- Full (HTML) - Full (PDF) - Supplemental Material - Related EHP Articles - PubMed:Related Articles - PubMed:Citation - Cited in PMC - Purchase This Issue

Susanne Bastian,^1* Wibke Busch,^2* Dana Kühnel,^2* Armin Springer,^3* Tobias Meißner,^4* Roland Holke,^4* Stefan Scholz,² Maria Iwe,¹ Wolfgang Pompe,³ Michael Gelinsky,³ Annegret Potthoff,⁴ Volkmar Richter,^4** Chrysanthy Ikonomidou,^1** and Kristin Schirmer^2,5**

¹Department of Pediatric Neurology, University Children’s Hospital Carl Gustav Carus, University of Technology Dresden, Dresden, Germany; ²Department of Cell Toxicology, UFZ-Helmholtz Centre for Environmental Research, Leipzig, Germany; ³Max Bergmann Center of Biomaterials, Institute of Materials Science, University of Technology Dresden, Dresden, Germany; ⁴Fraunhofer Institute for Ceramic Technologies and Systems, Dresden, Germany; ⁵Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland

Abstract
Background: Tungsten carbide nanoparticles are being explored for their use in the manufacture of hard metals. To develop nanoparticles for broad applications, potential risks to human health and the environment should be evaluated and taken into consideration.

Objective: We aimed to assess the toxicity of well-characterized tungsten carbide (WC) and cobalt-doped tungsten carbide (WC-Co) nanoparticle suspensions in an array of mammalian cells.

Methods: We examined acute toxicity of WC and of WC-Co (10% weight content Co) nanoparticles in different human cell lines (lung, skin, and colon) as well as in rat neuronal and glial cells (i.e., primary neuronal and astroglial cultures and the oligodendrocyte precursor cell line OLN-93) . Furthermore, using electron microscopy, we assessed whether nanoparticles can be taken up by living cells. We chose these in vitro systems in order to evaluate for potential toxicity of the nanoparticles in different mammalian organs (i.e., lung, skin, intestine, and brain) .

Results: Chemical–physical characterization confirmed that WC as well as WC-Co nanoparticles with a mean particle size of 145 nm form stable suspensions in serum-containing cell culture media. WC nanoparticles were not acutely toxic to the studied cell lines. However, cytotoxicity became apparent when particles were doped with Co. The most sensitive were astrocytes and colon epithelial cells. Cytotoxicity of WC-Co nanoparticles was higher than expected based on the ionic Co content of the particles. Analysis by electron microscopy demonstrated presence of WC nanoparticles within mammalian cells.

Conclusions: Our findings demonstrate that doping of WC nanoparticles with Co markedly increases their cytotoxic effect and that the presence of WC-Co in particulate form is essential to elicit this combinatorial effect.

Key words: cellular uptake, cobalt doping, cobalt salt, human cell cultures, in vitro, nanoparticle behavior, toxicity, tungsten carbide nanoparticles. Environ Health Perspect 117:530–536 (2009) . doi:10.1289/ehp.0800121 available via http://dx.doi.org/ [Online 1 December 2008]

Address correspondence to K. Schirmer, Environmental Toxicology, Eawag, Überlandstrasse 133, 8600 Dübendorf, Switzerland. Telephone: 41-0-44-823-5266. Fax: 41-0-44-823-5311. E-mail: kristin.schirmer@eawag.ch

*These authors contributed equally to this article. **These authors contributed equally to this article.

Supplemental Material is available online at http://www.ehponline.org/members/2008/0800121/suppl.pdf

This research was supported by the German Federal Ministry for Education and Research within the project Identifizierung und Bewertung von Gesundheits- und Umweltauswirkungen von technischen nanoskaligen Partikeln (grant 03X0013C) .

The authors declare they have no competing financial interests.

Received 22 August 2008 ; accepted 1 December 2008.