Links between recent trends in airborne pollen concentration, meteorological parameters and air pollutants

Biogenic aerosols may play an active role in various diseases. Pollutant gases and bioaerosols coexist in the atmosphere with the possibility of interacting with each other increasing their adverse impacts on human health. The study of long-term trends and the correlation between the pollen concentration from selected taxa (especially those related to allergies) and both the main atmospheric pollutants and the meteorological parameters has enabled us to identify the main factors that affect pollen concentration in the atmosphere. This study analyzes the long-term trend in CO, NO, NO2, PM10, SO2 and O3 from 1997 to 2016 and Fraxinus, Poaceae and Populus pollen concentrations in the city of León from 1994 to 2016. In general, there is a significant decreasing trend in atmospheric pollutant concentrations and a significant increasing trend in Fraxinus pollen concentrations. In addition, the influence of air pollutants and climatic factors on pollen concentrations and pollination period duration was studied using the Spearman correlation, showing that the flowering and pollination periods depend largely of the weather conditions before these periods and are influenced by air pollutant concentrations.