A growing number of local governments, mainly in Kyushu, have started releasing observation data on the levels of air pollutant PM2.5 entering the atmosphere over Japan from China.
If necessary, some plan to issue warnings to residents and give advice on measures that can be taken to prevent possible ill effects from the particulate matter, because special alerts will be necessary from around early spring until June, when yellow sand is carried on the wind from China, further exacerbating the air pollution problem.
Since air pollution in China started to worsen in January, the amount of PM2.5 (particle matter 2.5 micrometers or less in diameter) rose in Kyushu. Some areas have had concentrations exceed the state-set daily average limit of 35 micrograms per cu. meter of air. A micrometer is one-millionth of a meter, and one microgram is one-millionth of a gram.
Local governments in Kyushu have received inquiries about the key pollutant and its possible health risks.
The prefectures of Fukuoka, Oita, Miyazaki, Kagoshima and Okinawa earlier this month began to post observation data, including hourly PM2.5 readings, on their websites.
Saga and Kumamoto prefectures began to release such data ahead of the other five prefectures, while Nagasaki Prefecture is set to follow suit and is now making preparations.
The Tokyo Metropolitan Government has also started to release data on the amount of PM2.5 in the air via Twitter.
On top of releasing observation data, some regional governments are set to issue alerts and advise residents on precautions.
Through emails, the city of Fukuoka plans to advise its citizens to wear face masks when going out and gargle after returning home if the concentration of PM2.5 as of 6 a.m. each day stands above 39 micrograms per cu. meter of air.
Tottori Prefecture also plans to alert residents via email if the hourly amount exceeds 35 micrograms.
The Environment Ministry has said current levels of PM2.5 nationwide will not immediately cause health problems. But the ministry is considering compiling guidelines on the pollutant as many local governments have asked it to come up with a table of standards on which they can base warnings to residents.