Application of GasBench-IRMS and TC/EA-IRMS on Measurement of δD and δ¹⁸O in Mineral Water

Source regions of different mineral water largely determines their market value and price. To identify the authenticity of source regions, hydrogen and oxygen isotopes (δD and δ¹⁸O) of 11 different brand drinking water was measured through two methods of aqua equilibration technique (GasBench-IRMS) and the reduction of H₂O at high temperature (TC/EA-IRMS). Our results indicated that the measurement results of GasBench-IRMS were well consistent with those of TC/EA-IRMS. The difference were (0.6±1.59)‰ for δD, and (0.02±0.13)‰ for δ¹⁸O, respectively. Based on the GasBench-IRMS, more measurement time was required. However, it would give a better precision for δD and δ¹⁸O than that of TC/EA-IRMS. There were obvious changes in δD and δ¹⁸O of 11 different brand drinking water (including 8 kinds of mineral water). The δD and δ¹⁸O of different brand drinking water had notable regional features, which were mainly produced and influenced by local precipitation. Although the product authenticity could not be identify accurately, δD and δ¹⁸O of mineral water provided information about the water source for mineral water of special areas (e.g., high altitude and coastal regions). Through the database establishment of δD and δ¹⁸O in future studies, these results will gave implication for the quick water source identification for mineral water.