The occurrence of Ambrosia pollen in Rzeszów, Kraków and Poznan, Poland: investigation of trends and possible transport of Ambrosia pollen from Ukraine.

Previous studies have shown that ragweed pollen arrives in Poland from sources in the south, in Slovakia, the Czech Republic, Hungary and Austria. It is likely that ragweed pollen also arrives from sources in the southeast (e.g. Ukraine). This hypothesis was investigated using 13 years of pollen data and back-trajectory analysis. Ambrosia pollen data were collected at three sites in Poland, Rzeszów, Kraków and Poznan. The amount of ragweed pollen recorded at Rzeszów was significantly higher than in Poznan and Kraków. This can be related to either a higher abundance of local populations of Ambrosia in south-east Poland or the proximity of Rzeszów to foreign sources of ragweed pollen. The combined results of pollen measurements and air mass trajectory calculations identified plumes of Ambrosia pollen that were recorded at Rzeszów, Kraków and Poznan on 4 and 5 September 1999 and 3 September 2002. These plumes arrived at the pollen-monitoring sites from an easterly direction, indicating sources of Ambrosia pollen in eastern Poland or Ukraine. This identifies Ukraine as a possible new source of ragweed pollen for Poland and therefore an important source area of Ambrosia pollen on the European Continent.

Regional importance of Alnus pollen as an aeroallergen: a comparative study of Alnus pollen counts from Worcester (UK) and Poznan (Poland).

Daily average Alnus pollen counts (1996-2005) from Worcester (UK) and Poznan (Poland) were examined with the aim of assessing the regional importance of Alnus pollen as an aeroallergen. The average number of Alnus pollen grains recorded annually at Poznan was more than 2.5 times that of Worcester. Furthermore, daily average Alnus pollen counts exceeded the thresholds of 100, 500 and 1,000 grains/m3 more times at Poznan than Worcester. Skin prick test results (1996-2005) and allergen-specific IgE (asIgE) measurements using the CAP (Pharmacia) system (2002-2005), were supplied by the Allergic Diseases Diagnostic Centre in Poznan. The annual number of positive skin prick tests to Alnus pollen allergens was significantly related (p<0.05) to seasonal variations in the magnitude of the Alnus pollen catch recorded at Poznan (r=0.70). The symptoms of patients with positive skin prick tests to Alnus pollen allergens were: 51% pollinosis, 43% atopic dermatitis, 4% asthma, 1% chronic urticaria and 1% eczema. On a scale of 0-6, 20.5% of patients examined for serum asIgE in relation to Alnus pollen allergens had asIgE measurements in classes 5 and 6. Alnus pollen is generally considered to be mildly allergenic. However, the amount of Alnus pollen released into the atmosphere in places such as Poznan may increase its impact on the population and make it one of the more important aeroallergens present.

Factors involved in the phenological mechanism of Alnus flowering in Central Europe.

The objectives of this paper are to ascertain the main factors involved in the phenological mechanism of alder flowering in Central Europe by understanding the influence of the main meteorological parameters, the North Atlantic Oscillation (NAO) effect and the study of the Chill and Heat requirements to overcome dormancy. Airborne pollen (1995-2007) was collected in Poznan (Poland) by means a volumetric spore trap. Temperatures for February, and January and February averages of the NAO are generally key factors affecting the timing of the alder pollen seasons. Chilling accumulation (which started in Poznan at the beginning of November, while the end took place during the month of January) of 985 CH with a threshold temperature of -0.25 degrees C, followed by 118 GDD degrees C with a threshold temperature of 0.5 degrees C, were necessary to overcome dormancy and produce the onset of flowering. The calculated dormancy requirements, mean temperatures of the four decades of the year, and January and February average NAO index recorded during the period before flowering, were used to construct linear and multiple regression models in order to forecast the start date of the alder pollen seasons Its accuracy was tested using data from 2007, and the difference between the predicted and observed dates ranged from 3-7 days.