Pollen allergenicity plays an important role on human health and wellness. It is thus of large public interest to increase our knowledge of pollen grain behavior in the atmosphere (source, emission, processes involved during their transport, etc.) at fine temporal and spatial scales. The optical remote sensing group of the Universitat Politècnica de Catalunya performs routinely retrievals of the optical properties of pollen grains once they are airborne. With a consortium of research institutes and universities in Barcelona, the group is involved in a project which goal is twofold: (i) to understand the meteorological conditions favoring the release and dispersion of pollen grains in the atmosphere, and (i) the implementation / validation / evaluation of a pollen module in an online air quality forecast system. In-situ pollen concentrations are made with a Hirst collector, while vertically-resolved pollen optical properties are made with the Barcelona Micro Pulse Lidar (MPL) system.