Mortality and the concentration of elements in tap water in county boroughs in England and Wales.

Abstract

To explain the associations of water hardness and air temperature with area differences in ischemic heart disease mortality, samples, of tap water were obtained from homes in 61 county boroughs in England and Wales [United Kingdom], and the concentration of Ca and 12 other elements was estimated. Multiple regressions were calculated with the death rates from various causes as dependent variables and with the concentration of the elements in the tap water, mean annual temperature, mean annual rainfall, and a socioeconomic index as independent variables. The well known negative association between water hardness and ischemic heart disease was shown to be due to Ca, and none of 12 other elements examined appeared to contribute significantly to the association. Area differences in other causes of death also showed an association with Ca. There was little association between temperature and ischemic heart disease.