Water Guide in Five Southeast Asian Countries

Vietnam, South Korea, Thailand, Cambodia, Philippines

🇻🇳 Vietnam

Drinking water is a major concern for any traveler or resident in Vietnam.
Although the country is developing rapidly, tap water quality remains problematic in most regions, including major cities like Hanoi and Ho Chi Minh City.

💧 Tap Water: Not Drinkable

Tap water in Vietnam is not safe to drink, even after basic home treatment. It may contain:

• Bacteria (coliforms, E. coli)

• Heavy metals (lead, arsenic in some regions)

• Residual chlorine, nitrates, and ammonia

• Rust and sediments from old piping systems

💡 Boiling water kills bacteria and some viruses, but does not neutralize chemical pollutants. Moreover, a quick boil (e.g., in an electric kettle) is not enough. It is recommended to bring water to a rolling boil for 1 to 3 minutes in a saucepan over high heat.

☕ Can you make coffee or tea with this water?

Yes, many Vietnamese people use boiled water to prepare coffee (especially the famous cà phê phin). However, for better health safety, it is recommended to use:

• Water filtered with a quality system (carbon filter, reverse osmosis), or

• Bottled water from reputable brands

👶 What water is safe for infants?

Pediatricians and health professionals strongly advise against using tap water—even boiled—for preparing baby formula.

✅ Instead, use:

• Low-mineral water (dry residue < 500 mg/L)

• Sealed bottled water labeled “suitable for infants”

• Reverse osmosis filtered water + boiling

📌 Recommended brands: Vital, Sapuwa, or imported options like Evian or Mont Roucous when available.

❌ Avoid high-mineral waters (such as Kim Bôi) unless medically advised — their high mineral content may strain an infant’s kidneys.

🧪 Special Water Types in Vietnam: Alkaline, Acidic, Mineral

Alkaline waters:

• Vikoda: Naturally alkaline mineral water, pH > 7.5

• Fujiwa: Marketed as “ionized water,” pH 8–9

These are popular for their digestive or pH-balancing effects, but not recommended for babies.

Acidic waters:

• Sometimes found in rural areas, especially from wells or rice fields (pH < 6)

• Often unsuitable for drinking without thorough treatment

High-mineral waters:

• Sources like Kim Bôi contain high levels of calcium, magnesium, and sulfates

• Beneficial for adults in moderation, but not suitable for infants

🥤 Sparkling Water in Vietnam – What You Need to Know

All Vietnamese sparkling waters are artificially carbonated.
There are no naturally sparkling water sources currently in use in Vietnam.

A few local brands produce sparkling water, often in limited quantities:

• Vĩnh Hảo Soda

• Bidrico Soda Water

• Vikoda Soda

Practical Recommendations

For a healthy adult, drinking bottled water is the simplest and safest solution.

For babies and vulnerable individuals, check the mineral composition and opt for tested brands.

For long-term stays, installing a home filtration system is an excellent option (4-stage filtration or reverse osmosis).

Be cautious with bottled water refills sold on the street or unsealed bottles—they may come directly from the tap without any treatment.

🇰🇷 South Korea

1. Tap Water: Drinkable but with Precautions

In South Korea, especially in Seoul, tap water is officially drinkable and meets quality standards. It is regularly tested and treated to remove bacteria and contaminants. However, many Korean households still use water filters, mainly due to mistrust of old pipelines or to improve the water’s taste.

For infants, it is recommended to avoid using hot tap water, which may carry residues from pipes. It is safer to use cold filtered or boiled water, especially for preparing baby bottles.

2. Local Bottled Waters

South Korea offers several local mineral water brands, mostly sourced from mountains or volcanic regions like Jeju Island. These waters are generally low in minerals and have a neutral or slightly alkaline pH, making them relatively safe for daily consumption, including for children—as long as the composition is checked.

Popular brands include:

• Samdasoo – A very pure volcanic water, widely used.

• ICIS – Sourced from protected natural springs.

• Sansu, Odaesan, and Sobaek Sansoo – All from mountainous regions known for their purity.

Some of these are suitable for infants if they are low in minerals, which depends on the batch or label information.

3. Baby-Specific Water

In Korea, there are waters specially designed for infants, usually distilled, purified, or very low in minerals. These can be found:

• In pharmacies

• Sometimes in supermarkets or organic stores

This type of water is recommended when a home filter is not used or when the child has special needs.

4. Waters by pH Level

• Neutral to slightly alkaline waters: The most common type. Suitable for gentle hydration, even for children.

• Alkaline waters: Sold by some health-focused brands, often via ionizers. Mainly intended for adults.

• Acidic waters: Very rare in South Korea and not recommended for consumption. Sometimes used in cosmetics but never for drinking.

