[Advances on the toxicology and molecular mechanisms of different components of ambient fine particulate matter]

Ambient fine particulate matters (PM_2.5) refer to particulate matters with an aerodynamic diameter less than or equal to 2.5 μm. PM_2.5 enter the body through the target organ-lung, and can induce a variety of adverse health effects (such as cardiovascular diseases, diabetes, respiratory diseases, neurodegenerative diseases and adverse birth outcomes). PM_2.5 are known to have complex compositions (including water-soluble/-insoluble components and biological components), diverse sources and capacity of secondary transformation. Numerous epidemiological and toxicological studies indicated that different components of PM_2.5 may induce adverse health effects through different biological mechanisms. In adddition, co-exposure of different components and their interaction should also be considered. Thus here we have systematically reviewed studies in recent years about the toxicological effects and underlying mechanisms of different components of ambient fine particulate matters, including inflammatory response, oxidative stress, endoplasmic reticulum stress, activation of the NF-κB signaling pathway and so on. The information may give some insights into the prevention and treatment of adverse health effects caused by exposure to different components of PM_2.5.