Hyotan Onsen
Analysis UnverifiedAn historic spring gushing forth in Kannawa, Beppu, one of Japan's premier onsen destinations. With an extremely high temperature of 97.5°C, this free-flowing spring holds the earth's powerful energy. The heat-retaining properties of this chloride spring ensure lasting warmth after your bath, gently enveloping a mind and body troubled by cold or fatigue. The weakly acidic water keeps the skin clean, while abundant metasilicic acid provides moisture. When you need to escape the daily hustle and warm yourself from the core, this onsen offers deep tranquility and vitality.
The bar length shows how abundant each component is compared to thresholds that make it "distinctive" (therapeutic spring standards, beauty spring criteria, etc.).
Undissociated boric acid with antibacterial action that keeps the skin surface clean.
A natural moisturizer also used in skincare lotions. Forms a thin veil on the skin to reduce moisture loss after bathing.
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 extremely hot at 97.5°C, so it's dangerous to touch the water directly from the spout. As a chloride spring with high heat retention, avoid long soaks and stay hydrated. It's best not to rinse off the minerals after bathing to let them absorb into your skin.
The weakly acidic water, with a pH of 3.11, is traditionally associated with soothing cuts and dry skin conditions. Abundant chloride ions envelop the skin like a veil, providing restorative warmth that may help with poor circulation and sensitivity to cold. Rich in metasilicic acid (476.6 mg/kg), it's also expected to offer balneotherapy benefits, leading to silky skin.
As this is a hot spring, individuals with severe heart, lung, or kidney disease, or high blood pressure should bathe with caution. Drinking is permitted, but due to arsenic content, the total daily intake should not exceed 111mL.
※ See the analysis data below for detailed contraindications
ANALYSIS DATAView all analysis fields ▼
Source Info
- Source name
- Hyotan Onsen
- Spring type
- Sodium Chloride Spring
- Source temperature
- 97.5℃
- pH
- 3.11
- Flow type
- Self-flowing
- Osmotic pressure
- Hypotonic
Analysis Document
- Analysis date
- 2016-04-08
- Analyst organization
- 株式会社 住化分析センター 大分ラボラトリー
- Registration No.
- 大分県第4号
Cations
- Lithium ion Li⁺
- 5.0 mg/kg
- Sodium ion Na⁺
- 1008 mg/kg
- Potassium ion K⁺
- 156 mg/kg
- Magnesium ion Mg²⁺
- 6.0 mg/kg
- Calcium ion Ca²⁺
- 41.9 mg/kg
- Aluminum ion Al³⁺
- 0.10 mg/kg
- Manganese ion Mn²⁺
- 1.3 mg/kg
- Iron(II) ion Fe²⁺
- 1.0 mg/kg
- Iron(III) ion Fe³⁺
- 0.40 mg/kg
- Lead ion Pb²⁺
- 0.00 mg/kg
- Copper ion Cu²⁺
- 0.00 mg/kg
- Total cations
- 1.2 mg/kg
Anions
- Fluoride ion F⁻
- 2.2 mg/kg
- Chloride ion Cl⁻
- 1574 mg/kg
- Sulfate ion SO₄²⁻
- 392 mg/kg
- Total anions
- 2.0 mg/kg
Undissociated Components
- Arsenious acid HAsO₂
- 1.3 mg/kg
- Metasilicic acid H₂SiO₃
- 477 mg/kg
- Metaboric acid HBO₂
- 60.7 mg/kg
- Total undissociated
- 0.54 mg/kg
Dissolved Gas
- Free carbon dioxide CO₂
- 0.00 mg/kg
- Total dissolved gas
- 0.00 mg/kg
Totals
- Total dissolved substances
- 3.7 mg/kg
- Component total
- 3.7 mg/kg
- Evaporation residue
- 3.6 mg/kg
Usage
- Heating
- No
- Dilution
- No
- Recycle / Filter
- No
- Additives
- No
- Disinfection
- No
Indications & Contraindications
- Bathing indications
- Cuts and grazes, Peripheral circulatory failure, Poor circulation, Depression, Xeroderma
- 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
- Drinking indications
- Atrophic gastritis, Constipation
- 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
- Drinkable
- Drinking notes
- この温泉はひ素を含むため、温泉飲用の1日の総量は111mLまでとすること。