• Very low mineral waters: Ideal for infants, as they protect the baby's still-developing kidneys.

5. Practical Advice

For infants, it is recommended to:

• Use purified, filtered, or distilled water

• Choose baby-specific water brands when available

• Carefully read labels to ensure low mineral content

• Avoid hot tap water, acidic waters, or waters with high mineral content

For adults and older children, most Korean bottled waters are perfectly fine for daily use, especially if they are slightly mineralized and neutral.

Recommended Korean Water Brands for Infants

In South Korea, for bottle preparation and baby hydration, it is advised to choose low-mineral, distilled, or purified water. Several brands meet these criteria:

• Jeju Samdasoo
  Volcanic natural mineral water, very pure and low in minerals. Suitable for infants if labeled “low mineral content.”

• ICIS
  Sourced from protected natural springs. Generally neutral and low in minerals. Considered safe for babies.

• Sansu (Jirisan)
  Natural water from the Jirisan mountain range. Usually neutral. Suitable for babies after checking the composition.

• Odaesan
  Mountain water, generally neutral. Can be used for infants if the label states “low mineral content.”

• Pulmuone Saemmul
  Some product lines are purified or distilled, specifically designed for young children—always read the label carefully.

• Sobaek Sansoo
  Mountain water, often pure and low in minerals. Choose only if explicitly indicated as infant-appropriate.

Baby-Specific Water

Some waters sold in pharmacies or large stores are clearly labeled “for infants” or “baby water.” These are distilled or ultra-filtered and guaranteed safe for bottle preparation.

Practical Tips

• Look for labels stating “suitable for infants” or “low mineral content.”

• Prioritize baby-specific water brands when available.

• If unsure, ask for advice at a pharmacy or check the manufacturer’s website.

These brands are widely available in South Korea and are known for their purity and safety when used for babies.

Korean Waters: A Complete Guide to Choosing Well

🇹🇭 Thailand

Tap Water

Tap water in Thailand, including Bangkok, is not drinkable in most areas. Although it is treated at the source, it often remains contaminated with bacteria or salt and may also contain heavy metals. Boiling the water can eliminate germs, but if it contains salt or metals, boiling actually concentrates these unwanted substances.
For making coffee or tea, it’s better to use filtered or purified water.

Local Bottled Water

The main bottled water brands in Thailand are: Aura, Mont Fleur, Purra, Crystal, Chang, and Singha. Each offers different water qualities, including natural spring water or purified water.

Water for Infants

For babies, it is strongly recommended to use bottled water that is low or very low in minerals. Some Thai brands meet this requirement and indicate it on the label (e.g., "Low Mineral", "Suitable for infants", or "For baby").
Commonly used brands for infants include:

• Mont Fleur Baby

• Crystal Baby (availability may vary by store)

• Nestlé Pure Life ("low mineral" version, subject to availability)

Some supermarkets also offer distilled water specifically intended for preparing baby bottles.
It is important to always check the label and choose water with mineral content suitable for infant feeding. Distilled water (pure and mineral-free) is another safe option for babies.

Specialty Waters

• Alkaline Water: Brands like Purra and 8PLUS offer high pH “alkaline” water.

• Acidic Water: Very rare, almost never consumed.

• Mineral-Rich Waters: Some brands contain more calcium or magnesium—check the label depending on your needs.

In Summary
Do not drink tap water. Prefer bottled water, and for infants, choose specific low-mineral or distilled water. Always read labels carefully to ensure the water’s quality and suitability for infant use.

🇰🇭 Cambodia: What You Need to Know

🚱 Tap Water: Not Recommended Anywhere in the Country

Even in major cities like Phnom Penh, Siem Reap, or Sihanoukville, tap water is not safe to drink.
It may contain:

• Bacteria (e.g., E. coli, fecal coliforms)

• Parasites

• Heavy metals (lead, arsenic, oxidized iron)

• Residual chemicals (improperly dosed chlorine, nitrates, etc.)

Why?

• Water treatment systems vary greatly between cities.

• Pipes are often old, leaky, or contaminated.

• Storage in home tanks or public reservoirs can lead to recontamination.

💡 Even after municipal treatment, water can become unsafe before it reaches your tap.

☕ For Making Tea or Coffee

✅ Yes — if boiled for several minutes.
✅ Better: use purified or bottled mineral water.

Note: The heat from tea or coffee is not enough unless the water has been boiled for at least 1 to 3 minutes.

🍼 Water for Infants
Avoid tap water entirely, even boiled, for:

• Baby bottles

• Purees or baby food

✅ Recommended:

• Low-mineral bottled water (e.g., Elan Purified, Kulen, or imported water like Evian baby)

• Reverse osmosis (RO) water purified at home

Always check the label:

• Dry residue (total minerals): under 100 mg/L

• Nitrates: under 10 mg/L

🧪 Specific Waters in Cambodia

✅ Local Mineral Waters:

• Kulen Water: From a spring at the base of Phnom Kulen mountain, available in still and sparkling.

