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Genotoxicity of copper oxide nanoparticles in the mussel Mytilus trossulus
Valentina V. Slobodskova, Sergey P. Kukla1,2 and Viktor P. Chelomin1,2
1
Laboratory of Marine Toxicology, Pacific Oceanological institute (POI), Far-Eastern Branch of Russian Academy
of Science (FEB RAS), Vladivostok, Russia. E-mail: [email protected]
2
Department of Ecology, Far Eastern Federal University (FEFU), Vladivostok, Russia
Copper oxide (CuO) is one of the most widely used nanoparticle applications in consumer products. They are
extensively used in microelectronics, cosmetics and catalysts. In the present study, the DNA damaging potential of
CuO-NPs in the marine eastern mussel Mytilus trossulus was evaluated and compared to dissolved copper exposures.
Genotoxicity was assessed by the single cell gel electrophoresis (comet) assay in mussel gill and digestive gland cells.
Mussels were exposed to CuO-NPs for 7 days at 0.020 mg/L nominal concentration level. Mussel tissues (digestive
glands and gills) were rapidly dissected after the exposure to determine DNA damage by the Comet assay. The Comet
assay was used to measure endogenous DNA damage in gill and digestive gland cells from unexposed and exposed
mussels. Exposure to the CuO-NPs resulted in a significant increase in DNA damage in the gill cells of M. trossulus.
The distribution of cells clearly demonstrated that after exposure to CuO-NPs, the majority of cells showed more DNA
damage than cells from the control mollusks. The present data demonstrate that CuO-NPs induce genotoxic effects in
the marine bivalve mollusk M. trossulus, which may be mediated through oxidative stress. The gill cells showed a
higher degree of DNA damage, demonstrating an increased sensitivity of this tissue to potential genotoxic compounds.