Comparison of two different devices for a 2-year toxicity study of multi-walled carbon nanotubes (MWCNT) in rats by repeated intratracheal instillations: a interim report at the end of year 1

Abstract

The present study was conducted to assess whether and how the use of different devices affect on the outcome of a 2-year toxicity study of MWCNT administered by intermittent intratracheal instillations. Male Fischer 344 rats (9 weeks old) were intratracheally administered MWNT-7 using a feeding cannula or a micro-sprayer, at a dose of 0.5 mg/kg BW every 4 weeks and examined at the ends of years 0.5 and 1 as interim sacrifices. While MWCNTs tended to be located in the caudal position of the lung lobes in cannula group, overall, no apparent difference was noted by the use of 2 different devices.