• Elan Water: Purified water also available in alkaline form (pH > 8.5), produced in Cambodia.

⚠️ Acidic Water:
Some groundwater or rural wells may have very low pH (<6), making them corrosive and harmful to teeth, stomach, and infants.

⚠️ Over-Mineralized Water:
Avoid for babies.
Some local or imported waters may contain:

• Too much calcium or sodium

• Unbalanced pH

🇵🇭 Philippines: What You Need to Know

🚱 Tap Water: Not Safe to Drink, Even in Urban Areas

Even in major cities like Manila, Cebu, or Davao, tap water is not considered safe for direct consumption. The most common risks include:

• Pathogenic bacteria: E. coli, fecal coliforms, Salmonella

• Parasites: Giardia, amoebas

• Chemicals: residual chlorine, nitrates, and heavy metals in some areas

Why is it risky?

• Water supply can be irregular or exposed to leaks and cross-contamination

• Urban treatment systems exist, but don’t always ensure consistent water quality

• In rural areas, the situation is often worse — sometimes with no treatment at all

⚠️ Boiling kills bacteria, but not chemical contaminants or heavy metals.

☕ Water for Tea/Coffee

✅ Recommended:

• Filtered water (home filtration systems or from trusted dispensers)

• Properly boiled water (boiled for at least 2–3 minutes)

🔍 Since tea and coffee are very popular in the Philippines, many households use purified water to preserve both flavor and health.

🍼 Water for Infants

Tap water (boiled or not) is not suitable for babies:

• Too high in nitrates or minerals

• Risk of bacterial contamination

✅ Recommended:

• Distilled water (widely used in hospitals and pharmacies)

• Very low-mineral bottled water

👉 Popular brand: Wilkins Distilled Water (a Coca-Cola Philippines brand), widely used in maternity wards and supermarkets.

🧪 Specialty Waters Available

✅ Alkaline Water (pH > 8):

• Nature’s Spring Alkaline: pH between 8.5 and 9, marketed as good for digestion

• Aquadera Alkaline Water: a premium local brand available in select regions

👉 These are mostly used by people looking for detox or acid-alkaline balance effects.

⚠️ Acidic Water:
Rainwater may be acidic in areas with high air pollution.
However, commercial bottled water generally has a controlled pH, ranging from neutral to slightly alkaline.

✅ General Recommendations:

• Avoid boiling water in a kettle if it contains salt or heavy metals: this concentrates them

• Boiling kills germs but does not remove lead, arsenic, pesticides, or nitrates

• For coffee, use filtered or bottled water, especially for children or vulnerable individuals

• For babies, always choose low-mineral or specially labeled infant-safe water

Korean Waters: A Complete Guide to Choosing Well

🧾 FAQ – Drinking Water and Bottled Water in Asia
(Cambodia, Thailand, Vietnam, the Philippines, South Korea)

1. Why should you avoid drinking tap water in these countries?
In Cambodia, Thailand, Vietnam, and the Philippines, tap water is generally not safe to drink due to bacterial contamination, insufficient treatment, or aging pipes.
In South Korea, tap water is officially safe, but many locals still prefer filtered or bottled water due to concerns about taste or old plumbing.

2. What types of bottled water are available?
You can find:

• Natural mineral water

• Spring water

• Purified or distilled water (pure water)

• Alkaline or sparkling water (carbonated mineral water)

3. Where does bottled water come from?
Most bottled water comes from underground aquifers, naturally filtered through rock layers, then collected without chemical treatment.
These waters often contain natural minerals like calcium and magnesium.

4. What are bicarbonates and what are they for?
Bicarbonates are minerals that help regulate stomach acidity.
Waters rich in bicarbonates and magnesium are often recommended for digestion or post-exercise recovery.

5. Are there health benefits to drinking bottled water?
Yes. Waters high in calcium and magnesium support bone and cardiovascular health.
Some also contain beneficial trace elements (zinc, potassium, etc.).
⚠️ Be cautious with high-sodium or high-mineral waters for infants.

6. What does "PET" mean on water bottles?
PET is a lightweight plastic used for bottling.
PET bottles are recyclable and commonly found in supermarkets and convenience stores.

7. How many liters of water should you drink per day in these countries?
Due to the hot and humid climate, adults should drink 2 to 3 liters per day—more if physically active.

8. Does bottled water contain fluoride?
Sometimes. Some waters naturally contain low levels of fluoride.
Check the label to confirm the amount—excess fluoride can be harmful long-term.

