In vitro toxicity assay using human bronchial epithelial cell, Beas-2B, for the screening of toxicological risk of dioxin-like compounds sampled from small sized Korean waste incineration plants.

To test the suitability of cell bioassay as a tool for screening the toxicological risk of dioxin-like compounds, an in vitro toxicity assay was performed using samples obtained from small sized Korean waste incineration plants. Stress-related gene expression, cell viability, apoptosis, DNA damage and cell cycles were investigated as toxicological indicators of the polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/DFs) exposed human bronchial epithelial cell, Beas-2B. Of the stress-related genes, the expressions of the aryl hydrocarbon receptor (AhR), cytochrome P450 (CYP) and p53 genes were most significantly induced by exposure to PCDDs/DFs. Exposure of Beas-2B cells to PCDDs/DFs sampled from waste incinerators was sufficient for the expression of noticeable cytotoxic and genotoxic effects. Increased number of cells in the G1 phase in PCDDs/DFs treated samples suggests PCDDs/DFs might lead to alteration in the cell cycle. Statistical tests revealed significant correlations between the PCDDs/DFs concentration and the AhR and CYP gene expression/cell viability/DNA damage. Different from AhR-mediated bioanalytical assay using genetically modified cell line, the present study has been focused on the evaluation of toxicological effects of dioxin-like compounds using normal human cell line. The results of this study have demonstrated that PCDDs/DFs samples from waste incinerators can be applied to cell bioassays for the evaluation of the toxicity of dioxin-like compounds obtained from field samples, and the use of stress-related gene expression assay and cytotoxic/genotoxic test systems would appear to be relevant for preliminary screening of the risk associated with dioxin-like chemicals from waste incinerators.