Abstract: The effects of different concentrations of decabromodiphenyl ether on ultrastucture of sperm in Pacific codGadusmacrocephaluswere studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM).The results showed that there was no significant difference in ultrastructure of sperm between the Pacific cod in the control group and the Pacific cod exposed to 0.5, 5, 50, and 500 ng/L decabromodiphenyl ethers. However, the Pacific cod exposed to 5000 ng/L had the sperm with significant changes in the ultrastructure compared with the fish in the control group. The SEM revealed that white crystalline lesions on the sperm nucleus surface and ruptured nuclei were observed in sperm of the cod exposed to 5000 ng/L for 8 h and 12 h, even though there was no significant change in the ultrastructure of sperm in the Pacific cod exposed for 2 h and 4 h. Under the TEM, no significant change in the sperm morphology was found in the cod exposed to 5000 ng/L for 2 h compared with the fish in the control group. In 5000 ng/L 4 h exposure, however, the expansion of sperm plasma membrane and shifting of mitochondria were observed, and the ruptured plasma membrane, broken, even dissolved, mitochondrial cristae, and vacuolar shallow changes in the matrix were found in the cod exposed to 5000 ng/L for 8 h. The cod exposed to 5000 ng/L for 12 h had deciduous and accumulated flagella in abundance, some disintegrated microtubules and mitochondrial cristae, even disappearance. The findings indicated that the decabromodiphenyl ether led to damages in the plasma membrane, mitochondria and flagella of the sperm, including plasma membrane rupture, mitochondrial-vacuole like change, deciduous and accumulated flagella and disintegrated axoneme microtubules.
2014, Vol. 29 