9. Can I use a water filter pitcher instead of bottled water?
In South Korea and Thailand, a good-quality filter pitcher can improve tap water.
In Cambodia and Vietnam, it's safer to stick with bottled or delivered water jugs.

10. What is still water?
Still water is non-carbonated, without bubbles.
It’s the most common form of bottled water.

11. What’s the difference between spring water and mineral water?

• Spring water: Comes from a natural underground source and is naturally drinkable, but mineral content is not regulated.

• Natural mineral water: Has a stable and officially recognized mineral composition, validated by authorities (e.g., Academy of Medicine).

12. What about thermal waters?
Thermal waters come from hot springs rich in minerals.
Mostly used in skincare treatments or spas, though some are also bottled for consumption.

13. Does sparkling water contain added gas?
Sparkling mineral water contains carbon dioxide (CO₂):

• Either naturally occurring,

• Or added during bottling

14. Is bottled water quality-controlled?
Yes. Each country has potability standards, requiring:

• No harmful bacteria

• Safe levels of nitrates, fluoride, and heavy metals

Always buy bottles that are properly sealed.

15. What are the most common bottled water sizes?
Bottled water typically ranges from 330 mL to 5 liters.
The most common format in stores is the 1.5-liter PET bottle.

🔬 How Do These Substances Cause Cancer?

They act as mutagens, damaging the DNA of cells.

They can trigger chronic inflammation in vital organs (liver, intestines, bladder).

Heavy metals (e.g., arsenic, lead) accumulate in the body over time, disrupting cellular and immune functions.

📌 Important to Know:

Risk depends on exposure duration, concentration of toxins, and individual factors (e.g., genetics, immune strength).

A short-term exposure (e.g., during a trip) is unlikely to directly cause cancer, but certain contaminants like heavy metals may leave lasting traces in the body if not properly eliminated.

✅ What You Can Do:

Always drink filtered or bottled water in high-risk areas.

If staying long-term, consider a water quality test and install a proper water filtration system (e.g., carbon filter or reverse osmosis).

If exposed, get a medical check-up and monitor kidney and liver function regularly.

A Complete Guide to Choosing Well

IMPORTANT NOTICE: Tap Water Ingestion in Asia

⚠️ Health Warning

In many parts of Asia, tap water is not safe to drink according to European or international standards. It may contain pathogens (bacteria, viruses, parasites), chemical residues, or heavy metals due to inadequate treatment, aging infrastructure, or local contamination.

🚱 What Tap Water in Certain Regions of Asia May Contain:

• Bacteria: Escherichia coli, Salmonella, Shigella

• Viruses: Hepatitis A, Rotavirus, Norovirus

• Parasites: Giardia, Entamoeba histolytica

• Heavy metals: Lead, Arsenic, Mercury

• Chemicals: Pesticides, Nitrates

🕐 Time to Eliminate Contaminated Water from the Body:

This depends on:

• The amount ingested

• A person’s health status

• The type of pathogen

• The immune system response

Typically:

• Non-contaminated water is eliminated within 24 to 48 hours

• Infections can remain in the body for days to weeks, depending on the illness

⚠️ Can You Get Cancer from Drinking Tap Water in Asia?

Yes — drinking contaminated tap water in some parts of Asia (and globally) can increase the long-term risk of developing certain types of cancer, depending on the toxic substances present in the water. These are not immediate risks like infections, but rather the result of chronic exposure to carcinogenic agents.

🔬 How Do These Substances Cause Cancer?

• They act as mutagens, damaging the DNA of cells.

• They can trigger chronic inflammation in vital organs (liver, intestines, bladder).

• Heavy metals (e.g., arsenic, lead) accumulate in the body over time, disrupting cellular and immune functions.

📌 Important to Know:

• Risk depends on exposure duration, concentration of toxins, and individual factors (e.g., genetics, immune strength).

• A short-term exposure (e.g., during a trip) is unlikely to directly cause cancer, but certain contaminants like heavy metals may leave lasting traces in the body if not properly eliminated.

✅ What You Can Do:

• Always drink filtered or bottled water in high-risk areas.

• If staying long-term, consider a water quality test and install a proper water filtration system (e.g., carbon filter or reverse osmosis).

• If exposed, get a medical check-up and monitor kidney and liver function regularly.✅ Recommendations:

1. Never drink tap water, except in countries with reliable water treatment (e.g., Singapore, Japan).

2. Use only sealed bottled water (check the cap).

3. Boil and filter water if needed (minimum 3 minutes boiling).

4. Avoid ice and raw vegetables from questionable sources.

5. Use safe water even for brushing your teeth.

6. Carry probiotics, activated charcoal, or anti-diarrheal treatment in case of symptoms.

📌 In Summary:

Drinking tap water in Asia can lead to serious infections, long-lasting digestive problems, and may require prompt medical treatment. Prevention is the best protection.