Allergenic airborne grass pollen in Szczecin, Poland.

Department of Botany and Nature Conservation, University of Szczecin, Felczaka3a, 71-412 Szczecin, Poland. mapuc@univ.szczecin.pl
Ann Agric Environ Med 2004;11(2):237–244
Grass pollens are known as very potent aeroallergens. The aim of the studywas to analyse the grass pollen season in Szczecin (western Poland) in the years 2000-2003 and to establisha relationship between the meteorological conditions and the pollen counts of Poaceae. The meteorologicalparameters analysed were the maximum and mean air temperature, relative humidity, amount of precipitationand wind speed. Measurements were performed mainly by the volumetric method. In parallel, gravimetricmonitoring was conducted in 4 Szczecin city districts in order to establish the spatial distributionof pollen in aeroplankton. Pollen seasons were defined as the periods in which 95 % of the total catchoccurred. In the 4 years studied, the lowest concentration of grass pollen was observed in 2000 withthe maximum value of 123 pollen grains in 1 m3 per 24 h. In subsequent seasons, the concentration ofPoaceae pollen increased and the highest concentration of grass pollen, equal to 809 pollen grains in1 m3 per 24 h was noted in 2003. The majority of Poaceae species have constant periods of pollen releaseand the high number of their species means that the pollen season is long and lasts from the beginningof May until the middle of September. The longest pollen season was observed in the year 2000 when thelowest pollen count was found. In sensitive persons the symptoms of pollinosis occur after some thresholdpollen count value, which for grass is 30 grains in 1 m3 per 24 h. Therefore, the greatest threat fromPoaceae pollen allergens is noted from the middle of May and until the end of July, and at the beginningof September. Analysis of the pollen distribution in different Szczecin city districts determined bythe gravimetric method, has shown that the highest exposure to grass pollen allergens occurs in the districtsZelechowa and Sródmieście, in the area with parks, villas and gardens or garden allotments. However,in the pollen season the threshold Poaceae pollen count value is usually exceeded in the entire city.Statistically significant correlations have been found between the grass pollen count in the air andthe maximum wind speed, air temperature, amount of precipitation and relative air humidity. The pollencount of grass is determined by the diversity of local flora and weather conditions, especially by theair temperature and relative humidity.