Sodium intake has been linked with high blood pressure (hypertension). The principal source of sodium is from common salt (sodium chloride) used in food preparation. In fact no added salt is required in our diet, it is an acquired taste.
Sodium in town water is also a contributor to our daily intake, although it is debatable if the contribution from drinking water is significant when compared with our intake from food. There are two possible exceptions to this.
1. Waters derived from saline soils may have exceptionally high sodium levels, concentrations in excess of 1000 mg/l have been documented.
2. Ion exchange softeners which use salt for regeneration yield high sodium levels which can lead to dehydration in small babies. It is therefore very important that baby feeds are not made up using artificially softened water from ion exchange units.
It is not surprising that sodium salts can impart a salty taste to water, this is usually detectable at levels above 200 mg/l. The E.C. limit is set below this figure with a view to reducing the population’s sodium intake.
WHO limit = ---
EC guide level = 20 mg/l
EC MAC = 150 mg/l (from 1987 with percentile of 80)