The influence of Lemna sp. and Spirogyra sp. on the removal of pharmaceuticals and endocrine disruptors in treated wastewaters

Abstract

The presence of pharmaceuticals and endocrine-disrupting chemicals (EDCs) in wastewater treatment plant effluents is an issue of great concern due to the negative effects that these compounds may have on human health and ecosystems. The present study aims to assess the capacity of two aquatic plants (Lemna sp. and Spirogyra sp.), commonly found in polishing ponds, for removing six pharmaceutical compounds (diclofenac, acetaminophen, ibuprofen, carbamazepine, clofibric acid, and propranolol), two EDCs (17α-ethinylestradiol and bisphenol A), and one stimulant (caffeine) under laboratory-scale conditions. Planted and unplanted reactors fed with secondary-treated wastewater or ultrapure water in both covered and uncovered conditions were studied. The highest removal efficiencies, which ranged from 31 to 100 %, were achieved in uncovered planted systems containing secondary-treated wastewater after 20 days of incubation. The results demonstrated that non-charged compounds with a log Kow between 2 and 4 were affected by the presence of vegetation, probably due to their plant uptake, whereas negatively charged compounds were not. This highlights that the presence of plants in polishing ponds plays an important role in the removal of pharmaceuticals and EDCs