The truth about percutaneous toxicity: The "hidden dangers" revealed by a 699 yen hoodie and a Japanese quality solution

Hello, I'm Miko, the manager of Kokaiko Shoten!

Today, I would like to share with you a surprising incident that happened to me during a business trip to Hokkaido. Let's get started!

A shocking experience in Shimokawa, Hokkaido

After taking a train and a bus from Asahikawa, I arrived in Shimokawa, a small town in northern Hokkaido with a population of about 2,800.

In the past, there was a train that ran from Nayoro to Monbetsu, and there was also a station in Shimokawa, but the line was discontinued in 1989, and now there are only a few buses that run from Nayoro to Okoppe. On the day I arrived in this small town, it was a little chilly, and I was worried that my loungewear was thin.

Since this was the main destination of my business trip, I couldn't afford to get sick, so I rushed to the only supermarket in town.

So while I was shopping for dinner, I picked up a hooded sweatshirt in the discount clothing section that had suddenly popped up in the stores.

Price: Only 699 yen 

Material: 65% polyester, 35% recycled cotton 

Country of manufacture: China 

Manufacturer: Not specified

(I'm not saying that Chinese products are bad. There are a lot of high-quality Chinese products out there these days.)

I had no idea at the time that the piece of clothing I had bought, thinking it would just keep me warm, would later confront me with the reality that it was toxic to my skin.

There is not a single hotel-like establishment in Shimokawa Town, so we decided to stay at Mori no Naka Yokuru , a standalone accommodation that gives you the experience of living in a traditional Japanese home.

I checked in right away, took a bath, put on a T-shirt, and then put on the hoodie I just bought. After cooking and eating dinner, I spent a few hours in the room, and then my arms started to get itchy. I wondered if it was dry, and when I rolled up my sleeves...

After scratching it a bit...I was surprised!

My whole arm was swollen and bumpy like hives.

😱💥

Even though I am sensitive to chemicals, this happened so suddenly that I didn't check the material of the clothes, and I regret that. This experience is one that I will never forget.

📚 What is dermal toxicity? Science and reality

Definition and mechanism of percutaneous toxicity

Transdermal toxicity refers to harmful chemicals that enter the body through the skin. Many people think that the skin is a barrier that protects the body, but in reality the skin functions as a semi-permeable membrane, and chemicals with a molecular weight of 500 or less can easily enter the body.

Terrifying features of skin absorption:

• When taken orally : Approximately 90% is detoxified by the liver
• Absorption through the skin : Enters directly into the bloodstream and accumulates in the body without being detoxified

That's why I always recommend skin fasting and no shampooing because most cosmetics contain chemicals such as preservatives, thickeners, and synthetic surfactants, and it's very dangerous to let them penetrate the skin directly!

Related article - The fear of surfactants! Recommendations for going shampoo-free and skin fasting to avoid health risks

Now, let's get back to the topic.

The Hidden Truth of the Textile Industry

The modern textile industry uses thousands of chemicals to achieve beautiful color and functionality.

Major hazardous chemicals:

1. Azo dye system
   • Accounts for approximately 60-70% of the world's synthetic dyes
   • Potential to form 24 carcinogenic aromatic amines
   • It breaks down due to the pH of sweat and saliva, releasing toxic substances.
2. Formaldehyde Resin
   • Used for wrinkle and shrink prevention processing
   • WHO-certified carcinogen
   • Numerous cases of products for infants and young children exceeding standards
3. Heavy metals
   • Lead, mercury, chromium, cadmium
   • Serious effects on the nervous system, kidneys, and liver
   • Especially high concentration detected in recycled fibers
4. PFAS (Forever Chemicals)
   • Used for water-repellent and stain-resistant processing
   • Accumulates without being broken down in the body
   • Endocrine disrupting effects confirmed

What I should have looked for in this product wasn't the fact that it was made in China, but whether or not the manufacturer's name was clearly written on it.

For example, even if a product is made in China, if it is a global apparel brand such as MUJI, UNIQLO, or ZARA, they will always strictly inspect the raw materials used by the manufacturer. In that sense, it is not that products made in China are bad, but products that do not bear the name of the responsible manufacturer are truly scary .

