Urban Air Pollution - Air Pollution and Global Warming: History, Science, and Solutions - page 78

cities throughout Great Britain by Harold Antoine Des
Voeux ,amember of the Coal Smoke Abatement Society
in London. The term spread after Des Voeux presented
areport at the Manchester Conference of the Smoke
Abatement League of Great Britain in 1911, describ-
ing smog events in the autumn of 1909 in Glasgow
and Edinburgh, Scotland, that killed more than 1,000
people.
The smoke in smog at the time was due to emissions
from the burning of coal and other raw materials. Coal
was combusted to generate energy, and raw materials
were burned to produce chemicals, particularly soda
ash [Na 2 CO 3 (s)], used in consumable products, such as
soap, detergents, cleansers, paper, glass, and dyes. To
produce soda ash, many materials, including charcoal,
elemental sulfur, potassium nitrate, sodium chloride,
and calcium carbonate were burned, emitting soot, sul-
furic acid, nitric acid, hydrochloric acid, calcium sul-
fide, and hydrogen sulfide, among other compounds.
Emissions from soda ash factories were added to the
landscape of the United Kingdom and France starting
in the early 1800s.
Today, pollution resulting from coal and chemical
combustion smoke in the presence of fog or a low-lying
temperature inversion is referred to as London-type
smog . Some of the chemistry associated with London-
type smog is described in Chapter 10. Several deadly
London-type smog events have occurred in the nine-
teenth and twentieth centuries. These episodes, dis-
cussed briefly next, provided motivation for modern-
day air pollution regulation.

Figure 4.2. Daytime darkness during the 1952 smog
event along the Strand in London. Library of
Congress, Prints and Photographs Division, NYWT&S
Collection, reproduction no. LC-USZ62-114381.

of pollutants, particularly from combustion of coal and
other raw materials, were blamed for the disasters. Dur-
ing the 1952 episode, the peak mixing ratio of SO 2 (g)
and peak concentration of particulate matter were esti-
mated to be 1.4 ppmv and 4,460

4.1.6.1. London, United Kingdom
Several London-type smog events were recorded in
London in the nineteenth and twentieth centuries. These
include events in December 1873 (270-700 more deaths
than the average death rate for this period), January 1880
(700-1,100 excess deaths), December 1892 (1,000
excess deaths), November 1948 (300 excess deaths),
December 1952 (4,000 excess deaths), January 1956
(480 excess deaths), December 1957 (300-800 excess
deaths), and December 1962 (340-700 excess deaths)
(Brimblecombe, 1987).
The worst of these episodes occurred in Decem-
ber 1952, with 4,000 excess deaths. Although excess
deaths occurred in every age group, the greatest num-
ber occurred for those older than forty-five. People with
ahistory of heart or respiratory problems comprised 80
percent of those who died. During the episodes, temper-
ature inversions coupled with fog and heavy emissions

gm − 3 ,respectively.
(This compares with 24-hour federal standards in the
United States in 2011 of 0.14 ppmv for SO 2 (g) and
150 gm − 3 min

diameter.) The particle and fog cover was so heavy dur-
ing the event that the streets of London were dark at
noon, and it was necessary for buses to be guided by
lantern light (Figure 4.2).

for particulate matter less than 10

4.1.6.2. Meuse Valley, Belgium
In December 1930, a five-day fog event in the presence
of a strong temperature inversion and heavy emissions
of SO 2 (g) from coal burning resulted in 63 deaths and
6,000 illnesses, mostly during the last two days of the
pollution episode. The majority of those who died were