Comparative Effects of Dissolved copper and Copper Oxide nanoparticles on sea Anemone Aiptasia Pallida

The environmental implications of increased NP use are largely unknown, particularly in marine systems. This research investigated effects of copper oxide (CuO) NP on the sea anemone, Aiptasia pallida, exposed to four concentrations (0, 10, 50, and 100 µg/l) for 21 days. Sea anemones were collected and measured for tissue metal accumulation as well as activity of the enzymes: catalase, glutathione peroxidase, glutathione reductase, and carbonic anhydrase. CuO NP were observed for size and shape using scanning electron microscope and the presence of metal was confirmed by using EDS Oxford. A. pallida accumulated copper in their tissues in a concentration and time dependent manner over the 21 d exposure period. As a consequence of increased CuO NP exposure concentrations, the anemones increased the activities of all of the enzymes measured.  Additionally, enzyme activities remained significantly elevated in the highest two treatments (50 and 100 µg/L), even after 21 days of exposure, indicative of stress in these organisms.  This finding differs from past studies in our laboratory with dissolved copper, where recovery of these anti-oxidant enzymes to control levels was reported. This study is useful in discerning differences between CuO and dissolved copper exposure to aquatic organisms.