Functional Assessment of Threshold Parameters for Natural Mineral Water in China: Regulatory Comparison, Hydrogeological Context, Health-Related Evidence, and Label-Based Market Characteristics

Natural mineral water standards use compositional criteria to define product identity and distinguish natural mineral water from other drinking water categories. China’s National Food Safety Standard—Drinking Natural Mineral Water (GB 8537) specifies seven alternative minimum threshold parameters for this purpose. This study assessed how these parameters function in four dimensions: regulatory identity, hydrogeological resource recognition, health-related interpretation, and label-based market communication. We compared major international regulatory frameworks, qualitatively synthesized health-related evidence, reviewed representative source-scale hydrogeological evidence from China, and analyzed label information from 150 commercial products. China’s system differs from the Codex and European Union frameworks, which emphasize source authenticity, compositional stability, permitted treatment, and disclosure, and from the United States system, which primarily defines mineral water by total dissolved solids. Regional studies showed that mineral water composition reflects site-specific combinations of lithology, geological structure, recharge, groundwater circulation, and water–rock interaction. The same parameter may occur in more than one hydrogeological setting, whereas different parameters within one groundwater system may arise through distinct geochemical processes. Health-related evidence varies substantially and should not be interpreted as establishing consumer health claims. In the label survey, metasilicic acid, TDS, and strontium were the most frequently declared parameters, while zinc and free carbon dioxide were less frequently declared. We propose a functional framework that distinguishes statutory identity, hydrogeological resource, health/safety, sensory/technical, and consumer-communication roles. This framework clarifies why the seven parameters should not be treated as functionally equivalent and provides a basis for refining natural mineral water standards and label communication.