NIES Says PM2.5 Heavy Concentration Was Possibly Attributable to Transboundary Air Pollution from Asian Continent

According to the announcement by the National Institute for Environmental Studies (NIES) on February 21, 2013, it is highly likely that the heavy concentration of PM2.5, or hazardous particulate matters below 2.5 micrometers observed from January to early February 2013 throughout Japan was attributable to transboundary air pollution from the Asian Continent, and that a combination of transboundary pollution and urban contamination led to the increased concentration in large cities. This announcement was made based on a study of current observation data available and a simulation model.

The number of days when PM2.5 levels exceeding the environmental limit (daily average: 35 micrograms/cubic meter) were observed at any of the general ambient air pollution monitoring stations throughout Japan was 16. PM2.5 levels exceeding the environmental limit were observed at many stations in the Kyushu, Chugoku, Shikoku and Kinki districts.

NIES says that it is highly likely that the impact varies greatly with region and time, and a detailed analysis will be required in the future.

Related JFS article:
Tokyo Metropolitan Government's Efforts to Control Diesel Vehicle Emissions