In March, the air in Tokyo is polluted

Air pollution in Tokyo is not so bad thanks to exhaust gas regulation and factory discharge regulations. However, in March, some residents of Tokyo suffer from extreme air pollution.

Flying from mountain area

The causative substance of air pollution comes from the mountain area around Tokyo to the urban area. When a person of a specific constitution inhale this causative substance, symptoms such as a runny sneeze, eye itching and the like appear. There are many people in such a constitution in Tokyo, and it also becomes a big cause to lower the productivity of work at this time.


The identity of pollutants is a cedar pollen. Japanese cedar is widely used as a building material for Japanese houses and has been planted tremendously in the mountains throughout the country 70 years ago in order to revive the land that was devastated during the Second World War. Although it did not become a problem at that time, as the number of people who respond sensitively to cedar pollen increased, it is now becoming a social problem.

Weather forecast on pollen information

Currently, it is estimated that 30 million people are causing allergic reactions in cedar pollen in Japan. This is about 25% of the population of Japan, and so many people are suffering from cedar pollen. Since many people are interested in the pollen situation during this period, the weather forecast of the TV predicts the scattering situation of the pollen of the day and tells the audience.

The diameter of the dispersed pollen is 30 micrometers (about half the diameter of the hair), but on days with large amounts of scattering, it is visible that pollen deposits thinly on the road. Although there is no problem without pollen allergy, the desert sand flying from China also pollutes the air in Tokyo in the spring.

In spring, Tokyo air has low transparency.