Toxicological response of the green alga Scenedesmus bijuga to mercury and lead.

Effect of mercury or lead on the growth, bioaccumulation and some enzyme activities of one of the most common algae in River Nile, Scenedesmus bijuga, was determined. The cell count and chlorophyll a content decreased with an increase in mercury or lead concentrations in a culture medium, particularly at higher doses. Higher mercury and lead uptake was observed with increasing concentration of the elements. The alga accumulated appreciably more mercury than lead. At higher doses, the two elements strongly suppressed some enzyme activities of primary S. bijuga metabolism.