Maximal extent of translocation of single-walled carbon nanotubes from lung airways of the rat.

This study aimed to examine the extent of pulmonary translocation of single-walled carbon nanotubes (SWCNTs) from lung airways of rat. It utilised an ex vivo isolated perfused rat lung (IPRL) model that retains the intact lung architecture while eliminating the confounding issue of systemic pharmacokinetics. Doses (100 μg) of SWCNTs were instilled into the airways of the IPRL and the pulmonary translocation of SWCNTs quantified by inductively coupled plasma mass spectroscopy using CNT-associated nickel as the probe. SWCNT translocation from the airways across an intact pulmonary barrier into what would be the systemic circulation was no greater than 0.05% of the instilled dose over 90 min. Pharmacokinetic simulation incorporating a term for mucociliary clearance would predict over a 14 day an approximate cumulative pulmonary translocation from rat lung of no greater than 0.15% from a 100 μg deposited dose.