Seasonal variations of allergenic pollen in a Mediterranean region - Alexandroupolis, north-east Greece

Abstract

Objectives. The aim of this study was to describe the aerobiological characteristics of NE Greece, identify the most prevalent taxa, define the duration of the main pollen season and correlate allergen records with meteorological parameters. Materials and method. A 7-day volumetric trap, running continuously throughout the year, was used to collect circulating pollen. Pollen taxa were characterized by standard protocols and counted as grains/m3. The main pollen season was deduced from these data and running means (10-day averages) were plotted against time. Correlations with climatic factors (temperature, rain, humidity, wind velocity) were assessed by single linear regression analysis. Results. In total, 11 pollen families were identified, including 6 arboreal and 5 non-arboreal taxa. The 5 most prevalent taxa were Oleaceae, Fagaceae, Poaceae, Cupressaceae and Pinaceae. Peak pollen concentrations were detected in April and May, with daily averages exceeding 410 grains/m3. Compositeae had the longest pollen season of 135 days and Oleaceae the shortest, extending to only 27 days. Correlations with meteorological parameters showed variable associations among different taxa, with mean temperature (p<0.001), relative humidity (p=0.015), and wind speed (p=0.042) emerging as the most significant determinants as regards total pollen counts. Conclusions. Describing the aerobiological characteristics of NE Greece enabled the identification of allergenic risks that are specific for this region. Records generated in this study can be used to alert sensitized individuals of prevailing seasonal patterns, in order to take necessary precautions against imminent exposures. The monitoring system established here can serve as a reference guide for future epidemiological research focusing on allergic asthma and rhinitis.