Abstract

Phytoremediation is a relatively new approach to treat wastewater contaminated by organic and inorganic substances including heavy metals. The effectiveness of two aquatic plants, Centella asiatica and Eichhornia crassipes, were evaluated for their capabilities in removing copper from copper solution. The aim of this study is to determine the potential of these aquatic plants to act as hyperaccumulators. The aquatic plants were put in 8 liters of solution containing 1.5 mg/L, 2.5 mg/L and 5.5 mg/L of copper, for a period of 21 days. Analyses of heavy metals contents were conducted using an Atomic Adsorption Spectrometer. Results showed an increase of copper within the plants’ roots and shoots tissues and a decrease of copper concentration in the solution. The maximum removal of copper in the solutions containing Centella asiatica was 99.6 % as compared to 97.3 % in solutions containing Eichhornia crassipes. Centella asiatica accumulated a maximum amount of copper of 1353.0 mg/kg whereas Eichhornia crassipes accumulated 1147.5 mg/kg of copper in their roots. The accumulation of copper of more than 1000 mg/L in plant tissues indicate that both aquatic plants can be considered as hyperaccumulators of copper. Roots tend to accumulate a higher amount of copper than shoots due to translocation process. Significant removal of copper were obtained at p<0.01 for containers containing both aquatic plants, indicating that Centella asiatica and Eichhornia crassipes can be utilized in the phytoremediation method to remove copper from wastewater.