The relation of mortality in England and Wales 1969-1973 to measurements of air pollution.

The relation between mortality of people aged 45 to 74 and atmospheric smoke and sulphur dioxide in the county and London boroughs of England and Wales was investigated using data for the years 1969 to 1973. Weighted multiple regression analyses, which took into account a number of socioeconomic and climatic variables, showed no consistent relation of smoke or sulphur dioxide with mortality from all causes or with mortality from specified causes postulated a priori to be related to pollution. In particular there was no significant association between smoke and mortality rates for respiratory illness. Comparison with results from similar analyses of data for the two previous decades suggested that a decline in the strength of associations had occurred in parallel with declining levels of the pollutants.