Cerium oxide nanoparticles induce oxidative stress in the sediment-dwelling amphipod Corophium volutator

• Published in: Nanotoxicology 2016-04, Vol.10 (4), p.480-487
• Main Authors: Dogra, Yuktee, Arkill, Kenton P., Elgy, Christine, Stolpe, Bjorn, Lead, Jamie, Valsami-Jones, Eugenia, Tyler, Charles R., Galloway, Tamara S.
• Format: Article
• Language: English
• Subjects: Amphipoda - drug effects; Amphipoda - metabolism; Animals; Biological Availability; Cerium - chemistry; Cerium - pharmacokinetics; Cerium - toxicity; Cerium oxide; Corophium volutator; DNA Breaks - drug effects; Geologic Sediments; Lipid Peroxidation - drug effects; Nanoparticles - chemistry; Nanoparticles - metabolism; Nanoparticles - toxicity; nanotoxicology; oxidative stress; Oxidative Stress - drug effects; Spectroscopy, Electron Energy-Loss; Superoxide Dismutase - metabolism
• ISSN: 1743-5390; 1743-5404
• DOI: 10.3109/17435390.2015.1088587

Cerium oxide nanoparticles (CeO 2 NPs) exhibit fast valence exchange between Ce(IV) and Ce(III) associated with oxygen storage and both pro and antioxidant activities have been reported in laboratory models. The reactivity of CeO 2 NPs once they are released into the aquatic environment is virtually unknown, but this is important to determine for assessing their environmental risk. Here, we show that amphipods (Corophium volutator) grown in marine sediments containing CeO 2 NPs showed a significant increase in oxidative damage compared to those grown in sediments without NPs and those containing large-sized (bulk) CeO 2 particles. There was no exposure effect on survival, but significant increases in single-strand DNA breaks, lipid peroxidation and superoxide dismutase activity were observed after a 10-day exposure to 12.5 mg L −1 CeO 2 . Characterisation of the CeO 2 NPs dispersed in deionised or saline exposure waters revealed that more radicals were produced by CeO 2 NPs compared with bulk CeO 2 . Electron energy loss spectroscopy (EELS) analysis revealed that both CeO 2 NPs were predominantly Ce(III) in saline waters compared to deionised waters where they were predominantly Ce(IV). In both types of medium, the bulk CeO 2 consisted mainly of Ce(IV). These results support a model whereby redox cycling of CeO 2 NPs between Ce(III) and Ce(IV) is enhanced in saline waters, leading to sublethal oxidative damage to tissues in our test organism.