Acute toxic and cytogenetic effects of carbon nanotubes on aquatic organisms and bacteria

This paper summarizes a comprehensive study concerning the acute toxicity of a commercial carbon nanomaterial consisting mostly of carbon nanotubes to larvae of Chironomidae, crustaceans Ceriodaphnia affinis, algae Scenedesmus quadricauda, and bacteria Escherichia coli. It is shown that the nucleolar organizer region (NOR) index of polytene chromosomes in the salivary gland cells of midge larvae depends on the duration of concentration and exposure. This fact is indicative of the switching on of cell adaptation pathways in response to a xenobiotic stressor to restore cell homeostasis. The investigated nanomaterial is labeled as a Class III environmentally hazardous material (moderately hazardous). Safe concentrations of the carbon nanomaterial in aquatic media are less than 2 mg/L. It is concluded that larvae of Chironomidae are the most resistant to the material of all test species, whereas Scenedesmus quadricauda and Escherichia coli are the most sensitive.