ATMOSPHERIC TRANSPORTATION OF MARIJUANA POLLEN FROM NORTH-AFRICA TO THE SOUTHWEST OF EUROPE

As a result of aerobiological samples taken on the Costa del Sol (S. S pain), Cannabis sativa L. (marihuana) pollen was detected from May to September 1991-1996, always sporadically and usually during the aftern oons. Sampling was by two volumetric spore traps set up in Malaga and Estepona, two coastal towns approximately 90 km apart. A study of the days when this pollen was recorded points to the movement of air masse s from North Africa to southern Spain. Furthermore, the isentropic air trajectories calculated for these days reinforce the possibility of t he pollen originating in marihuana plantations in northern Morocco (Ri f). This study demonstrates the application of aerobiology to the cont rol of the source, quantity and phenology of the crop. (C) 1997 Elsevi er Science Ltd.