2013 Volume 76 Issue 3 Pages 207-214
Recently, new hot springs are born in Tokyo one after another. Most of these are artificial hot springs by digging deep under the ground on the bowling, and pumping up the deep water warmed by the heat source of geothermal gradient. Maeda et al. have investigated the ingredients in these hot springs of Tokyo 23 wards, and concluded that they are medically effective to promote health. It is unclear, however, how much these hot springs are medically effective compared to the well-known volcanic hot springs.
Thus, sodium-chloride type hot springs (Tokyo-A & Atami) and sodium-hydrogen carbonate type hot springs (Tokyo-B & Naruko) were chosen, and their analytical tables of chemical compositions were obtained from each hot spring resort through the Internet. Comparisons of the ingredients shown in the analytical tables were carried out to clarify difference between the artificial hot springs and the volcanic hot springs.
Since Tokyo-A and Tokyo-B do not belong to volcanic hot springs, their source temperatures are lower than the source temperatures of Atami and Naruko, and they do not contain various pharmacologically effective chemicals, such as sulfur compounds, free carbonate, etc. Furthermore, the modulation effects by the environmental factors such as hot spring location, climate, landscape etc. cannot be expected for the hot springs in Tokyo. However, the physical effects of hydrostatic pressure and buoyancy are expected in Tokyo-A containing large amounts of seawater components.
The most important medical effects of hot springs are considered to be suppressing active oxygen species and their activities, and repairing the cells damaged by the active oxygen species. From these points, although Tokyo hot springs have some healing effects, the medical effects as observed in the volcanic hot springs cannot be expected in Tokyo hot springs. For the establishment of balneology, the evaluations of each hot spring based on scientifically accurate information are required.
