Kawa no Yu
Analysis UnverifiedKawa no Yu bubbles up naturally near the stream in the valley of Doroyu Onsen, a spa said to have opened in the early Heian period. Among the many self-flowing sources of differing character here, the Kawa no Yu source is the most mineral-rich: a near-neutral pH 5.8 hydrogen sulfide–type sulfur spring. Its bluish milky water swirls with white flakes and leaves sulfur deposits on the rocks, with a clinging, velvety feel that soothes those who seek a true sulfur bath.
The bar length shows how abundant each component is compared to thresholds that make it "distinctive" (therapeutic spring standards, beauty spring criteria, etc.).
The source of the distinctive sulfur smell. Dilates blood vessels via skin and inhalation to strongly boost circulation.
A natural moisturizer also used in skincare lotions. Forms a thin veil on the skin to reduce moisture loss after bathing.
Absorbed through the skin to gently promote peripheral circulation.
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 exceeds 77°C and stays hot near the spout even with added water; check the temperature and take short repeated dips. The hydrogen sulfide scent is strong, so keep the area ventilated and leave the bath at once if you feel unwell.
With 48.9 mg/kg of free hydrogen sulfide, this sulfur spring is traditionally associated with immune system stimulation in toji stays, and its 161.7 mg/kg of metasilicic acid may support silky skin that stays moist after bathing.
This spring is high in hydrogen sulfide; avoid long soaks in poorly ventilated spaces, stay out of restricted areas nearby and beware of the scalding spout.
※ See the analysis data below for detailed contraindications
ANALYSIS DATAView all analysis fields ▼
Source Info
- Source name
- Kawa no Yu
- Spring type
- Simple Sulfur Hot Spring (hydrogen sulfide type)
- Source temperature
- 77.4℃
- pH
- 5.8
- Flow type
- 自然湧出
Analysis Document
- Analysis date
- 2018-11-13
- Analyst organization
- 株式会社秋田県分析化学センター
- Registration No.
- 秋田第2号
Cations
- Lithium ion Li⁺
- < 0.1 mg/kg
- Sodium ion Na⁺
- 105 mg/kg
- Potassium ion K⁺
- 29.8 mg/kg
- Ammonium ion NH₄⁺
- 0.40 mg/kg
- Magnesium ion Mg²⁺
- 27.9 mg/kg
- Calcium ion Ca²⁺
- 43.9 mg/kg
- Aluminum ion Al³⁺
- 0.20 mg/kg
- Manganese ion Mn²⁺
- 0.50 mg/kg
- Iron(II) ion Fe²⁺
- < 0.1 mg/kg
- Iron(III) ion Fe³⁺
- 0.40 mg/kg
- Zinc ion Zn²⁺
- < 0.1 mg/kg
- Lead ion Pb²⁺
- < 0.05 mg/kg
- Strontium ion Sr²⁺
- < 0.1 mg/kg
- Barium ion Ba²⁺
- < 0.1 mg/kg
- Copper ion Cu²⁺
- < 0.1 mg/kg
- Cadmium ion Cd²⁺
- < 0.005 mg/kg
- Total cations
- 0.21 mg/kg
Anions
- Fluoride ion F⁻
- 0.90 mg/kg
- Chloride ion Cl⁻
- 167 mg/kg
- Hydrogen sulfide ion HS⁻
- 2.7 mg/kg
- Thiosulfate ion S₂O₃²⁻
- 7.3 mg/kg
- Sulfate ion SO₄²⁻
- 208 mg/kg
- Bicarbonate ion HCO₃⁻
- 36.5 mg/kg
- Bromide ion Br⁻
- 0.40 mg/kg
- Iodide ion I⁻
- 0.30 mg/kg
- Hydrogen sulfate HSO₄⁻
- < 0.1 mg/kg
- Nitrate ion NO₃⁻
- < 0.1 mg/kg
- Dihydrogen phosphate H₂PO₄⁻
- 0.10 mg/kg
- Total anions
- 0.42 mg/kg
Undissociated Components
- Sulfuric acid H₂SO₄
- < 0.1 mg/kg
- Arsenious acid HAsO₂
- < 0.1 mg/kg
- Metasilicic acid H₂SiO₃
- 162 mg/kg
- Metaboric acid HBO₂
- 0.80 mg/kg
- Total undissociated
- 0.16 mg/kg
Dissolved Gas
- Free carbon dioxide CO₂
- 95.4 mg/kg
- Free hydrogen sulfide H₂S
- 48.9 mg/kg
- Total dissolved gas
- 0.14 mg/kg
Totals
- Total dissolved substances
- 0.79 mg/kg
- Component total
- 0.94 mg/kg
Usage
- Heating
- No
- Dilution
- Yes（館内掲示『加水 有：源泉の温度が高いので加水しています』（天狗の湯・川の湯）。公式『加水・加温・減温の有無：加水あり』。大露天風呂（新湯）も温泉手帖で『気温により加水』。）
- Recycle / Filter
- No
- Additives
- No
- Disinfection
- No
Indications & Contraindications
- Bathing indications
- Atopic dermatitis, Plaque psoriasis, Chronic eczema, Epidermal suppuration
- General indications
- High blood pressure (mild), Rheumatoid arthritis, Autonomic instability, Insomnia, Depression, 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), Severe chronic dermatitis (sulphur springs)
Drinking
- Drinkability
- Not drinkable
