Parental Exposure to CdSe/ZnS QDs Affects Cartilage Development in Rare Minnow ( <i>Gobiocypris Rarus</i>) Offspring

Cartilage development is a sensitive process that is easily disturbed by environmental toxins. In this study, the toxicity of CdSe/ZnS QDs on the skeleton of the next generation (F1) was evaluated using rare minnows (Gobiocypris rarus) as model animals. Four-month-old sexually mature parental rare minnows (F0) were selected and treated with 0, 100, 200, 400 and 800 nmol/L CdSe/ZnS QDs for 4 days. Embryos of F1 generation rare minnows were obtained by artificial insemination. The results showed that with increasing maternal QDs exposure, the body length of F1 embryos decreased, the overall calcium content decreased, and the deformity and mortality rates increased. Alcian blue staining results showed that the lengths of the craniofacial mandible, mandibular arch length, mandibular width, and CH-CH and CH-PQ angles of larvae of rare minnows increased; histological HE staining further indicated that QDs affected the development of chondrocytes. Furthermore, high concentrations of CdSe/ZnS QDs inhibited the expression of the bmp2, bmp4, bmp6, runx2, sox9a, lox1 and col2α1 genes. In conclusion, CdSe/ZnS QDs can affect the skeletal development of F1 generation embryos of rare minnows at both the individual and molecular levels, the damage to the craniofacial bone is more obvious, and the toxic effect of high concentrations of QDs (400 nmol/L and 800 nmol/L) is more significant.