The season when the dense fog PM2 5 is coming①

In each of the cities in China, the arrival of a full-fledged winter, the heating by the poor quality coal combustion is applied, further "dense fog" (photochemical smog) by PM2-5 (micro particulate matter) is expected to occur frequently. Depending on the region, visibility has deteriorated to less than 50 meters even for a full year. In the northeast, Harbin is not seen five meters away. The effects of highway closures and flight cancellations and delays, as well as the impact on civil life, have been significant.

Especially, there is a concern about the remarkable health damage of the citizens. In the winter months in Beijing, the city has been covered with dense fog, so Japanese companies are taking precautions to refrain from going out to employees and other measures such as providing subsidies for purchasing air purifiers.

It is said that the number of expatriate employees who think about their families ' return home is increasing. In the first place, PM2-5 is a micro-particulate matter below the diameter 2.5 micrometer (Micro 1-millionth) contained in thermal power plants and plant smoke, automobile exhaust gases, fine dust, etc. Because it is easy to penetrate to the depths of the lungs, it induces asthma and lung cancer.

In the Japan of the high-growth period, Kawasaki Asthma and Yokkaichi caused asthma. Sulfur oxides (so 2) and nitrogen oxides (NOx) in PM2 and 5 are generated by burning coal, petroleum, etc. The main sources of sulfur oxides are steel mills, power plants, factories, etc. The source of the nitrogen oxide is similar to the sulfur oxide, other automobiles, ships, it is discharged in large quantities from the mobile sources such as aircraft. Dense fog in urban areas are due to sulfur oxides. Both are causative agents of air pollution, causing the collapse of ecosystems (planting and biological mortality), health hazards, etc. By the way, it is said that every year in China, about 500,000 people die from respiratory diseases.