Ragweed pollen levels rise in eastern France due to heat

High levels of ragweed (ambroisie) pollen are impacting eastern and central-eastern France, with allergy risks reaching a level 4 out of 5 in the Auvergne-Rhône-Alpes and Bourgogne-Franche-Comté regions. Subtropical air masses and high temperatures, reaching up to 30°C in some areas, are facilitating the dispersion of pollen, particularly south of the Loire.

While ragweed remains a primary concern in the Rhône Valley and Massif Central, nettles (urticacées) are also showing significant concentrations in Normandy, Île-de-France, and Bourgogne-Franche-Comté. In the north and north-east, expected rainfall may temporarily lower pollen concentrations by washing the atmosphere.

Health authorities note that climate change—characterized by milder winters and prolonged summers—is allowing ragweed to develop earlier and spread to more zones. Exposure can lead to chronic respiratory inflammation, increased sensitivity to pollutants, and the development of chronic asthma.