Alder pollen season in northern Poland in 2017

Tree pollens are responsible for type I allergies during the flowering season in late winter and early spring. Pollen grains from e.g. alder constitute the important allergen sources in this respect in the northern hemisphere. The aim of the study was to investigate the concentration of alder (Alnus spp.) in Szczecin, Drawsko Pomorskie, Bydgoszcz, Olsztyn, Warsaw and Bialystok in 2017. In northern Poland, the genus Alnus Mill. is represented by only 2 species, A. glutinosa (L.) Gaertner and A. incana (L.) Moench. Measurements were performed by the volumetric method (Burkard and Lanzoni pollen samplers). Pollen season was defined as the period in which 98% of the annual total catch occurred. Seasonal Pollen Index (SPI) was estimated as the annual sum of daily average pollen concentrations. The pollen season of alder started first in Szczecin, on the 21st February and also in Bialystok and Drawsko Pomorskie on the 22nd February (only one day later). This pollen season lasted till the 3rd April in Bialystok. The differences of pollen seasons duration ware not considerables. The highest, record airborne concentration of 1215 pollen grains/m3 was noted in Szczecin on the 4th March and in Warsaw, Drawsko Pomorskie, Bydgoszcz and Olsztyn on the 5th of March. The peak values of seasonal pollen count occurred between 4th and 22nd March in all cities.