Potential of an estuarine salt marsh plant (Phragmites australis (Cav.) Trin. Ex Steud10751) for phytoremediation of bezafibrate and paroxetine

This study aimed to evaluate the potential of a salt marsh plant and its rhizosphere microorganisms for the removal of two pharmaceutical compounds, bezafibrate and paroxetine, from estuarine environment. Plants were exposed for 7 days to a simplified estuarine medium, elutriate solution with or without sediment, doped with bezafibrate or paroxetine. Tests were done in absence and presence of nutrients or copper. Phragmites australis (Cav.) Trin. Ex Steud, alone or with the sediment microbial communities, contributed for pharmaceuticals removal. In the presence of P. australis, for paroxetine a 65% removal was observed. Removal increased up to 90% when sediment was present. For bezafibrate, removals reached ca. 47% in P. australis presence, increasing to ca. 70% when nutrients were added to the medium, indicating a good nutritional state can contribute for a higher compound removal. When Cu was added, 75% removal for bezafibrate and 95% removal for paroxetine were observed indicating the metal might influence the removal of the pharmaceuticals. Overall, the plant and its rhizosediments and associated microorganisms showed potential for pharmaceuticals removal from estuaries, eventually degrading the selected compounds, a feature requiring more research. Results indicate that phytoremediation could be a viable option for eliminating/diminishing the environmental impact of pharmaceutical compounds in estuarine areas.