Water hardness and cardiovascular disease: A review of the epidemiological studies 1957-79

Introduction

Since publication of articles by Kobayashi (1957) and Schroeder (1960a, b; 1969), numerous epidemiologists throughout the world have studied the inverse (protective) association between drinking water hardness and cardiovascular disease mortality. Most investigators conducted ecological studies that considered population exposures to hard water and mortality statistics. Several community-intervention studies evaluated changes in mortality when drinking water hardness was increased or decreased. In more recent years, epidemiologists conducted analytical studies in which individual exposures and risk factors were considered.

Summarized in this chapter is the epidemiological literature published before 1980 and conclusions of scientific working groups convened by the National Academy of Sciences (NAS) and World Health Organization (WHO) during the 1970s.