Pollen Overload: Seasonal Allergies in a Changing Climate

Several intertwined factors influence how a plant grows and how much pollen it produces. Projected rises in two of these—regional temperatures and atmospheric carbon dioxide levels—could mean an increase in the number of people affected by seasonal allergies.© Joe Petersburger/Getty   Pollen (gold spheres) is produced by the stamens (gray), which are the male reproductive organ of flowering plants. Pollen grains are covered in proteins that assist in reproduction but also trigger allergic reactions in sensitized people.© Martin Oeggerli/Science Source Seasonal allergies in North America begin in the spring, when trees such as birch (shown), oak, and mountain cedar begin to bloom. The inconspicuous flowers of plants like these are designed not to attract pollinators but to release their pollen into the air, where it is carried by the wind.© Marcus Lindstrom/Getty Certain grasses and weeds (such as Bermuda grass, shown here magnified) trigger further allergies into the summer. Flowers that are barely visible to the naked eye can pack a major allergenic punch.© Susan M. Booker Using two different climate models, researchers modeled historical levels of ragweed pollen in Europe (frames a/b), then projected increases by 2050 (frames c/d and e/f). Some areas saw a projected fourfold jump.Source: Hamaoui-Laguel et al. (2015)11 Warming is expected to increase with increasing ...
Source: EHP Research - Category: Environmental Health Authors: Tags: Featured Focus News April 2016 Source Type: research