Chemical quality of drinking water in Bahrain.

Chemical quality of five types of water used for drinking purposes in Bahrain were studied. There are three main sources of drinking water: tap, private treated, and bottled waters. The findings revealed that tap water had highest level of all chemicals studies (except silica) compared to other waters. Sodium level in tap water ranged from 100 to 545.9 mg/l, with an average of 309.4 mg/l. This average exceeds the drinking water standard as recommended by WHO (200 mg/l), making this water unsuitable for hypertensive people. Average level of fluoride ranged from 0.28 in carbonated mineral water to 0.85 mg/l in tap water. The high usage of bottled mineral water for drinking purposes may deprive the public, especially the children, from one of the protective elements (fluoride) for dental caries. This disease is highly prevalent in Bahrain. A programme to control chemical quality of drinking water in the country is highly recommended.