Toxicity of copper, lead, and cadmium on the motility of two marinemicroalgae Isochrysis galbana and Tetraselmis chui

Computer assisted movement tracking was used to characterize the motility of two marine microalgae, Isochrysis galbanaand Tetraselmis chui, and to investigate the toxicity of Cu, Pb, and Cd on motile percentage, curvilinear velocity, average pathvelocity, straight line velocity, linearity, straightness, and wobble. Except for motile percentage, all other motility parameters di eredsignificantly between I. galbana and T. chui. Based on relative motile percentage data, the median e ective concentration (EC50) of Cuon the motility of I. galbana and T. chui was 31.4 and 1.3 mol/L, respectively, while for Pb it was 37.8 and 10.9 mol/L and for Cd itwas 121.6 and 37.8 mol/L, respectively. Compared to I. galbana, T. chui was more sensitive to all tested metals. The toxic e ect of theheavy metals on motility exhibited the following decreasing order for both species: Cu > Pb > Cd. Our results indicate that I. galbanaand T. chui motility is sensitive to heavy metals and can be used as an indicator for toxicology bioassays.