Pollution characteristics, sources and health risk assessment of polycyclic aromatic hydrocarbons in PM2.5 in an office building in northern areas, China

Indoor Polycyclic Aromatic Hydrocarbons (PAHs) attached to PM2.5 have attracted attention because of their carcinogenic risks to human. The concentration of PAHs will increase coupled with PM2.5 during the heating season of northern region of China, which will directly influence physical and mental health or learning efficiency. Therefore, it is of great significance to study the pollution characteristics and sources apportionment of PAHs and assess the health risk to humans for controlling and improving indoor air quality. In the study, PM2.5 samples collected in an office building were used to measure PAHs inside during the heating seasons. With the measured concentration of PAHs as input, the carcinogenic risks to humans were obtained based on the health models. For comparison, PAHs during the non-heating seasons were also measured to analyze PAHs. According to the comparison results, outdoor coal combustion produced main contribution to indoor PAHs during the heating season. Though non-existent of carcinogenic risks to humans, the attention to the control of PAHs indoors will still not be neglected, especially the risks caused by Pyr, Bbf and Bkf through the dermal-contact and ingestion pathways.