Developmental effects of two different copper oxide nanomaterials in sea urchin (Lytechinus pictus) embryos

• Main Authors: Torres-Duarte, Cristina, Adeleye, Adeyemi S, Pokhrel, Suman, Mädler, Lutz, Keller, Arturo A, Cherr, Gary N
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: eScholarship, University of California 2016
• Subjects: Life Below Water; Animals; Copper; Copper Sulfate; Embryo; Nonmammalian; Embryonic Development; Lytechinus; Nanostructures; Particle Size; Surface Properties; Embryonic axis disruption; nanoparticle dissolution; oxidative stress; sea urchin embryo development; Biomedical Engineering; Nanotechnology; Toxicology; White Sea
• Online Access: https://escholarship.org/uc/item/4v5833d4

Copper oxide nanomaterials (nano-CuOs) are widely used and can be inadvertently introduced into estuarine and marine environments. We analyzed the effects of different nano-CuOs (a synthesized and a less-pure commercial form), as well as ionic copper (CuSO4) on embryo development in the white sea urchin, a well-known marine model. After 96 h of development with both nano-CuO exposures, we did not detect significant oxidative damage to proteins but did detect decreases in total antioxidant capacity. We show that the physicochemical characteristics of the two nano-CuOs play an essential role in their toxicities. Both nano-CuOs were internalized by embryos and their differential dissolution was the most important toxicological parameter. The synthesized nano-CuO showed greater toxicity (EC50 = 450 ppb of copper) and had increased dissolution (2.5% by weight over 96 h) as compared with the less-pure commercial nano-CuO (EC50 = 5395 ppb of copper, 0.73% dissolution by weight over 96 h). Copper caused specific developmental abnormalities in sea urchin embryos including disruption of the aboral-oral axis as a result in changes to the redox environment caused by dissolution of internalized nano-CuO. Abnormal skeleton formation also occurred.