OBJECTIVESTo clarify the characteristics of deep-sea water (DSW), we investigated the hematological, immunological and biochemical effects of DSW, specifically the so-called Japan Sea Proper Water (JSPW), samples of which we collected from the Japan Sea at a depth of about 300 meters.

METHODSFive groups of five mice each were orally administered,ad libitum for 12 weeks, one of the following: 1.2% DSW, 12% DSW, 1.2% surface-sea water (SSW), 12% SSW, or purified water (control)

RESULTSAmong these groups, no significant differences were observed in the average reduction of water intake, food consumption or body weight. The mean corpuscular volume, however, was significantly lower (p<0.05) in the 1.2% DSW group than in the control group. Moreover, serum immunoglobulin G and A values were significantly higher (p<0.05) in the 12% DSW and the 12% SSW groups, respectively, compared with the control group. In addition, the serum glucose value in the 12% DSW group was significantly higher (p<0.05) than in the control group

CONCLUSIONSThe findings of the present study suggested the presence of some toxic components in DSW. Before a final answer is reached about whether DSW, and specifically JSPW, is bad for human health, the pathophysiology of findings such as the decreased mean corpuscular volume, the higher immunoglobulin G value and the higher glucose value should be investigated.