Annual, daily and diurnal variations in pollen from Olea europaea L. in the atmosphere of Granada (Spain).

The allergenic capacity of Olea europaea L. pollen is very important in several cities of the southern Iberian Peninsula, producing most pollinoses diagnosed in these cities. We have carried out a study on the annual, daily and diurnal variations in pollen from O. europaea in the atmosphere of Granada (Spain) during 4 consecutive years. Samplings were carried out with the aid of a Burkard spore trap. Very low levels of Olea pollen grains were first detected in the atmosphere from the end of April. Pollen levels peaked in May and June, and started to decrease from the last days of June and in July. Pollen in the atmosphere is related to meteorological parameters: temperature has a positive influence on pollinization and rainfall produces a negative effect. The diurnal variation pattern of pollen grain concentrations was quite homogeneous throughout the study, featuring an important increase around midday and a moderate decrease in the first hours of the morning and in the late evening.