Mortality related to cold and air pollution in London after allowance for effects of associated weather patterns

Environ Res. 2001 Jul;86(3):209-16. doi: 10.1006/enrs.2001.4255.


We looked for atypical weather patterns that could confound, and explain large inconsistencies in, conventional estimates of mortality due to SO(2), CO, and smoke. Using Greater London data for 1976-1995 in the linear temperature/mortality range 0-15 degrees C we determined weather patterns associated with pollutants (all deseasonalized) by single regressions of daily temperature, wind, rain, humidity, and sunshine at successive days advance and delay. Polluted days were colder (P<0.01 for SO(2), CO, and smoke) and less windy and rainy than usual, and this cold weather was more prolonged than usual with 50% maximum temperature depression 5.9 days (95% interval 4.0-7.7) before high SO(2), compared to 2.0 (1.6-2.3) days before average cold days. We also used multiple regression of mortality at 50+ years of age on all these weather factors and pollutants at 0-, 1-, 2- to 4-, 5- to 13-, and 14- to 24-day delays to allow for the atypical weather patterns. This showed cold weather associated with 2.77 excess deaths per million during 24 days following a 1 degrees C fall for 1 day, but no net excess deaths with SO(2) (mean 28.0 ppb) or CO (1.26 ppm). It suggested (P>0.05) some increase with smoke, perhaps acting as surrogate for PM(10), for which data were too scanty to analyze.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Distribution
  • Aged
  • Aged, 80 and over
  • Air Pollution / adverse effects*
  • Air Pollution / analysis
  • Carbon Monoxide / adverse effects
  • Carbon Monoxide / analysis
  • Cold Climate / adverse effects*
  • Humans
  • London
  • Middle Aged
  • Mortality / trends*
  • Regression Analysis
  • Smoke / adverse effects
  • Smoke / analysis
  • Sulfur Dioxide / adverse effects
  • Sulfur Dioxide / analysis
  • Temperature
  • Time Factors
  • Weather


  • Smoke
  • Sulfur Dioxide
  • Carbon Monoxide