions including asthma attacks for those with allergies to it. (While Vancouver may score poorly for allergy sufferers, it’s actually the best city in Canada for overall quality of living.)