Water Quality Evaluation of PET Bottled Water by Mineral Balance in the Northeast Asian Region: A Case Study of South Korea

The past few years have seen a demand for drinking water in contemporary society with a focus on safety and taste. Mineral water is now marketed as a popular commercial product and, partly due to health concerns, the production and consumption of various mineral waters have steadily increased. In South Korea, where urbanization has progressed rapidly along with the country’s economic growth, the custom of drinking tap water directly from the faucet has decreased as the quality of city water has deteriorated. In Japan, in contrast, tap water can still be drunk directly from the faucet. However, due to fears related to water safety, to the popularity of super-soft water and to consumer preferences for hard water for dieting purposes, most drinking water comes from polyethylene terephthalate (PET) bottled water. One research study so far has been reported by Choi et al.1 who analyzed the mineral ingredients of South Korean PET bottled water for the whole country. However, the names of individual PET bottle brands were not mentioned. Moreover, this report1 analyzed PET bottled water that was purchased between 1995 and 1996, just after the sale of drinking water in containers in South Korea was permitted in 1994. It can be assumed that the PET bottled water samples studied included both newly sold water as well as water whose sale had been discontinued. As yet, there have been no articles about Korean bottled water published in English which deal with water indexes of taste and of health. The study here analyzed PET bottled water sold in LOTTE Mart in Seoul, a major South Korean bottled water supplier, with each PET bottle name clearly shown. For the study, a comparison was carried out of water samples from 9 types of PET bottled water sold in South Korea as well as from tap water in the cities of Seoul and Chuncheon. These were compared with samples of Japanese PET bottled water2, 3 in order to determine shared commonalities and identify individual characteristics. To evaluate water quality objectively, we quantified the elements contained in the water samples. Samples were assessed not with the usual sensory evaluation4 but with the evaluation approach advocated by Hashimoto et al.5, 6 which employs the Water Index of Taste and the Water Index of Health. The levels of water quality obtained were compared with the “Prerequisites for Tasty Water” and the “Standards for Tasty Water” devised for city water by the “Tasty Water Research Association” (Tokyo, Japan) of the former Japanese Health and Welfare Ministry.7