Pollen season identification for three pollen taxa in Thessaloniki, Greece: a 30-year retrospective analysis

Abstract

To examine the applicability of the recently proposed criteria by the European Academy of Allergy and Clinical Immunology (EAACI) for pollen season (PS) definition, we applied them to a 30-year time series of daily concentrations of cypress (Cupressaceae), olive (Oleaceae), and grass (Poaceae) airborne pollen from a Mediterranean city, Thessaloniki, Greece. These criteria led to PS definition for every year in the case of grasses, but they did not result to a defined pollen season in each year for 10% of the examined period in the case of cypress (Cupressaceae) and even for 60% in the case of olive (Oleaceae). Application of the EAACI thresholds to data series of Thessaloniki shows the need for an accurate analysis and revision of the symptom thresholds for PS definition for olive and cypress in the Mediterranean area. Given that the PS, as defined after the EAACI criteria, corresponds to only the part of the PS inducing allergy symptoms, a different term ‘allergy symptom-inducing pollen season’ is proposed so as to avoid confusion but also make clear that, depending on the purpose of the study, different criteria may be used for PS definition.