Correlations Between Water Hardness and Cardiovascular Deaths in Oklahoma Counties

Abstract

Significant negative correlations previously have been reported between total water hardness and cardiovascular disease death rates for the states of the US and the county boroughs of England and Wales. In the state of Oklahoma there is a wide variation in total water hardness and specific mineral concentrations (Na, K, Ca and Mg) between the counties in the eastern 1/3 and those in the remainder of the state. No similar significant negative correlations could be found when the total water hardness and specific mineral concentrations were compared with the age-sex-race-adjusted cardiovascular death rates in Oklahoma counties.