[PERSON] et collaborators have shown that in the Kanto region (Greater Tokyo Area, Japan), the concentrations of ionic species (NO\({}_{3}\)\({}^{-}\), SO\({}_{4}\)\({}^{2-}\), and NH\({}_{4}\)\({}^{+}\)) and gaseous pollutants (NO\({}_{2}\), SO\({}_{2}\), and NH\({}_{3}\)) deposited on pollen grains from _Cryptomeria japonica_ were higher in polluted urban zone than in mountainous areas [12]. In addition, the susceptibility of pollen to pollutants depends on the plant species. [PERSON] et al. showed that the uptake of NO\({}_{2}\) depends on the analyzed pollen and decreases in this order: cypress, timothy grass, and birch [13]. [PERSON] et al. demonstrated that the pollen modifications due to O\({}_{3}\) are species-dependent [14]. On the other hand, the chemical modifications of the elemental composition of pollen grains are not yet well understood. The pollen of anemophilous plants harvested from the anthers contains mainly K, Cl, S, P, Ca, Mg, Fe, Si, Al, Na, and Br [15; 16]. Potassium is the dominant element in freshly collected pollen, but several studies have shown that environmental pollution influences the concentration of this element, which is considered a co-inductor or adjuvant of allergenicity. When the pollen is exposed to a polluted atmosphere, the inorganic elements of the exine are modified so that a predominance of Cl\({}^{-}\) ions, an increased amount of P (_Dactylis glomerata_), and a predominance of or increased S with a slight increase in Cl\({}^{-}\) (_Betula verucosa_) can be observed [15]. Several other elements, such as Zn and Pb, can also be found in pollen, and their relative amounts can change in polluted environments. An increase in Zn concentration was observed for the polluted _Betula_ pollen at various sampling zones in Stockholm [17], and a differential concentration of Pb in _Composite_ pollen was detected according to its presence in zones where the pollen was collected [18]. Nevertheless, the literature data do not allow us to identify an apparent convergence in the modification of the elemental composition of polluted versus unpolluted pollen [19; 20; 21; 22; 23]. Particulate matter (PM) is one of the principal air pollutants and is potentially dangerous to human health. In fact, up to 96% of the European Union's urban population is exposed to fine PM concentrations above World Health Organization guidelines [24]. The assessment of PM concentration and its chemical composition is mainly carried out at monitoring sites in fixed locations, equipped with active air-sampling systems and specific instruments for the continuous measurement of pollutants [25]. Air-quality management typically requires a high number of monitoring stations. Unfortunately, fixed stations have high installation and maintenance costs and have disadvantages such as the need for electricity to operate, the difficulty in finding an appropriate location, and the risk of damage. For all these reasons, the number of monitoring stations, measuring PM, is often insufficient and does not allow for a realistic population risk assessment. Bioindicators can be used as passive samplers alternatively to active sampling stations, to extend PM monitoring networks. Lichens [2; 26] and spider webs [27; 28; 29; 30; 31] have been recently used as passive samplers for air pollution monitoring. Both bioindicators show good properties for collecting PM. However, there are also some drawbacks: lichens are sensitive to temperature, humidity, elevation, and substrate chemistry [32; 33], while for the other bioindicator, the non-contaminated web from laboratory-reared spiders needs to be transplanted to the monitoring site [27; 34]. In this work, olive pollen grains (_Olea europaea_ L.) have been used as a passive particulate matter sampler. To validate the new technique, we exposed pollen samples to air in industrial, urban, and rural areas in Umbria (Central Italy) and quantified the bioaccumulation levels of particulate constituents.