Potential of Duckweed (Lemna minor) for Removal of Lead from Wastewater by Phytoremediation

Abstract

This investigation was undertaken to study lead (Pb) uptake by small free floating aquatic plant Lemna minor from wastewater polluted with heavy metals. Metal accumulation process was affected by various parameters such as different pH, temperature and concentration of Pb solution. Total chlorophyll content in Lemna minor was adversely affected which was dependent on Pb concentrations. The plant was adversely affected by pH 6 more than by pH 7 or pH 8. Lead accumulation in the plant tissues increased with increasing Pb concentration. However, the highest removal of Pb was found at pH 9. The highest bioconcentration potential of Pb was observed by Lemna minor (0.900) at pH 6 and the minimum of 0.438 at pH 5. Thus, duckweed may be useful from a phytoremediation standpoint. These results indicate that L. minor has potential for removing Pb from industrial wastewater.