Carbon Nanotubes are among the most promising materials for the technology industry. Their unique physical and chemical proprieties may reduce the production costs and improve the efficiency of a large range of products. However, the same characteristics that have made nanomaterials interesting for industry may be responsible for inducing toxic effects on the aquatic organisms. Since the carbon nanotubes toxicity is still a controversial issue, we performed tests of acute and subchronic exposure to a commercial sample of multiwalled carbon nanotubes in two fish species, an exotic model (Danio rerio) and a native one (Astyanax altiparanae). Using the alkaline version of the comet assay on erythrocytes and the piscine micronucleous, also performed on erythrocytes, it was verified that the tested carbon nanotubes sample did not generate apparent genotoxicity by means of single/double DNA strand break or clastogenic/aneugenic effects over any of the species, independently of the exposure period. Although, our findings indicate the possibility of the occurrence of CNTs-DNA crosslinks. Apparently, the sample tested induces oxidative stress after subchronic exposure as shown by activity of superoxide dismutase and catalase. The data obtained by the activity levels of acetylcholinesterase suggests acute neurotoxicity in Astyanax altiparanae and subchronic neurotoxicity in Danio rerio.

碳纳米管是技术行业最有前途的材料之一。它们独特的物理和化学特性可以降低生产成本并提高各种产品的效率。然而，使纳米材料在工业上引起关注的相同特征可能是引起对水生生物的毒性作用的原因。由于碳纳米管的毒性仍然是一个有争议的问题，因此我们对两种鱼类的一种多壁碳纳米管商业样本进行了急性和亚慢性暴露测试，这两种鱼类分别是外来模型（Danio rerio）和本地模型（Astyanax altiparanae）。）。使用在红细胞和鱼微核上进行彗星试验​​的碱性版本（也对红细胞进行了验证），证实了通过单/双DNA链断裂或在任何其他情况下产生的致胶性/无气性作用，被测碳纳米管样品均未产生明显的遗传毒性。种类，与暴露时间无关。虽然，我们的发现表明发生CNTs-DNA交联的可能性。显然，如超氧化物歧化酶和过氧化氢酶的活性所表明的，所测试的样品在亚慢性暴露后诱导氧化应激。通过乙酰胆碱酯酶的活性水平所获得的数据表明在急性神经毒性Astyanax altiparanae和亚慢性神经毒性在斑马鱼。