Malformations of Central Nervous System and Softness of Local Water Supplies

Abstract

The mean annual prevalence at birth of congenital malformations of the central nervous system for the three years 1964-6 in 48 local authority areas in South Wales was negatively correlated (r = -0.402, P<0.01) with estimates of the mean total hardness of the related water supplies.The mean annual perinatal mortality rate from anencephalus for the five years 1963-7 in 58 county boroughs in England and Wales was also negatively correlated with estimates of the mean total hardness (r = -0.220, P>0.05) and calcium content (r = -0.289, P<0.05) of the related water supplies.It is concluded that the relationship between these associations may well be secondary. Analytical epidemiological studies of the association are called for.