Tributyltin exposure results in craniofacial cartilage defects in rockfish (Sebastiscus marmoratus) embryos.

Tributyltin (TBT) is a ubiquitous marine environmental contaminant, which has been known to cause axial skeletal deformities in fish embryos. However, the effects of TBT on the craniofacial cartilage development of fishes remain unclear. The present study was designed to investigate the effects of waterborne TBT at environmental levels (0, 0.1, 1, and 10 ng L(-1) as Sn) on craniofacial cartilage development in embryos of the rockfish (Sebastiscus marmoratus). Our study showed that TBT exposure induced craniofacial skeletal deformities, such as reduction of the craniofacial skeleton elements and a shorter lower jaw. The expressions of retinoic acid receptor α, sonic hedgehog, and proliferating cell nuclear antigen were depressed and the expressions of vitamin D receptor were increased in the rockfish embryos after TBT exposure. In addition, the activities of Ca(2+)-ATPase were inhibited after TBT exposure. These results suggested that TBT might perturb the proliferation and differentiation of chondrocytes, and disturb calcium homeostasis, thus disorganizing craniofacial skeletal development.