Quantitative trends in annual totals of five common airborne pollen types (<i>Betula</i>, <i>Quercus</i>, Poaceae, <i>Urtica</i>, and <i>Artemisia</i>), at five pollen-monitoring stations in western Europe
Aerobiologia, 19 (3):
171--184 (Sep 1, 2003)DOI: 10.1023/b:aero.0000006528.37447.15
Abstract
The existence of long-term (20–33 years) trendsin the annual totals of daily airborne pollenconcentrations of five common and/or allergenicwind pollinating taxa was evaluated at fivepollen-monitoring stations in western Europe:Delmenhorst (D), Helmond (NL), Brussels (B),Leiden (NL), and Derby (UK). At all stations,identical or comparable volumetric traps wereused to sample pollen from the air. For grasspollen no increasing or decreasing trends werefound at any station. Trends for birch pollenand oak pollen are increasing, but notsignificant at the stations with the higherannual totals (Delmenhorst and Helmond),probably due to strong year-to-yearfluctuations. At all five stations significantincreasing trends for stinging nettle pollenwere observed. Trends for mugwort pollen aresignificant at all stations, but in differentdirections. Longer periods of observations areneeded to arrive to more definitive conclusionsabout trends in airborne pollenconcentrations.