Onyado Jin-no-uchi
Analysis VerifiedThis private source gushes forth in Yufuin Onsen, one of Japan's leading hot spring resorts. Nurtured in the tranquil environment of the Yufuin Basin, this source boasts a generous flow. The mildly alkaline water, with a pH of 8.5, is soft to the touch, clear, and gentle, making it appealing to everyone. Containing an exceptionally high 302.0 mg/kg of metasilicic acid, it is expected to leave the skin feeling moist and silky smooth after bathing. It is an ideal spring for those seeking a peaceful bath to release mind and body while feeling the grand nature of Mt. Yufu.
The bar length shows how abundant each component is compared to thresholds that make it "distinctive" (therapeutic spring standards, beauty spring criteria, etc.).
A natural moisturizer also used in skincare lotions. Forms a thin veil on the skin to reduce moisture loss after bathing.
A trace component with gentle antibacterial and anti-inflammatory action.
Scores are calculated from mineral analysis data based on the Mineral Spring Analysis Guidelines (Ministry of Environment, Japan). They are unrelated to facility atmosphere or service quality.
▸Note
The temperature, pH and component values shown here are based on the hot spring analysis (source). Actual values in the bath may differ depending on heating, dilution, recycling and filtration. Please check current usage status at the facility.
The source is very hot at 70.0°C, so the bathwater is adjusted to a suitable temperature. The alkaline simple spring with a pH of 8.5 is gentle on the skin, allowing for long, relaxing soaks. However, take breaks to prevent overheating.
The mildly alkaline water with a pH of 8.5 gently exfoliates old skin cells, leading to silky skin. Notably, it is extremely rich in metasilicic acid, a known skin-beautifying component, at 302.0 mg/kg. This is expected to leave your skin feeling moist and hydrated after bathing. As a gentle simple spring, it's also perfect for deep relaxation on days when you want to calm your mind and body.
Although the spring is mild, those who are unwell or have specific medical conditions should avoid bathing or consult a doctor. Be careful not to overheat from prolonged bathing.
※ See the analysis data below for detailed contraindications
ANALYSIS DATAView all analysis fields ▼
Source Info
- Source name
- Onyado Jin-no-uchi
- Spring type
- Alkaline Simple Hot Spring
- Old spring type name
- 単純温泉
- Source temperature
- 70℃
- pH
- 8.5
- Flow type
- 動力揚湯
- Osmotic pressure
- 低張性
Analysis Document
- Analysis date
- 2025-01-29
- Analyst organization
- 公益社団法人大分県薬剤師会
- Registration No.
- 大分県第3号
Cations
- Lithium ion Li⁺
- 0.30 mg/kg
- Sodium ion Na⁺
- 125 mg/kg
- Potassium ion K⁺
- 15.0 mg/kg
- Magnesium ion Mg²⁺
- 1.5 mg/kg
- Calcium ion Ca²⁺
- 9.8 mg/kg
- Lead ion Pb²⁺
- 0.00 mg/kg
- Barium ion Ba²⁺
- 0.10 mg/kg
- Copper ion Cu²⁺
- 0.00 mg/kg
- Cadmium ion Cd²⁺
- 0.00 mg/kg
- Total cations
- 0.15 mg/kg
Anions
- Fluoride ion F⁻
- 0.40 mg/kg
- Chloride ion Cl⁻
- 83.3 mg/kg
- Thiosulfate ion S₂O₃²⁻
- 0.30 mg/kg
- Sulfate ion SO₄²⁻
- 30.8 mg/kg
- Bicarbonate ion HCO₃⁻
- 188 mg/kg
- Carbonate ion CO₃²⁻
- 19.2 mg/kg
- Bromide ion Br⁻
- 0.20 mg/kg
- Hydrogen phosphate HPO₄²⁻
- 0.30 mg/kg
- Total anions
- 0.32 mg/kg
Undissociated Components
- Sulfuric acid H₂SO₄
- 0.00 mg/kg
- Phosphoric acid H₃PO₄
- 0.00 mg/kg
- Arsenious acid HAsO₂
- 0.10 mg/kg
- Metasilicic acid H₂SiO₃
- 302 mg/kg
- Metaboric acid HBO₂
- 4.3 mg/kg
- Total undissociated
- 0.31 mg/kg
Dissolved Gas
- Free carbon dioxide CO₂
- 0.00 mg/kg
- Free hydrogen sulfide H₂S
- 0.00 mg/kg
- Total dissolved gas
- 0.00 mg/kg
Trace Components
- Radon Rn
- 0 Bq/kg
Totals
- Total dissolved substances
- 0.78 mg/kg
- Component total
- 0.78 mg/kg
- Evaporation residue
- 0.57 mg/kg
Usage
- Heating
- No
- Dilution
- No
- Recycle / Filter
- No
- Additives
- No
- Disinfection
- No
Indications & Contraindications
- Bathing indications
- Autonomic instability, Insomnia, Depression
- General indications
- High blood pressure (mild), Rheumatoid arthritis, Chronic pain or stiffness in muscles and joints, Muscle stiffness due to motor paralysis, Gastrointestinal dysfunction
- Contraindications
- Acute illness (especially with fever), Active tuberculosis, Malignant tumors, Severe heart disease, Respiratory failure, Renal failure, Bleeding disorders, Severe anemia, Any actively progressing illness, Pregnancy (especially early and late stages)
Drinking
- Drinkability
- Not drinkable
