What is pollution "London smog" that brought out the worst-case victims in history?


Very dense smog occurred in London between 5th and 9th December 1952 caused serious damage to respiratory organs and bodies of the inhabitants and put out a total of 12,000 victims. This is later "Large smog in 1952"London smogAs air pollution, it is the worst pollution ever in history.

Persistent sulfate formation from London Fog to Chinese haze

Scientists have have figured out the terrifying reason London fog killed 12,000 people - ScienceAlert

As Paris is called "City of Flowers", London is called "City of Mist", but "Fog" here means "Fog (fog)" in which the whole city is covered white in the morning It is "smog" that wraps around the city in a thin and dimly-lit manner. The word "smog" for the first time came out in the world is a sentence written by "a witty English writer" in the Los Angeles Times on January 19, 1893. However, in general, a doctor Henri Antoine de Vaux who published a paper "Fog and Smoke" at the Public Health Association held in 1905 pointed to the word "fog" seen in London (SmOke + fOg) It is said that it is.

It was coal that was creating the cause of smog. The relationship between coal and human race is old, and in coal and Shenyang coal made ornaments of Neolithic era (4000 BC) have been found. In the Fushun mine in China there is a record used as a fuel to dissolve copper around 1000 BC, and in the 2nd century the Romans are carrying out coal mining at the current Staffordshire. However, trees and charcoal were mainstream for a long time,

Coal mining that had been done in Britannia (now the UK) such as Staffordshire seems to have been burned down after Rome lost Britannia, and it seems that the record has been discontinued around the 10th century. However, in the 13th century I regained my liveliness. And from this period London has come to be said "air quality is bad".

In England the dependency on coal is steadily increasing as wood used as fuel can not be taken out earlier than in other areas, and in 2005 5/6 of the world's coal was mined in the UK . And the situation of the atmosphere has also worsened. "If the coal can not be used as an energy source, in the 1830s the place suitable for the water mill will have been gone" will also be expressed by the industrial revolution, which is also expressed in the Victorian era of London, later called the smog Occasionally occurred, it was suitable for being called "the capital of fog" exactly.

The relationship between air pollution and health damage has been known for a long time, and the number of dead was announced in the 19th century. In 1909 more than 1,000 people died in Glasgow and Edinburgh. Even then, chronically sacrificing continued, its peak was "Great Smog of 1952".

ByLeonard Bentley

In December 1952, London was covered with high pressure, a cold fog came out, and the citizen used more coal than usual for heating. As well as helping the windless state, soot became a thick smog layer over London. Its strength was about such that "the front can not be seen, the car can not drive, the traffic is confused", "the opera can not be seen at the theater and the performance is canceled". Due to the influence of high pressure and windlessness, smog kept staying in London for 5 days, during which time harmful substances spread all outdoors and indoors. It was unfortunate that at this time, the transport network in the city of London had been converted from trams to diesel buses, the amount of coal used was higher than before.

The number of deaths per day until smog got out was about 300 people, but when smog occurs more than 400 people died on the day, and the situation that the maximum of 900 deaths a day at maximum I fell into it. Smog disappeared when the weather changed on December 9, but the number of people who died so far is 4000 people. Also, even if smog disappears, the mortality rate did not return to the number before smog occurrence, the government initially thought that the person who died after smog disappeared is due to influenza, but its mortality rate is It was about 4 times higher than the number in the winter of 1953 next year, and it was necessary to doubling the mortality rate in order for this number to die with influenza.

Health effects study on air pollution | Environmental cure No. 21 | National Institute for Environmental Studies

Lessons learned from this, the London City Law was enacted in 1954, the "Atmospheric Purification Law" was enacted in 1956 and 1968, and the use of the fireplace was prohibited.

However, in fact, I did not know the details of the chemical part of how the substance released after burning coal penetrates the fog. This is the team of Mr. Rainy Chan and others of Texas A & M University.

The team is now investigating in Beijing and Xi'an, which is suffering from air pollution right now. As a result, it became clear that sometimes sometimes sulfate can be formed by mixing water droplets of mist mixed with NO 2 (nitrogen dioxide) and SO 2 (sulfur dioxide). As the mist evaporates, the remaining sulfate is concentrated to become "concentrated sulfate particles", which harm people, and even after the smog is gone, it can cause strong acid rain.

However, there is one big difference between "London smog" and smog occurring in China. That's why London smog is strongly acidic while Chinese smog is neutral.

When examining this in detail, it was similar to the case in London as far as SO2 is generated from the power plant and NO2 is generated from the car, but in China, mass production of nitrogen fertilizer by rapid growth and urbanization · We have been using a large amount of NH 3 (ammonia) has been found to be released in large quantities.

China does not leave air pollution as it is, but we are focusing on regulating SO 2 emission, but Mr. Zhang and others point out that regulating NO 2 and NH 3 emissions is also effective for sulfate formation countermeasure did.

I hope the day will come soon that the smog of China will be recounted as "There was such a time" as London became "City of Smog".

ByPeter Mackey

in Note,   Science, Posted by logc_nt