Japanese people are very sensitive about the air condition outside.
When spring comes, Japanese TV broadcasts the amount of those materials in weather reports.
Japanese people are very interested in the weather reports, because many people suffer from air pollution.
Japanese air is polluted by three materials in spring.
KOSA (yellow sand, size 1.0-5.0μm)
In March, many sands fly from China to Japan.
Those sands are originally came from desert in China and Mongolia.
Some people keep coughing and busy washing their car because of KOSA.
Kagoshima people usually don’t care about the KOSA, because they got used to the falling ash from Sakurajima.
I am proud of my hometown, Kagoshima!
PM2.5 (Particulate Matter, size about 2.5μm)
This is the chemical molecules and much smaller than KOSA.
Unlike KOSA, PM2.5 cannot be recognized by human eys.
PM2.5 flies from Chinese mainland.
This matters can cause diseases of lungs and other respiratory organs in human bodies.
Many people blame China as the cause of PM2.5 problems, but I didn’t have any problem when I lived in Beijing, China a few years ago.
KAFUN (Ceder pollen, size about 30.0μm)
The size is much larger than KOSA sand and PM2.5 matter. Many Japanese female (and some sensitive male) suffer from ceder pollen allergy.
More people suffer from KAFUN than KOSA. They cannot stop coughing and sniffing. Their eyes get very itchy.
My superior is one of those KAFUN sufferers. She gets very irritated when spring comes. I think that she should not take her spite out on me but on ceder pollen!
KAFUN (Ceder pollen) problems in Japan
Ceder trees are very soft and convenient for timber processing.
During the world war 2, Japan planted many ceder trees in order to produce papers and railways.
Even after the war, Japanese people keep planting ceder trees as materials for houses.
As a result, too many ceder trees were planted at Japanese mountains. Now, as much as 40% of Japanese forests are occupied by ceder trees.
Ceder trees keep producing pollens and make many Japanese people suffer from coughing and sneezing.