Regulations governing diesel exhaust emissions have reduced air pollution in Tokyo significantly, according to a Tokyo metropolitan government survey.
Regulations governing diesel exhaust emissions have reduced air pollution in Tokyo significantly, according to a Tokyo metropolitan government survey.
The level of suspended particulate matter cleared the national environmental standard at 97 percent of checkpoints in fiscal 2004.
This is a drastic improvement from the previous fiscal year, when SPM levels made the standard at only 12 percent of checkpoints. The figure also surpassed the national average of 77 percent in fiscal 2003.
The latest results show Tokyo's air attained the level considered clean for the first time since fiscal 1984, when the metropolitan government began measuring SPM.
SPM is emitted by diesel-powered vehicles and is thought to be a cause of asthma, lung cancer and hay fever.
!ADVERTISEMENT!
The metropolitan government measures particulate levels at 34 checkpoints located along national highways and crossings and announces at how many of these sites the figure clears the national standard, which is a maximum of 0.1 milligram per cubic meter of air.
To see more of The Yomiuri Shimbun, or to subscribe to the newspaper, go to http://www.yomiuri.co.jp and www.yomiuri.co.jp/index-e.htm.
Source: Knight Ridder/Tribune Business News
