water hardness

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“Hard” water contains a high concentration of dissolved salts, notably calcium or magnesium salts, which inhibit the action of soap and therefore its cleansing quality. The geological composition of the catchment area determines the hardness or softness of the water supply from a particular source. Epidemiological evidence suggests that there may be an association between hardness or softness of drinking water supplies and the prevalence of certain conditions, e.g., cardiovascular disease, but the evidence is inconsistent and disputed.

Subjects: Public Health and Epidemiology.

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