Influence of Heavy Metals on the Growth of Chlorella vulgaris
Growth inhibition of chromium (Cr), cadmium (Cd) and lead (Pb) to fresh water microalga Chlorella vulgaris (C. vulgaris) FACHB-8 was examined. These results demonstrated that the concentration level (EC50 value) of three heavy metals (Cr, Cd and Pb) could be utilized as an indicator for evaluating the toxicities of Cr, Cd and Pb for microalga growth. The EC50 values of Cr for C. vulgaris were 0.22, 0.07 and 0.04 mg/L at 24, 48 and 72 h based on Algorithm 2 (%Ir, percent inhibition in average specific growth rate), respectively. The EC50 values of Cd for C. vulgaris were 2.76, 1.08 and 0.93 mg/L at 24, 48 and 72 h based on Algorithm 2, respectively. The EC50 values of Pb for C. vulgaris were 73.21, 65.02 and 48.38 mg/L at 24, 48 and 72 h based on Algorithm 2, respectively. The results laid a good foundation for the application of C. vulgaris in the water quality monitoring.