| Abstract: | Using modified clay is one of the most promising methods for the mitigation of harmful algal blooms（HABs）. However, the environmental impact of modified clay has become a subject of global concern. In this study, turbot（Scophthalmus maximus L.） embryos were used as a model to assess the effect of modified clay on this sensitive stage of fish development. Results show that the 24 and 48 h LC50（median lethal concentrations） of the modified clay were 1.70 and 1.65 g/L, and the safe concentration was 0.47 g/L, which is much higher than the concentration used to treat HAB. The modified clay did not affect significantly the hatchability of turbot embryos but when the concentration exceeded 0.50 g/L, the deformity rate of newly hatched larvae increased significantly. The total length, specific growth rate（SGR）and yolk sac absorption rate of larvae reached their peaks at 0.50 g/L and then gradually decreased as the concentration of modified clay increased. Therefore, a moderate amount of modified clay does not harm the survival and hatching of turbot embryos, or the growth and development of newly hatched larvae. |
