AQUATIC PLANTS AS A POSSIBLE WAY FOR PSYCHOACTIVE PHARMACEUTICALS AND DRUGS REMOVAL FROM WASTEWATER

摘要

In this study, we analyzed 30 selected psychoactive drugs and metabolites in two WWTPs in Slovak republic. Consequently, we were interested in a possibility of alternative tertiary post-treatment of effluent water with aquatic plants. Our results indicate that compounds such as THC-COOH, benzoylecgonine, cocaine and amphetamine are considerably degraded in the mechanical and biological stage of WWTP. Both examined WWTPs are not able to effectively eliminate compounds like tramadol, oxazepam or venlafaxine (removal efficiency is about 30%). WWTPs influent was pretreated in batch tests with aquatic plants. Significant cleaning efficiency was observed after treatment with Iris pseudacorus, Pistia stratiotes, Limnophila sessiliflora and Cabomba caroliniana. All aquatic plants except Pistia stratiotes were able to eliminate most of the analyzed compounds with more than 50% effectiveness. Consequently, we have analyzed different parts of plants. The plant Pistia stratiotes contained in the leaves methamphetamine in concentration of 3666 ng/g, Cabomba caroliniana (289 ng/g) and Limnophila sessiliflora (1242 ng/g). In a leaf from Cabomba caroliniana, tramadol and venlafaxine were also identified (1128 a 367 ng/g). In addition to laboratory tests, we have also analyzed aquatic plant Lemna minor growing directly at the effluent of two WWTPs after a period of three months. Analyses of leaves of this plant, however, did not confirm the occurrence of the studied compounds.