Lead (PB) heavy metal impacts in the green Ulva lactuca (Chlorophyceae) marine algae

Toxicity of different lead (Pb) (0, 2, 4 and 8 mg/L) concentrations in the green Ulva lactuca (Chlorophyta) marine algae at physiological level has been investigated 48 h after Pb treatment under laboratory conditions. Thalus algae damages followed Pb treatment as revealed by microscopy test showed that the 4 and 8 mg/L Pb caused morphological changes in cells viability; whereas, no effect observed at the lowest Pb applied concentration (2 mg/L). Data revealed that Pb stress caused reduction in most investigated physiological parameters i.e. Pigments content, osmotic potential and membrane stability index values. This decline in osmotic potential was significantly ( p ≤ 0.001) different. Whereas, estimated electric conductivity (EC) values increased significantly ( p ≤ 0.001) as applied Pb concentration increased. The current study allowed somewhat to highlight and better understanding Pb impacts in U. lactuca algae. Thereby, the studied algae could be used as a useful bioindicator in Pb polluted ecosystems.