Major and trace elements in some bottled water brands from Khuzestan Province market, SW Iran, and accordance with national and international standards

Abstract

In this study, a total of 10 bottled water samples (10 brands) from natural springs and wells packed in 1.5 l plastic bottles were randomly purchased in Khuzestan Province market. The selected bottled water brands were analyzed for 40 parameters using ICP-OES, IC, HGAAS, spectrophotometric, titration and conductometric methods. Major and trace element concentrations differ among analyzed bottled waters, reflecting the different lithologies of the aquifers from which they are extracted. The studied bottled waters are classified as Ca–Mg–HCO₃ type according to Piper diagram, and as “low mineral concentration” type based on Van der Aa’s classification. The studied mineral water brands are classified as “very oligohaline”, “oligohaline”, and “fresh” water types with “very low” to “low mineral concentration” according to Stuyfzand’s classification. The amount of nitrate in two and three samples, falling in the range of 20–34 mg/l, exceeds its permitted levels according to Iranian national standard for natural mineral water and USEPA standards, respectively. Since Iranian national standard defines a permissive level for ∑(nitrate + nitrite), this total amount (>20 mg/l) exceeds its allowed level in three samples. All analyzed samples, however, are in accordance with WHO regulations regarding all parameters for which action levels are defined. The fact that nitrate concentrations in some bottled water brands are above the standard levels has no geologic reason, but it is due to human activities, especially the use of nitrate-bearing chemical fertilizers.