Chapter 31 In Vitro Testing of Inhalable Fly Ash at the Air Liquid Interface

The aim of this study is to analyse the toxicological potential of fine and ultrafine particles from industrial combustion processes using a biotest. This biotest is performed by near-realistic exposure of cultivated lung cells at the air-liquid interface and analysing the biological responses. Important steps in this work are to develop the exposure system for the use at industrial particle sources, to provide reproducible deposition conditions for submicron particles and to validate the exposure protocol for the bioassay. The presented technique maintains the viability of the cells but is sensitive for inflammatory effects. Exposure experiments with the ultrafine fraction of fly ash from a municipal waste incinerator have shown an increased release of IL-8 as a function of exposure time and dose. The presented exposure method and the lung specific bioassay seem to be an appropriate model to simulate the inhalation of particulate air pollution and to screen the biological effects of particulate emissions from different sources.