The Bioaccumulation and Toxic Effect of Pyrene andPhenanthrene in Hydrilla verticillata (L.F.) Royal.

A laboratory experiment was conducted to investigate the effect of bioaccumulation levelof Pyrene and Phenanthrene compounds on some physiological parameter of Hydrilla vertcillatafor 10 days. The results were revealed that the bioconcentration factor (BCF) were 2.85 and 0.05which detected under high concentration (200μg/l) while they were 1.85 and 0.03 in the controlgroup for both compounds respectively. The concentrations of two pollutants in the leaves of thetreated plants were ranged (171-2224.2 μg/g. dry weight) and (0.18-9.84 μg/g.dw) for bothrespectively. The results of toxicity showed that increasing of the ion permeability in plasmamembrane (88%) and lipid peroxidation products as malondialdehyde (MDA) were (10.4μmol/lfresh weight) also under high concentration, whereas in control groups decreased to 28% and(1.13μmol/l) for a mixture of compounds. The ascorbic acid, chlorophyll content and lipidpercentage were reduced to 4.8 mg/g.fw, 2.8mg/g and 0.04% in plants leaves while they were18.4mg/g, 0.9mg/g and 0.026% in the control group. The statistical analysis was indicated thatsignificant differences among stressed and control groups in experiment plants.