title: Phytoremediation of imazalil and tebuconazole by four emergent wetland plant species in hydroponic medium.
abstract: Pollution from pesticide residues in aquatic environments is of increasing concern. Imazalil and tebuconazole, two commonly used systemic pesticides, are water contaminants that can be removed by constructed wetlands. However, the phytoremediation capability of emergent wetland plants for imazalil and tebuconazole, especially the removal mechanisms involved, is poorly understood. This study compared the removal of both pesticides by four commonly used wetland plants, Typha latifolia, Phragmites australis, Iris pseudacorus and Juncus effusus, and aimed to understand the removal mechanisms involved. The plants were individually exposed to an initial concentration of 10 mg/L in hydroponic solution. At the end of the 24-day study period, the tebuconazole removal efficiencies were relatively lower (25%-41%) than those for imazalil (46%-96%) for all plant species studied. The removal of imazalil and tebuconazole fit a first-order kinetics model, with the exception of tebuconazole removal in solutions with I. pseudacorus. Changes in the enantiomeric fraction for imazalil and tebuconazole were detected in plant tissue but not in the hydroponic solutions; thus, the translocation and degradation processes were enantioselective in the plants. At the end of the study period, the accumulation of imazalil and tebuconazole in plant tissue was relatively low and constituted 2.8-14.4% of the total spiked pesticide in each vessel. Therefore, the studied plants were able to not only take up the pesticides but also metabolise them.
authors: Department of Bioscience, Aarhus University, 8000 Aarhus C, Denmark. Electronic address: lvtao@bios.au.dk.
authors: Tao
authors: T
authors: Lv
authors: Department of Bioscience, Aarhus University, 8000 Aarhus C, Denmark; College of Life Science, South China Normal University, Guangzhou 510631, PR China. Electronic address: yzhang@bios.au.dk.
authors: Yang
authors: Y
authors: Zhang
authors: Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark. Electronic address: moes@envs.au.dk.
authors: Mònica E
authors: ME
authors: Casas
authors: Department of Bioscience, Aarhus University, 8000 Aarhus C, Denmark. Electronic address: pedro.carvalho@bios.au.dk.
authors: Pedro N
authors: PN
authors: Carvalho
authors: Department of Bioscience, Aarhus University, 8000 Aarhus C, Denmark. Electronic address: carlos.arias@bios.au.dk.
authors: Carlos A
authors: CA
authors: Arias
authors: Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark. Electronic address: kb@envs.au.dk.
authors: Kai
authors: K
authors: Bester
authors: Department of Bioscience, Aarhus University, 8000 Aarhus C, Denmark. Electronic address: hans.brix@bios.au.dk.
authors: Hans
authors: H
authors: Brix
mesh_terms: D001673:Biodegradation, Environmental; D005659:Fungicides, Industrial / Q000378:metabolism*; D018527:Hydroponics; D007093:Imidazoles / Q000378:metabolism*; D019684:Magnoliopsida / Q000378:metabolism*; D014230:Triazoles / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000378:metabolism*; D053833:Wetlands
chemical_list: D005659:Fungicides, Industrial; D007093:Imidazoles; D014230:Triazoles; D014874:Water Pollutants, Chemical; C087114:tebuconazole; C017435:enilconazole
keywords: Aquatic macrophytes; Constructed wetland; Ecotechnology; Fungicide; Pesticide; Phytotoxicity