Airborne particulate matters contain many kinds of organic pollutants. Among them, polycyclic aromatic hydrocarbons (PAH), nitropolycyclic aromatic hydrocarbons (NPAH) and quinoid PAHs were reported to have several human health effects. We collected airborne particulates in Kitakyushu, Japan and Tieling, China in summer and winter, and analyzed the PAH and NPAH to evaluate the direct- and indirect-acting mutagenicities and generating activities of reactive oxygen species (ROS). The concentrations of PAHs and NPAHs in Tieling were much higher than in Kitakyushu, with seasonal variations. The mutagenicity level was higher in winter while the ROS generation activity was higher in summer. These results suggest that concentrations of PAH and NPAH didn't correlate with mutagenicity and ROS generation activity. More studies are needed on the environmental behaviors of compounds other than PAHs and NPAHs, such as quinoid PAHs, and their biological activities.