Allergy sufferers in Toronto got a brief break from their seasonal sneezing and itchy eyes this year thanks a recent spell of cool weather. But one laboratory says as warmer temperatures make a comeback this month, so too will their symptoms. Ottawa-based Aerobiology Research Laboratories (ARL) said southern Ontario’s mild weather in March and April brought with it early pollen to start the spring. Now, after a period of cooler conditions leading into May, the mercury is set to rise again and give way to a “significant” increase in highly allergenic pollen, that could lead to “increased discomfort” and an “intense” allergy season for some. “Now it’s heating up. And so what we’re seeing is pollens were sort of delayed. They had a bit of a start, and then they said, ‘Oh no, it’s cold. I’m going to go dormant.’ And then they started up again. And now we’re getting into some of the really bad pollen types, like birch - which is highly allergenic - ash and oak,” ARL director Daniel Coates told CTV News Toronto in an interview. “By the weekend, it’s going to be a very high level for birch and ash…and then oak is starting to rise as well, and that’s extremely allergenic for people.” Coates said that while most of May is likely going to be “really bad” for allergy sufferers, he stopped short of prognosticating a “pollen apocalypse” for the months ahead. “We’re predicting more of an average season. So yes, it will be bad, but it won’t be catastrophic, per se,” he said. Beyond this month, Coates said “tree season” usually drops off by mid to late June, before grass and weed seasons set in during the summer, the latter of which he described as “horrible” in Toronto due to the large presence of ragweed. Although ARL has 30 collection sites across Canada, including one in downtown Toronto, which it uses to collect air samples and make its forecasts, Coates admits it has becoming increasingly difficult to determine exactly when the pollen seasons will start and end due, in part, to climate change. At the same time, and much to the dismay of allergy sufferers, he said the volume of pollen in Canada has jumped from 500,000 grains in the late ‘90s to just under one million grains today. “Pollen is like a business, you know, it has its ups and downs, ups and downs. But, like a business, you look at trend lines, and trend lines show that we’ve almost doubled our pollen grains nationally over the last 25 years.” Tips to mitigate your seasonal allergies Coates offered up a handful of tips to combat your seasonal allergies this spring and summer. Talk to an allergist Coates said, if you suffer from allergies, it’s important to find out what pollen you’re having a reaction to. “You feel like you have a cold 24/7, but you don’t know what you’re allergic to. Find out what you’re allergic to, and then you can better prepare programs that will actually help you to minimize the health effects of the pollen on your health.” Check the forecast Once you know what type of pollen you’re sensitive to, Coates said it’s a good practice to check when it’s in the air. “That way you can adjust your schedule. So, if you know you’re allergic to birch and it’s a high day today, don’t run outside – run on a track,” he said, adding that you can check the daily pollen forecast on the ARL website. Don’t let the outdoors in Once you’re back indoors, Coates said there are a few other tweaks you can make to keep pollen outside, including keeping pets off the bed and taking your shoes off outdoors.