STUDY OF TOXICITY AND BIOACCUMULATION OF DIFFERENTS CD AND PB CONCENTRATION IN ULOTHRIX CYLINDRICUM

The green alga Ulothrix cylindricum was cultured under different concentrations of Cd (0.5, 1,2 and 4 mg/l) and Pb (5, 10, 20 and 40 mg/l). Growth rate of alga was slightly decreased at low concentration and inhibited by high suited metals concentration, Cd was acutely toxic to alga at all concentrations and it was more toxic than Pb in low concentration. Flame atomic absorption spectrophotometer was used to determine the accumulated metals in the alga. The accumulation of Cd and Pb has increased with increased of the exposure period. The inhibition averages were increased with the increase of the metal concentration as well as elongating the exposure period.