Related article: Are menstrual pain and rough skin caused by sanitary napkins? Percutaneous toxins and the importance of organic sanitary napkins

The hidden risks of recycled textiles

Although recycled fibers are said to be good for the environment, they actually have many hidden dangers. For people like me who are sensitive to chemicals, using recycled products can be dangerous in some cases.

Sources of contamination during recycling:

• Foreign matter contamination during collection (metal pieces, plastic pieces)
• Residual chemicals from previous use (fabric softener, dyes, insect repellents)
• Strong alkaline and strong acid treatment during regeneration
• Excessive use of bleach

A study from the University of Valencia in Spain found:

• Formaldehyde concentration in recycled blended fibers: 12.7mg/kg
• Concentration of new organic cotton: 0.3mg/kg
• The difference is about 42 times!

Related article - Why I use toilet paper in the living room

🔬 Detailed Analysis of Dangerous Dyes

The threat of disperse dyes

Disperse dyes are chemicals used mainly for dyeing polyester fibers, especially for dark-colored clothing (navy blue, black, brown). (The sweatshirt hoodie I bought at that time was also navy blue.)

Top 5 high risk disperse dyes:

1. Disperse Blue 106 – the most potent allergen, the main cause of immediate urticaria
2. Disperse Blue 124 – Contact dermatitis, atopic dermatitis aggravation factor
3. Disperse Yellow 3 – Causes photosensitivity dermatitis
4. Disperse Orange 3 – Causes chronic eczema
5. Disperse Red 1 – Dermatitis with pigmentation

Stringent EU regulations:

• 31 types of disperse dyes to be restricted from 2009
• Special standards apply to children's clothing (under 36 months)
• Violators will be fined up to 4% of their annual turnover.

However, even if you have this knowledge, if the manufacturer is not listed, there is no way to pursue responsibility. That is why it is important that the manufacturer is listed.

Carcinogenic mechanism of azo dyes

While azo dyes provide beautiful colors, they can also have serious adverse effects on the human body.

Decomposition mechanism:

1. Enzyme action by sweat and saliva
2. Cleavage of azo bonds (-N=N-)
3. Formation of aromatic amines
4. DNA damage and carcinogenesis

Partial list of 24 restricted aromatic amines:

• 4-aminobiphenyl (bladder cancer)
• Benzidine (liver cancer)
• 2-Naphthylamine (kidney cancer)
• 4-Aminoazobenzene (blood cancer)

Dangerous substances that can lead to cancer! Be careful when buying cheap children's clothes and toys from the popular Chinese e-commerce sites! It would be scary if you put it in your mouth.

Related article: The scary traps lurking in the allure of Chinese e-commerce sites: What you need to know to minimize risk and shop safely

🛡️ A practical guide to protecting yourself from skin toxins

Check points before purchasing

1. Check to see if there is a third-party certification mark!

OEKO-TEX® STANDARD 100

• Class I (for infants and young children): The most stringent standards
• Class II (products that come into direct contact with the skin)
• Class III (products that do not come into direct contact with the skin)
• Class IV (Decorative materials)

GOTS (Global Organic Textile Standard)

• More than 70% organic fiber
• Processing with less environmental impact
• Compliance with social standards

2. How to read material labels

Display to avoid:

• "Anti-wrinkle processing" "Shape stability" → Possible use of formaldehyde
• "Antibacterial and deodorizing" → Uses silver ions and organic antibacterial agents
• "UV cut" → Uses ultraviolet absorbing agents
• “Water repellent finishing” → Use of PFAS chemicals

Safe viewing:

• "100% organic cotton"
• "Uncolored" "Ecru"
• "Using natural dyes"
• "GOTS Certification"

Chemical removal by washing

An effective initial cleaning protocol:

Step 1: Pre-wash

• Immerse in 40℃ warm water for 30 minutes
• Surface chemicals are dissolved using a surfactant (neutral detergent)

Step 2: Main wash

• Add oxygen bleach (chlorine bleach will damage the fibers)
• Set the washing time to 1.5 times the normal time
• Set the water volume to maximum to enhance dilution effect.

