Distribution and health risk of indoor and outdoor particulate polycyclic aromatic hydrocarbons and nitrated polycyclic aromatic hydrocarbons of a school classroom in Beijing, China

摘要

Polycyclic aromatic hydrocarbons (PAHs) have attracted much attention due to carcinogenic andmutagenic activities. Ambient PAHs come from a wide range of combustion sources, such as coal burning, vehicle exhaust,industrial and agricultural activities. During formation or after being emitted into the atmosphere, PAHs are rapidlyassociated with airborne particulate matters (PM) and involved in atmospheric processes. The derivatives of PAHs suchas nitrated PAHs (NPAHs) are more toxic than their parent PAHs because of the direct-acting mutagenicity, which can bereleased from the combustion sources with PAHs or formed in the atmosphere. PAHs carried by PM can be inhaled intothe human respiratory system, and finer particles (PM_(2.5)) can settle to deeper parts such as alveoli, causing respiratoryimpairments. Our previous studies have shown that particulate PAHs in Beijing were at high levels. Although theimplementation of air pollution control measures has reduced the emission of combustion, the pollution is still seriousand poses a threat to human health. Children are a susceptible group to air pollution. Their developing respiratory systemsare more sensitive to the stimulation of pollutants. Particularly, the damage caused by carcinogens and mutagens canhinder the development of children’s respiratory systems and increase the incidence of lung diseases in the future. Inaddition, school is one of the main places for children's activities, thus the PAHs concentration in schools plays animportant role in the development of their respiratory systems. However, few studies have focused on the health effectsof PAH compounds in PM_(2.5) in schools in Beijing on children. Thus, this preliminary study was conducted to investigatethe distribution characteristics of indoor and outdoor PM_(2.5)-bound PAHs and NPAHs in a school classroom in Beijing andthe health risks to children.