Potential Use of Lemna Minor for the Phytoremediation of Isoproturon and Glyphosate

Abstract

Pesticides are being detected in water bodies on an increasingly frequent basis. The present study focused on toxicity and phytoremediation potential of aquatic plants to remove phytosanitary products from contaminated water. We investigated the capacity of Lemna minor (L. minor) to eliminate two herbicides isoproturon and glyphosate from their medium. Since phytoremediation relies on healthy plants, pesticide toxicity was evaluated by exposing plants to 5 concentrations (0–20 μg L⁻¹ for isoproturon and 0–120 μg L⁻¹ for glyphosate) in culture media for 4 d using growth rate and chlorophyll a fluorescence as endpoints. At exposure concentrations of 10 μg.L⁻¹ for isoproturon and 80 μg.L⁻¹ for glyphosate, effects on growth rate and chlorophyll fluorescence were minor (< 25%), so that this initial concentration was selected to study herbicide removal. After a 4-d incubation, removal yields were 25% and 8% for isoproturon and glyphosate, respectively.

KEY WORDS:

• pesticides
• chlorophyll fluorescence
• uptake
• duckweed
• herbicide
• xenobiotic

ACKNOWLEDGMENTS

This work is a part of the “Contrat d'objectifs AQUAL” and is funded by the city of Reims and the Agence de l'Eau Seine-Normandie. The authors are grateful to Pr. E. Guillon (ICMR-GCC, University of Reims) for the HPLC equipment.