Allergies: spring, a season at risk

Nearly 30% of French people are affected by seasonal allergies and every spring, the same ritual is repeated: the dispersion of allergenic pollens causes red eyes, runny nose, sneezing ... the risk of exposure to grains of Pollen is, moreover, often reinforced by favorable climatic conditions and our spring habits.

SPRING, PERIOD OF POLLINATION

From the end of winter and throughout the spring, the period of reproduction of the plant species takes place. The male organs of plants then release their pollen, the reproductive element. Pollen grains are emitted in large quantities into the air to maximize the chances of reaching female flowers.

The pollination peaks may fluctuate depending on plant species, regions, years and weather conditions. A first wave of pollination usually starts at the end of winter and extends from mid-January to mid-April for the south and from late January to May for the north.

It concerns the trees and shrubs: alder, hazel, birch, charm, oak, pinaceous... A second wave intervenes from the middle of spring to summer with a shift of about 3 to 5 weeks between the north and the south of France: This is the period of grass pollen.

FAVORABLE CLIMATIC CONDITIONS

Some meteorological elements favor the dispersal of pollen grains:

• The sunlight accelerates the onset of pollination and encourages abundant emission of pollen grains.
• The absence of precipitation: the rain prevents, indeed, the dispersion of the grains of pollen. The plant keeps them then to release them at a more propitious time.
• High temperatures result in an accelerated development of plant species.
• A moderate wind favors the concentration of the pollen grains in the air by keeping them in suspension.

REFLEXES THAT PROMOTE EXPOSURE TO POLLEN

After a cold and dreary winter, when spring returns, we all tend to want to enjoy the freshness and the fresh air. We spend more time outdoors for physical activity, walking, lunch or laundry, which increases our exposure to pollen allergens.

ALL GEOGRAPHIC AREAS AFFECTED

If the points of exposure to pollen in rural areas are obvious, it should be noted that urban areas are no less affected. Indeed, pollution acts as a catalyst on pollination. The higher the CO2 emissions, the greater the presence of pollen in the air. Similarly, the change in the urban landscape, especially in the south of France, with the increasing use of plant hedges composed of cypresses, thujas and charms, presents an increased risk of spring allergies.

Source: Lescuyer Laboratory