Ecotoxicity of nanoparticles of CuO and ZnO in natural water.
The acute toxicity of CuO and ZnO nanoparticles in artificial freshwater (AFW) and in natural waters to crustaceans Daphnia magna and Thamnocephalus platyurus and protozoan Tetrahymena thermophila was compared. The L(E)C(50) values of nanoCuO for both crustaceans in natural water ranged from 90 to 224 mg Cu/l and were about 10-fold lower than L(E)C(50) values of bulk CuO. In all test media, the L(E)C(50) values for both bulk and nanoZnO (1.1-16 mg Zn/l) were considerably lower than those of nanoCuO. The natural waters remarkably (up to 140-fold) decreased the toxicity of nanoCuO (but not that of nanoZnO) to crustaceans depending mainly on the concentration of dissolved organic carbon (DOC). The toxicity of both nanoCuO and nanoZnO was mostly due to the solubilised ions as determined by specific metal-sensing bacteria.
Laboratory of Molecular Genetics, National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, Tallinn 12618, Estonia. irina.blinova@kbfi.ee
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Mortimer
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Kahru
D000818:Animals; D003300:Copper / Q000737:chemistry / Q000633:toxicity*; D003621:Daphnia / Q000187:drug effects; D053758:Nanoparticles / Q000737:chemistry / Q000633:toxicity*; D016808:Tetrahymena thermophila / Q000187:drug effects; D014867:Water / Q000737:chemistry; D015034:Zinc Oxide / Q000737:chemistry / Q000633:toxicity*
D014867:Water; D003300:Copper; D015034:Zinc Oxide; C030973:cupric oxide