道後温泉 第1分湯場
Dogo Onsen No. 1 Distribution StationSodium Bicarbonate-Chloride-Fluoride spring
- Sodium Na⁺
- salt's cation — pairs with chloride to make the water salty.
- Bicarbonate HCO₃⁻
- "soda" — softens skin, leaves it smooth.
- Aches & jointsstiff shoulders
- Smooth skindry, rough skin
- Recoveryfatigue, stress
Water drawn from Dogo Onsen's No. 1 distribution station, classified as an alkaline simple thermal spring. At pH 9.0 it is alkaline enough to give the slippery, soft feel that puts it squarely in Japan's beauty-water family. Dissolved solids are light at 274.7 mg/kg, so the water is gentle on the body, yet it still carries 52.3 mg/kg of metasilicic acid — the kind of silica film that leaves skin noticeably smoother afterwards. The posted indications lean to the classic simple-spring set: autonomic nervous system instability, insomnia, depressed mood and peripheral circulation disorders. The bath is disinfected with a chlorine-based agent to meet Matsuyama City's public bathhouse hygiene standard, but the water is neither diluted, reheated, nor recirculated.
Analyzed Dec 6, 2023·愛媛県立衛生環境研究所