Risks of Single-Walled Carbon Nanotubes Acting as Contaminants-Carriers: Potential Release of Phenanthrene in Japanese Medaka (Oryzias latipes)

• Published in: Environmental science & technology 2013-05, Vol.47 (9), p.4704-4710
• Main Authors: Su, Yu, Yan, Xiaomin, Pu, Yubing, Xiao, Feng, Wang, Dongsheng, Yang, Min
• Format: Article
• Language: English
• Subjects: Agnatha. Pisces; Animal and plant ecology; Animal, plant and microbial ecology; Animals; Applied ecology; Biological and medical sciences; Carbon; Ecotoxicology, biological effects of pollution; Electrons; Environmental impact; Fish; Fresh water ecosystems; Fundamental and applied biological sciences. Psychology; General aspects; Nanotubes; Nanotubes, Carbon - toxicity; Oryzias; Phenanthrenes - toxicity; Polycyclic aromatic hydrocarbons; Synecology; Vertebrates: general zoology, morphology, phylogeny, systematics, cytogenetics, geographical distribution; Water Pollutants, Chemical - toxicity
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/es304479w

The performance of carbon nanotubes (CNTs) acting as contaminants-carriers in vivo is critical for understanding the environmental risks of CNTs. In this study, the whole-body accumulation and tissue distribution of phenanthrene in Japanese medaka was examined in the presence of single-walled carbon nanotubes (SWCNTs) and the potential release of phenanthrene was investigated from two types of SWCNTs suspensions that differed in surface charge and stability. The results showed that the coexistence of SWCNTs facilitated the accumulation of phenanthrene in the digestive track of fish and therefore enhanced the whole-body phenanthrene concentration by 2.1 fold after exposure for 72 h. Meanwhile, 6.4–48 and 20–34 times higher phenanthrene concentrations were measured in the liver and brain of fish exposure to the two mixtures, respectively, when comparing with the phenanthrene alone treatment with equal concentration of soluble phenanthrene. The extra phenanthrene was from the SWCNTs-associated phenanthrene that accumulated in the digestive track indicating the release of phenanthrene from SWCNTs did occur in fish. Moreover, the neutrally charged SWCNTs showed different agglomeration behaviors from the negatively charged SWCNTs, which could affect the accumulation of SWCNTs in the digestive track of fish and subsequently influence the retention of phenanthrene associated with the carbon nanotubes.