Influence of copper oxide nanoparticle form and shape on toxicity and bioaccumulation in the deposit feeder, Capitella teleta.

Few in vivo studies have been conducted to assess how nanoparticle (NP) characteristics such as particle form and shape affect their toxicity and bioaccumulation. In the present study, the deposit feeder, Capitella teleta, was used to investigate the influence of copper form (CuO NPs, micron-sized CuO particles, and aqueous Cu) and CuO NP shape (spheres, rods and platelets) on toxicity and bioaccumulation through sediment exposures of approximately 250 μg Cu/g dw sed. There were no effects of nanoparticle form or shape on mortality or growth rate during the exposure period. However, mortality increased to approximately 26.3% on average in all Cu treatments after the depuration period indicating a delayed effect of Cu exposure, despite more than 90% depuration of Cu during this period. A significant effect of nanoparticle shape was detected on body burden, the gross uptake rate constant and the depuration rate constant, suggesting preferential accumulation of rods by the worms. We recommend that additional sublethal endpoints and longer exposure durations should be examined to fully understand the environmental risks of CuO nanoparticles compared to other forms of Cu entering marine sediment systems.