Embryonic toxicity changes of organic nanomaterials in the presence of natural organic matter.

TitleEmbryonic toxicity changes of organic nanomaterials in the presence of natural organic matter.
Publication TypeJournal Article
Year of Publication2012
AuthorsKim, K-T, Jang, M-H, Kim, J-Y, Xing, B, Tanguay, RL, Lee, B-G, Kim, SDon
JournalSci Total Environ
Date Published2012 Jun 01
KeywordsAdsorption, Animals, Embryo, Nonmammalian, Humic Substances, Nanostructures, Oryzias, Water Pollutants, Chemical

When elucidating the potential fate and bioavailability of nanomaterials (NMs) in an aquatic system, it is important to consider the interactions between NMs and natural organic matter (NOM). The present study compared the toxicities of carbon-based NMs, with disparate physicochemical properties, on Japanese medaka (Oryzias latipes) embryos after the addition of NOM. The measured embryonic toxicity parameters were mortality, malformation and hatching delay. Various physicochemical properties of water suspended fullerenes (nC(60)) and multi-walled carbon nanotubes (MWNTs) were modulated by organic exchange (Tol/nC(60)), stirring over time (Aqu/nC(60)) and acid treatment (f-MWNTs) followed by characterization. Tol/nC(60) produced relatively more hydrophobic surfaces and exhibited smaller closed spherical agglomerates than Aqu/nC(60). Acid-treated f-MWNTs displayed functionalized hydrophilic surfaces compared to raw MWNTs (r-MWNTs). The resultant embryonic toxicities, in the absence of NOM, were ranked in the order: f-MWNTs>Tol/nC(60)>Aqu/nC(60). As the NOM concentrations were increased, no changes in embryonic toxicities were observed on exposure of Aqu/nC(60) and r-MWNTs; whereas, the toxicities were reduced on exposure to Tol/nC(60) and f-MWNTs, due to a disappearance of hydrophobic primary spherical aggregates and partial coating, respectively. These data suggest that in the presence of NOM, the morphological differences of NMs, as well as their physicochemical properties, play a significant role in their reactions and subsequent medaka embryonic nanotoxicity.

Alternate JournalSci. Total Environ.
PubMed ID22542237
PubMed Central IDPMC4034258
Grant ListP30 ES000210 / ES / NIEHS NIH HHS / United States