Realistic Exposure Methods for Investigating the Interaction of Nanoparticles with the Lung at the Air-Liquid Interface In Vitro

In light of the increasingly abundant use of engineered nanoparticles (NPs) and the ongoing exposure to ambient ultrafine particles it is imperative that the potential for NPs to elicit adverse effects on human health is understood. In order to determine the potential harm that NPs may exert, many different in vitro systems have been used. Commonly in vitro nanotoxicology studies use NP suspensions applied directly to cell cultures. Although the use of in vitro monoculture systems to assess the effects of NPs on, for example, the lung is frequently debated, the use of suspension exposures is not realistic in relation to the exposure of NPs to humans via inhalation; the primary