Step 3: Rinse thoroughly

• Twice the usual number of times (4 or more)
• Add 1 tablespoon of baking soda to the final rinse
• Residual detergent can also cause percutaneous toxicity.

Removal Efficacy Data:

• Formaldehyde: Approximately 85-90% removed
• Disperse dye: about 70-80% removed
• Heavy metals: Approximately 60-70% removed

Still, you can't remove everything.

There's no way to prevent this unless you are careful when shopping.

🌸 A solution based on Japanese craftsmanship

Why are Japanese products safe?

1. Strict legal regulations

• Chemical substance restrictions under the Household Products Regulation Act
• Quasi-drug certification under the Pharmaceutical Affairs Law
• Regular market surveys by the Consumer Affairs Agency

2. Inheritance of traditional techniques

• Natural dyeing techniques continued from the Edo period
• Quality control by hand by craftsmen
• Chemical-free manufacturing process

3. Corporate Social Responsibility

• High awareness of CSR (Corporate Social Responsibility)
• A corporate culture that puts consumer health first
• Quality improvement from a long-term perspective

💎 Carefully Selected Product Guide: The Best Choice for Skin Toxic Measures

NaturaMoon - Innovative technology to protect women's private parts

Development background: In 2012, amid growing demand from Japanese women for safe sanitary products, G-Place (now Japan Green Packs) spent three years developing this product. It is a groundbreaking product that is the first in Japan to combine a 100% natural cotton top sheet with no polymer absorbent material.

Technical features:

1. Topsheet Technology

• Made from 100% natural cotton nonwoven fabric
• No chemical adhesives
• Naturally bonded by heat processing

2. Absorbent design

• Uses cotton-like pulp derived from wood
• Completely free of polymer absorbent materials (SAP)
• Multi-layered construction for breathability

3. Organic Quality

• IFOAM (International Federation of Organic Agriculture Movements) certified ingredients
• Made with unbleached organic cotton
• No synthetic fragrances or colorants used

Clinical Data:

• Skin irritation test: Irritation index 0.0 (non-irritating)
• Allergy test: Sensitization index 0.0 (no sensitization)
• pH value: 4.5-5.5 (ideal pH for the intimate zone)

User experience (Woman in her 40s, living in Hong Kong): "For 20 years, I suffered from rashes caused by synthetic sanitary napkins. Since I switched to NaturaMoon, my stress during my period has decreased dramatically. I truly feel that this is 'Japanese quality.'"

Our lineup:

Safe for sensitive skin! NaturaMoon Sanitary Napkins (for heavy flow during the day, with wings) 16-pack

Safe for sensitive skin! NaturaMoon Sanitary Napkins (with wings for heavy nights) Pack of 10

Maruta Clothing – The ultimate sashimi technique recognized by sushi chefs

100 years of craftsmanship

Maruta Clothing, founded in the Taisho era, is a specialized manufacturer of "authentic sarashi" that continues to be loved by sushi chefs, Japanese confectioners, and medical professionals.

Manufacturing process features:

1. Raw material selection

• Made with 100% carefully selected domestic cotton
• Prioritize cotton grown in areas with low levels of pesticides
• Only long staple cotton with fiber length of 25mm or more is used.

2. Traditional weaving techniques

• Weaving on a power loom that has been in use since the early Showa period
• Density not achievable on modern high-speed looms
• Craftsmen check the quality of each and every piece

3. Natural finish

• No chemical bleaching agents
• Natural whiteness achieved by drying in the sun
• No fluorescent whitening agents added

Why choose us as a sushi chef:

• Water absorbency: 3 times that of a regular dish towel
• Quick drying: Prevents bacterial growth
• Durability: Can withstand hundreds of washes
• Food safety: No chemical residues

Versatile usage:

• Cosmetic uses : makeup remover, face mask cloth
• Nursing care use : Body wipes, diaper substitute
• Kitchen uses : Draining food, cooking cloth
• Cleaning purposes : window cleaning, floor cleaning

Our lineup:

• Shari-sarashi Large size (10 pieces): ¥1,925
• Shari-sarashi Medium size (20 pieces): ¥2,640
• Size: L (30cm x 40cm), M (20cm x 30cm)

It becomes a habit from those who use it! Sushi Chef's Exclusive Sarashi “Shari Sarashi” M size (20 sheets)

It becomes a habit from those who use it! Sushi chef's exclusive sarashi “Shari-Sarashi” L size (10 sheets)

Watanabe Series – Miracle body care created using Meiji era technology

No soap needed! A revolutionary body towel that removes sebum stains with just water

If you have read the article on percutaneous toxicity, then we have the perfect solution for you. The Watana series body towels are completely chemical-free and provide truly "skin-friendly" body care.

