A one year survey of airborne pollen and spores in the neotropical city of Bogota (Colombia)

Abstract

A one-year study of potentially allergenic airborne biological particles was carried out in Bogotá, the capital city of Colombia. Bogotá is a populous city of approximately 6 million inhabitants. Located at 4 degrees Lat N and 2,600 m on the sea level, it has a mild tropical climate. The mean annual temperature of the city is 14 degrees C, the annual rainfall 1,013 mm and the relative humidity 72%. During the year June '86-May '87 the pollen count was 7,626 contributed by 72 grain types. Among these, 24 taxa have been identified. The majority of the grains came from imported trees; Cupressus spp was the main contributor. Weed pollen counts, which include the Compositae (ragweed), were notoriously low (4% of the total). The spore count was 13,264, almost twice as large as that of pollen. Fourty-four spore taxa were identified out of 72 types recorded. More than two-thirds (72%) of the spore count was contributed by the deuteromycetes. Cladosporium was the more frequently recorded genus, Penicillium/Aspergillus second next. Miscellaneous particles recorded were 609 Algae and 142 fern spores. Because of its location in the tropics, Bogotá has neither true seasons nor the large variations in atmospheric particle counting which are typical of temperate zones. However, distinct periodical increments in the counts of various species (peaks) may be the cause of seasonal allergic symptoms.