How Subway Station Dust Affects Your Health

   If you are a student of Ewha, you will have used the Ewha Womans University subway station (Ewha Station) from time to time. Let me ask you a question. In the station, when you wait for the train, how do you know when it's coming by signals or by sounds? In my case, I can tell by the dusty wind that blows in the station before the train arrives. The wind blowing there is quite unpleasant. The Seoul Research Institute of Public Health & Environment examined the dust levels of Seoul's most frequently used subway stations four times last year and announced their result on Feb. 21.
   The research showed the level of PM10 (Particulate Matters up to 10 micrometers), which is the air pollutant that most commonly affects people's health. Almost all the stations examined maintained levels under Korea? standard dust level which is 150 ㎍/㎥. In fact, the average dust level decreased from last year's 116 ㎍/㎥ to 100 ㎍/㎥. Seoul City credited their effort to clean the stations and new facilities they adopted for this improvement.
   Unfortunately, only one station exceeded the standard level, and that station happened to be Ewha station with 175 ㎍/㎥. Following Ewha station, City Hall, Dongdaemun, and Jongno 5-ga stations exceeded Seoul City? target level of 140 ㎍/㎥.
   There are many things floating around in the air. Most of them, you cannot even see. When you inhale, you breathe in air along with any particles that are in the air. The air and the particles travel into your respiratory system. The farther the particles go, the worse the effect. The smaller the particles, the better chance for them to stay in the system and travel farther. This is why the PM10 level is of primary concern to health agencies today. Not only does PM10 penetrate deeper and remain longer in the lungs than larger particles, PM10 also contains large quantities of organic materials that may have negative effects on people's health.
   Of course our lungs do have their own protective systems. Lungs produce mucous to trap the particles, and tiny hairs wiggle to move the mucous and particles out of the lung. The mucous leaves the airway by coughing or swallowing. However, if particles are very small and they get very far into the lungs, sensitive lung tissues may be exposed to their chemical actions, and this can result in lung disease, emphysema, and lung cancer.
   We know now how bad the air is in the Ewha station, but we cannot stop using the subway, nor can we stop breathing in the station. As a matter of fact, air pollution is a general problem in all urban areas. Still, this recent research gives hope that the PM10 level can be reduced by constant monitoring and effort.