Experimental investigation of plants interactions with airborne pollutants in an atmospheric simulation chamber

As urban areas continue to grow, the need for effective pollution mitigation strategies becomes more critical. This study presents the outcomes of a set of experiments conducted in an atmospheric simulation chamber (ChAMBRe: Chamber for Aerosol Modelling and Bioaerosol Research) to evaluate the uptake of NO₂ and PM main components (black carbon and dust) capacity of 3 different plant species: Myrtus communis, Nerium oleander and Taxus baccata. To isolate the interactions between plants and individual pollutants, each pollutant was sequentially injected into ChAMBRe one at a time. Finally, to simulate real-world conditions, a mixture of all pollutants was injected. The concentration of pollutants within the chamber was monitored in real-time thanks to the ChAMBRe slow control and data logging system. Results indicate different removal capacities of the selected species and varying relationships between plants and pollutants, suggesting different potential applications in urban pollution mitigation strategies. Among the tested species, T. baccata demonstrated the most consistent and well-balanced performance across all pollutants, with notably high effectiveness in capturing black carbon. M. communis exhibited the highest specialization in the uptake of black carbon, although its performance declined significantly in the dust exposure scenarios. In contrast, N. oleander showed the highest capacity for capturing dust particles, while being less effective in the presence of the other pollutants. This study provides new insights into the ability of plants, especially M. communis, to act as natural biofilters and lays the groundwork for future applications in environmental and urban planning.