Exposure of Human Nasal Epithelial Cells to Polycyclic Aromatic Hydrocarbons Differentially Increases Markers of Inflammation and Expression of Aryl Hydrocarbon Pathway Genes.

Inhalation of polycyclic aromatic hydrocarbons (PAHs) derived from emissions of solid waste combustion is of public health concern, as PAHs are associated with respiratory cancers and inflammatory diseases. Here, we chose seven individual PAHs associated with gene expression changes induced by exposure to plastic incineration emission mixtures in human nasal epithelial cells in vitro and further elucidated inflammatory cytokine release and expression of aryl hydrocarbon (AhR) pathway gene response by these PAHs and ranked their toxicities. Overall ranking analyses showed differential inflammatory and gene expression potentials among PAHs, with high-molecular-weight PAHs inducing responses greater than those of their low-molecular-weight counterparts. Observed findings causally link PAHs contained in combustion mixtures with biological responses and highlight the importance of understanding chemical profiles in combustion emissions to properly estimate the human respiratory hazard potentials.