Allergenic pollen in the subdesert areas of the Iberian peninsula

The yearly distribution of Artemisia and Chenopodiaceae-Amaranthaceae, two of the most common types of pollen in a rural area located in the southeast ern part of the Iberian peninsula, was studied over a 3-year period (1995-1 997). The particular bioclimatic conditions of the area, such as its sub-de sert climate, extreme dryness and high mountain location (1,000 m above sea level), have led to the adaptation and abundance of these species in this area. They usually flower in the second half of the year, and are the main pollen types collected in the samples in that time period. The Artemisia po llen levels recorded are the highest in Spain, since there are several spec ies in the area which flower at different times. Chenopodiaceae-Amaranthace ae pollen counts are also very high. The severity of both pollen types was also analyzed. The height of the sampler was taken into account because the quantities at human height can be considerably higher than those recorded at 20 m off the ground. It was concluded that both pollen types should be c onsidered some of the main causes of allergy in this area.