Biomonitring of drainage water quality by eichhornia crassipes (Mart.) solms in Bahr El-Baqar Drain, Egypt

Abstract

Background and Objective: Egypt is considered as an arid country and drainage water reuse is used on a broad range. The government is seeking to develop a monitoring program aiming at evaluating the drainage water quality. Methodology: Biomonitoring is considered as most accurate tool in the assessment of water quality and most expressive for the status of the environment. Bahr El-Baqar drain from the most polluted drains in Egypt. Results: Results showed a pronounced spatial variation in metal concentrations along Bahr El-Baqar drain gradient in sequences of Ni>Pb>Co>Fe>Zn>Mn>Cu>Cd. The mean values of Zn, Fe, Mn, Cu, Cd, Co, Ni and Pb concentrations in water were relatively high in downstream section compared to the other sections of the drain as follow, 0.45, 0.6, 0.22, 0.2, 0.06, 0.66, 2.61 and 0.80 ppm, respectively. Meanwhile, the lowest mean values of these metals were observed at upstream section of drain (0.15, 0.33, 0.09, 0.07, 0.03, 1.14 and 0.34 ppm, respectively) while the lowest mean values for Co (0.45 ppm) observed at the middle section of drain. According to Food and Agriculture Organization, Cd, Co and Ni mean concentration were out permissible levels at all drain sections. The heavy metals concentrations were higher in plant root than that found in the plant shoot. The Ni concentrations in E. crassipes was within critical ranges at all drain sections while, Mn was critical ranges at middle and downstream sections. Bioaccumulation factor (BAF) values of the metals showed spatial variation and the plant root exhibited higher BAF than the plant shoot. Conclusion: In conclusion, the results indicated the ability of the E. crassipes to absorb and accumulate high level of heavy metals which qualified the plant to be a good biomonitor for drainage water quality. In addition, using this aquatic plant is succeeded in biomintoring process and reflect the heavy metals status in the drain.