Authentic identification of bottled drinking water origin based on carbon and oxygen isotopes of dissolved inorganic carbon and chemical composition

To identify the origin and product type of bottled drinking water sold in the market δ¹⁸ O_DIC and δ¹³ and C_DIC; of dissolved inorganic carbon (DIC), δ¹⁸O and δ²H valueand chemical indexes such as mineral elements (K, Ca, Na, Mg, Sr) and ion (Cl^-, SO₄^2-, HCO₃^-) in the bottled drinking water were analyzed in this paper. The origin of bottled drinking water in China were verified by using Fisher discriminant analysis (Fisher-DA). The results showed that δ¹⁸ O_DIC and δ¹³ C_DIC, δ¹⁸O and δ²H value of bottled drinking water from different origins were significantly different, and the content of mineral elements and anions varied widely which could be used for origin traceability. The discriminant accuracy of the DA model for origin verification of the bottled drinking water was up to 100%, and hydrochemical analysis could distinguish the type of the bottled drinking water. The first five of importance for origin traceability were K, Cl^-, δ¹³ C_DIC, δ²H and pH value according to the Normalizing importance analysis. Combining with stable isotope fingerprint, hydrochemical analysis and multivariate statistical model, the authenticity of bottled drinking water can be accurately distinguished, and therefore protect the legitimate rights and interests of consumers and maintain market fairness. (authors)