Beppu Onsen Seikaiso Uchiyu
Analysis UnverifiedGushing forth in Beppu, one of Japan's premier hot spring resorts, this water has long moisturized the skin of spa-goers. With a weakly alkaline pH of 8.2, the water gently envelops the skin like a beauty serum, softening it for a smooth feel. After bathing, you'll notice a supple texture and a warmth that radiates from your core. It's a healing spring, perfect for those seeking to reset mind and body away from daily life, or for anyone concerned about dry skin.
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.
- Chloride (salt)308 mg/kg
- Feel
- Tastes salty; the warmth lasts after you get out.
- Said to
- Salt is said to form a film on the skin that keeps in heat and moisture. Bathing indications include cuts, poor circulation and dry skin.
- Note
- May sting cuts. Strong salty water can tire you—avoid long soaks.
- Bicarbonate (baking soda)702 mg/kg
- Feel
- Your skin feels smooth and silky.
- Said to
- Said to remove old skin cells and excess sebum. Bathing indications include cuts, poor circulation and dry skin.
- Note
- It can leave skin dry—moisturize after bathing.
- Metasilicic acid140 mg/kg
- Feel
- Your skin may feel smoother.
- Said to
- 50 mg/kg or more is said to mark a “skin-beautifying spring”; it is also used in skincare.
- Note
- The “skin-beautifying” label is a common rule of thumb, not a legal standard.
- Source temperature52.3℃
- Feel
- The source is 42°C or hotter; the bath may be on the hot side.
- Said to
- Heat is said to boost circulation and warm the body.
- Note
- Older people and those with high blood pressure or heart conditions should avoid baths of 42°C or more. Keep soaks short.
Effects are general descriptions based on the Ministry of the Environment’s indications by spring type, not a guarantee.
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.
As the source is hot at 52.3°C, avoid long soaks. We recommend 'split bathing'—repeating 10-15 minute dips. The weakly alkaline water smooths the skin, but moisturizing after your bath will enhance its effects.
With a weakly alkaline pH of 8.2 and a high content of 139.7 mg/kg of metasilicic acid, known as a 'beauty ingredient,' this spring is associated with achieving silky skin by helping to remove old keratin. The chloride ions also form a thin veil on the skin, providing restorative warmth that prevents post-bath chills. It's the perfect onsen for days when you want to condition your skin and warm yourself to the core.
The water is hot, so be mindful of overheating and stay hydrated. Avoid bathing if you are not feeling well.
※ See the analysis data below for detailed contraindications
ANALYSIS DATAView all analysis fields ▼
Source Info
- Source name
- Beppu Onsen Seikaiso Uchiyu
- Spring type
- Sodium Bicarbonate and Chloride Spring
- Old spring type name
- 含食塩重曹泉
- Source temperature
- 52.3℃
- pH
- 8.2
- Osmotic pressure
- Hypotonic
Analysis Document
- Analysis date
- 2004-11-26
- Analyst organization
- 株式会社 住化分析センター 大分事業所
Cations
- Sodium ion Na⁺
- 399 mg/kg
- Potassium ion K⁺
- 41.4 mg/kg
- Magnesium ion Mg²⁺
- 8.2 mg/kg
- Calcium ion Ca²⁺
- 33.1 mg/kg
- Aluminum ion Al³⁺
- 0.00 mg/kg
- Manganese ion Mn²⁺
- 0.10 mg/kg
- Iron(II) ion Fe²⁺
- 0.00 mg/kg
- Iron(III) ion Fe³⁺
- 0.00 mg/kg
- Total cations
- 481 mg/kg
Anions
- Chloride ion Cl⁻
- 308 mg/kg
- Sulfate ion SO₄²⁻
- 21.0 mg/kg
- Bicarbonate ion HCO₃⁻
- 702 mg/kg
- Carbonate ion CO₃²⁻
- 30.0 mg/kg
- Total anions
- 1061 mg/kg
Undissociated Components
- Metasilicic acid H₂SiO₃
- 140 mg/kg
- Metaboric acid HBO₂
- 6.4 mg/kg
- Total undissociated
- 146 mg/kg
Dissolved Gas
- Free carbon dioxide CO₂
- 44.0 mg/kg
- Free hydrogen sulfide H₂S
- 0.00 mg/kg
- Total dissolved gas
- 44.0 mg/kg
Totals
- Total dissolved substances
- 1688 mg/kg
- Component total
- 1732 mg/kg
- Evaporation residue
- 1335 mg/kg
Usage
- Usage status
- Unknown
Indications & Contraindications
- Bathing indications
- Cuts and grazes, Peripheral circulatory failure, Poor circulation, Xeroderma, Depression
- General indications
- High blood pressure (mild), Rheumatoid arthritis, Autonomic instability, Insomnia, 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
