Manufactured nanoparticles display physiochemical characteristics and impart unique electrical, thermal, mechanical, and imaging properties that are highly desirable for applications within the commercial, medical and environmental sectors. Carbon nanotubes exhibit excellent electrical, optical and chemical properties with a broad range of applications. In addition, surface modification of carbon nanotubes with organic functional molecules extends their already broad applications. The addition of organic coatings such as -COOH terminated coatings alter the charge, functionality, and reactivity of the nanotube. However, the development of these engineered carbon nanotubes has surpassed evaluation of the potential health impacts. Therefore, this study examines whether carbon nanotubes with different surface chemistry affects pulmonary toxicity. Mice (C57BL/6J, male,7 weeks old) were given 0-40 ug/mouse of either bare mulit-walled carbon nanotubes (MWCNT) or COOH-coated MWCNT via pharyngeal aspiration. Inflammatory and cytotoxic potential of each particle type was analyzed at 1 and 7 days post-exposure. The findings of this study show both the bare and the COOH-modified MWCNTs produced a dose dependent increase in PMNs harvested by whole lung lavage at both 1 and 7 days post-exposure. However, even though the COOHmodified MWCNT did produce a dose dependent increase in PMN number at all doses and at all post-exposure time points, the inflammatory response produced by the COOH-modified MWCNT was lower than the inflammatory response generated by the bare MWCNT. In conclusion, altering the surface functionality of the MWCNT, i.e. bare versus COOH-modified MWCNT lowered the inflammatory properties of the MWCNT.
Biological-effects; Environmental-control; Environmental-technology; Injury-prevention; Laboratory-animals; Laboratory-testing; Lung-disorders; Lung-function; Lung-irritants; Molecular-structure; Nanotechnology; Organic-compounds; Organic-dusts; Particulates; Pulmonary-function; Pulmonary-system; Quantitative-analysis; Respiratory-hypersensitivity; Respiratory-irritants; Respiratory-system-disorders; Risk-analysis; Risk-factors; Statistical-analysis; Toxic-dose; Toxic-effects; Toxic-materials; Toxins
The Toxicologist. Society of Toxicology 50th Annual Meeting and ToxExpo, March 6-10, 2011, Washington, DC