Integrated remediation approach of pharmaceutical wastewater using Pistia stratiotes and its toxicity analysis

In this research, biologically synthesized iron oxide(Fe₂O₃) nanoparticles and phytoremediation studies(Pistia stratiotes) were used to treat the pharmaceutical effluents. This study evaluated the effectiveness of phytoremediation and Fe₂O₃-based adsorption for treating pharmaceutical effluents. The biologically synthesized iron oxide nanoparticle was characterized through UV-DRS, FTIR, and SEM-EDAX. The size of Fe₂O₃ ranged from 400-500nm. Phytoremediation achieved a maximum removal of 85.17% at 200 mg/L, whereas the highest remediation achieved using iron oxide nanoparticles is 60.70% at 400 mg/L. Similarly, a kinetic study revealed that 25 mg of Fe₂O₃ nanoparticles could efficiently degrade different concentrations of mixed phenols at the end of 60 min. Wastewater analysis, such as TDS, Nitrate, DO, and BOD, was performed for 5 days. Chlorophyll a was found to be in the range of 0.002-0.01 mg/g while chlorophyll b was in the range of 0.0-0.036 mg/g. Histopathology studies revealed that mixed phenols had a great effect on the root and leaves of P. stratiotes. The phytotoxicity analysis employing Vigna radiata was performed, revealing that it had the highest tolerance level against mixed phenols, showing germination on 60 mg/L of mixed phenols. Finally, it was inferred that the integrated approach boosted the removal of phenolic compounds from the wastewater.