Impact of multi-walled carbon nanotubes on aquatic species

Abstract

To understand the environmental impacts of carbon nanotubes (CNTs), the toxicity study was carried out with water-soluble multi-walled carbon nanotubes (MWCNTs) using zebrafish (Danio rerio) as a model system. Zebrafish embryos were treated with different concentrations of MWCNTs. Teratogenic effects were evaluated through changes in embryonic development after 24 hours post-fertilization (hpf), 48 hpf and 72 hpf. No observable effect concentration (NOEC) was at 40 μg/mL. Lowest effect concentration (LOEC) of MWCNTs which caused significant phenotypic defects in zebrafish embryo was 60 μg/mL. At concentration above 60 μg/mL, slimy mucus like coating was observed around the embryo. At high concentrations, MWCNTs was found to be involved in the apoptosis, delayed hatching and formation of abnormal spinal chords. Thus, the toxicity of multiwalled carbon nanotubes is concentration dependent. Copyright © 2008 American Scientific Publishers All rights reserved.