Ta-Chih Hsiao, a professor at NTU Graduate Institute of Environmental Engineering(left), and Kai-Hsien Chi, a professor at NYCU Institute of Environmental Health Sciences
A research team from National Taiwan University (NTU) and National Yang Ming Chiao Tung University (NYCU) investigated pm in an urban area and found that its substances including organic aerosols, iron, manganese, and copper, all of which increased cellular oxidative potential.
The research team monitored air quality for one month at a station in NTU near Keelung Road and observed that the largest fraction of pm composition, which is commonly known as secondary inorganic aerosols, comes from photochemical reactions of vehicle exhaust emissions. Secondary inorganic aerosols and black carbon, metal particulates produced from frequent braking—nonexhaust emissions—were verified by the research team to have similar adverse effects on human health.
Ta-Chih Hsiao, the leading researcher of this project and a professor at NTU Graduate Institute of Environmental Engineering, suggested that pm is harmful to the human body because human cells can be damaged when an excessive amount of active oxygen species from such matter accumulates in the cells, which is commonly known as free radical accumulation. According to the research, secondary inorganic aerosols, black carbon, and metals in pm were all possible causes of oxygen oxidative potential increase.
Kai-Hsien Chi, who was responsible for analyzing the components and toxicity of pm in the research and a professor at NYCU Institute of Environmental Health Sciences, pointed out that the measured mass concentration of pm failed to reveal the holistic picture of its risks and that the correlation between the mass concentration and cellular oxidative potential was weak. A further investigation into the cellular oxidative potential of pm components is required to provide more air quality information.