In this figure you have the representation of the daily numbers of deaths and the daily levels of black smoke in London during the first 15 days of December 1952.

After a rapid decrease in temperature, levels of air pollutants, as represented by black smoke in this figure reached very high concentrations.

It has been generally agreed that about 4000 excess deaths resulted from the 1952 fog (Ministry of Health, 1954). Subsequent studies, however, have discussed such appraisal as they estimated about 12,000 exceeding deaths occurred from December 1952 through February 1953 because of acute and persisting effects of the 1952 London smog (Bell and Davis, 2001).

Besides the impact on mortality, those who were severely ill had histories of chest complaints, and in some cases hospital admissions for respiratory and cardiovascular causes quadrupled the expected rates.