Kunoshima Onsen on Ookunoshima island — classified as a weakly radioactive simple cold-mineral spring (hypotonic, neutral, cold-mineral). The wellhead emerges at just 19.5 °C, so the water is reheated for bathing rather than served at source temperature. Mineralization is light at 130 mg/kg of dissolved solids, which keeps the feel gentle and unobtrusive on the skin. The classification places it in the radon-spring family, the tradition associated with the so-called hormesis claim, and the certificate flags type-specific indications for gout, rheumatoid arthritis and ankylosing spondylitis.
Good for
Recovery
Warmth and buoyancy lower stress markers and improve sleep; habitual bathing is linked to lower rates of depression.
fatigue, stress
Take care
- 病気の活動期(特に熱のあるとき)
- Active tuberculosis
- 進行性の悪性腫瘍又は高度の貧血などの身体衰弱の著しい場合
- 少し動くと息苦しくなるような重い心臓又は肺の病気
- むくみのあるような重い腎臓の病気
- 消化管出血
- 目に見える出血があるとき
- 慢性の病気の急性増悪期
Full composition
The bar is each ion's share of charge (mval%) within its group; over 20% names the spring. Gases, silica and trace metals are measured by mass only.
- Sodiumsalt's cation — pairs with chloride to make the water saltyNa⁺14.5mgP3 national51%
- Calciumsettling and calming; can leave a white mineral bloomCa²⁺10.0mgP26 national41%
- Magnesiummild; a laxative if you drink itMg²⁺1.1mgP27 national7%
- PotassiumK⁺0.60mgP7 national0.8%
- StrontiumSr²⁺0.02mgP12 national
- Bicarbonate"soda" — softens skin, leaves it smoothHCO₃⁻39.1mgP23 national50%
- Chloridetable-salt anion — coats the skin and holds heat inCl⁻9.7mgP13 national21%
- Fluoridetrace; drinking limits applyF⁻4.4mgP75 national18%
- Sulfate"gypsum / Glauber's salt" — vessels and wound healingSO₄²⁻6.3mgP17 national10%
- NitrateNO₃⁻0.30mgP43 national0.8%
- Metasilicic acidmetasilicic acid — a natural moisturizer for silky skinH₂SiO₃42.8mgP24 national
- Free carbon dioxidefizz — widens blood vessels (strong above 1000 mg/kg)CO₂4.9mgP29 national
- ArsenicAsNDmg
- CopperCuNDmg
- Mercurytoxic trace — part of the drinking-safety checkHgNDmg
- LeadPbNDmg
Measured at the source
On the certificate
- 筋肉若しくは関節の慢性的な痛み又はこわばり(変形性関節症、腰痛症、神経痛、五十肩、打撲、捻挫などの慢性期)
- Muscle stiffness associated with motor paralysis
- 冷え症
- Peripheral circulation disorders
- 胃腸機能の低下(腹にガスがたまるなど)
- Mild hypertension
- Impaired glucose tolerance (diabetes)
- Mild hypercholesterolemia
- Mild asthma or emphysema
- Hemorrhoid pain
- ストレスによる睡眠障害(睡眠障害、うつ状態など)
- 高尿酸血症(痛風)
- 関節リウマチ
- Ankylosing spondylitis