Toxic effects following phosgene exposure of human epithelial lung cells in vitro using a CULTEX® system.

The aim of the present study was to investigate toxic effects following phosgene exposure of human epithelial lung cells (A549) in vitro using a CULTEX® system. In particular, toxic effects regarding early biomarkers emerging during the latency period following exposure might be of great value for medical treatment. Cells cultured on semi-permeable membranes were directly exposed at the liquid-air interface to different concentrations of phosgene, or dry medical air. Cell membrane integrity (leakage of LDH), metabolic activity (reduction of Alamar Blue), oxidative damage (GSH, and HO-1, in cell lysates), and release of IL-8, were studied. For most of the above-mentioned biological end-point markers, significant changes could be assessed following a 20 min exposure to 1.0 ppm and 2.0 ppm phosgene. Moreover, except for IL-8, all biological marker profiles showed to be in line with results obtained by others in animal studies. The C×t value of 40 ppm min appeared to be constant. The overall results suggest that at 4 h post-exposure a maximal level of toxicity was achieved. Our results demonstrate the suitability of a CULTEX® system to detect toxic effects induced by phosgene on human epithelial lung cells, which may contribute to the discovery of early biomarkers for new medical countermeasures.