MORTALITY IN AREAS CONTAINING NATURAL FLUORIDE IN THEIR WATER SUPPLIES, TAKING ACCOUNT OF SOCIOENVIRONMENTAL FACTORS AND WATER HARDNESS

Data from M. A. Heasman and A. E. Martin's study of mortality and natural fluoride content of drinking-water have been reanalysed to take into account water hardness and four socioenvironmental factors (social-factor score, domestic air pollution, latitude, and rainfall). Correlations between mortality-rates and fluoride content tended to be weak and negative, and when socioenvironmental factors and water hardness were allowed for by calculating partial correlation coefficients no significant associations emerged.