France Press agency , Posted on Wednesday, March 23, 2022 at 4:33 pm
The Rennes pollinarium is located on the roof of a library, and looks like any other park. This is where the fifteen species with the region’s most delicate pollen are grown, and a botanist tracks them every day, then alerts the residents.
“Right now, willow and hazel are the most resurgent,” notes Hervé Tiger, a botanist in Rennes. “In a couple of weeks, we’ll have weeds with foxtail and fragrant fluorescent.”
Before him, great planters bathing in the sunshine are home to gypsy, timothy, woolly, orchard, puffy wheat, and fragrant fluff, as well as birch, oak, hazel, and willow.
Each plant was taken from the wild, in a radius of 20 km around Rennes, at the four cardinal points. “The idea is to have more genetic diversity because not every plant emits pollen at the same time,” the botanist explains to AFP, pointing his finger at the stamens and pollen sacks. “If we shake a little bit, we see very yellow pollen, in the form of a very fine dust. That’s what causes the allergy,” he continues.
A male fertilizing component of a flower, pollen lands on the pistil of a female flower of the same species to fertilize it and form the fruit. It is made up of tiny particles a few tens of micrometers in diameter, is the thinnest and lightest, is carried by the wind, and is most likely to reach the respiratory tract and cause allergic reactions.
Every morning, Hervé Tiger reviews the flowering of selected species with allergists. “The goal is to visually monitor pollen emissions. We look to see if there are stamens and note in a small notebook the start and end date of the emission, and most importantly observe the entire first number to raise the alarm.”
– ‘Prevention tool’ –
The information is then validated by an allergist, entered into a central database in Nantes (https://www.alertepollens.org/) and published to the population. In Rennes, 1,300 patients and doctors appeared in the database, and registration is free. “Every area has its alerts, because allergenic plants aren’t necessarily the same everywhere,” the gardener specifies.
France has twenty species of pollen, four of which are in the process of opening. It first started working in Nantes in 2012. Allergists have created this “sentinel” tool, believing that there is a significant difference between the symptoms observed in their patients (rhinitis, asthma, conjunctivitis, etc.) and pollen detected by sensors. The atmosphere in cities, which is less sensitive at the onset of emission.
“It is a very interesting preventative tool from a public health point of view,” emphasizes Mikael Poliquin, an allergist and reviewer for Rennes pollinarium. “Thanks to this, you know exactly when to take and when to stop taking an antihistamine medication. This also makes it possible to identify pollen at the origin of respiratory allergies,” he continues.
In addition, treatment given from the first gram of pollen in the air is “more effective than treatment in the midst of an allergic crisis,” the doctor adds. It stresses that “the prevalence of allergies has increased for 30 years, so that the World Health Organization has predicted that one in two people will have allergies in 2050.” In France, 10-20% of the population is allergic to pollen.
In the end, the goal is to cross the entire pollen territory with about a hundred buildings.
“Global warming and pollution are contributing to an increase in the amount of pollen in the air,” recalls Julia Maguero, who is responsible for partnerships at the Pollen Sentinel Association of France (APSF). In fact, heat prolongs pollen seasons. “People are affected more and more throughout the year while before that from February to September,” she explains, adding that “the pollution also increases the allergenic potential of pollen, which leads to more and more respiratory problems.