Why can dirt be removed with just water? The secret of Meiji-era spinning technology

1. Revolutionary spinning technology

• Uses traditional spinning machines handed down from the Meiji era
• Slow spinning takes 100 times longer than modern mass production
• Ultra-fine fibers (0.012-0.028mm) that contain plenty of air are completed

2. Scientific Mechanism

• Fibers thinner than the size of pores (approximately 0.2 mm) gently approach
• The fluff naturally absorbs and traps water and oil.
• No surfactant required, just removes the appropriate amount of sebum

3. The ultimate in pesticide-free cultivation

• Exceeds general organic cotton (no pesticides used for the past 3 years)
• Grown on farmland where pesticides have never been used
• 100% chemical-free manufacturing process

Good news for those with chemical sensitivities

Proof of complete additive-free:

• Pesticides: No pesticides used (strictly controlled from the soil level)
• Chemicals: Completely eliminated during manufacturing process
• Surfactant: No need to use
• Preservatives and fragrances: No added

The root cause of skin problems:

• Improving dry skin caused by "washing too much"
• Relief of atopic and allergic symptoms
• Restoring the skin's natural barrier function
• Naturally improves body odor caused by excess sebum

A real-life story from a woman in her 40s or older: "I suffered from dry skin for 30 years. Since I switched to Watabana towels, my skin has become smooth and the dryness has disappeared. I really feel the wonder of Japanese technology." (Woman, 45, Tokyo)

Artisanal quality

1. The pinnacle of sewing technology

• Each piece is handmade by a craftsman with 40 years of experience
• Technology to deal with special weaving methods that tend to unravel
• Precision work that requires one shot and cannot be resewn

2. Environmentally Friendly Design

• Zero waste with precise calculations in 5mm increments
• Short fibers are fully utilized without being wasted
• Cost savings through waste minimization

3. Pursuit of usability

• Unisex size (90cm x 16cm)
• Quick drying and comfortable
• Durability of 3 months or more

Use and Care

Basic usage:

1. Soak in water and squeeze lightly
2. Gently caress the body
3. After use, wash and dry in a well-ventilated place.

Advanced usage:

• No shampoo : Wash your hair with a mitten
• Care and nursing : Gentle care for those with sensitive skin
• Outdoors/Disaster Preparedness : Stay clean even without soap
• Skin Fasting : A life completely free of surfactants

Our lineup:

No soap required! 100% organic cotton body towel that removes sebum stains with just water [Watabana Series]

No soap required! 100% organic cotton body mitt that removes sebum stains with just water [Watabana Series]

A set of 2 organic cotton mini towels for washing dishes that can remove oil stains with just water.

This specially made 100% cotton mini towel can remove oil stains with just water. Organic cotton without pesticides or chemicals.

Removes sebum even without cleanser! 100% organic cotton face wash mini mitten (Watabana series)

🏥 How to deal with chemical sensitivity

Chemical substances exist everywhere in our living environment. Let's think about what measures we can take.

1. Environmental Control

• Removal of chemical substances from the living environment (detergents, fabric softeners, deodorants, etc. that contain petroleum-based surfactants)
• Use of air purifiers (air purifiers equipped with HEPA + activated carbon filters, etc.)
• Gradual switch to natural materials (from synthetic to natural fibers)

2. Nutritional Therapy

• Active intake of antioxidants ( enzymes , green tea , turmeric , etc.)
• Supports detoxification (using Yaeyama chlorella , roasted black rice tea , roasted black pickled plums , etc.)
• Improve your intestinal environment (actively consume fermented foods , natural fermented seasonings , etc.)

3. Stress management

• Breathing and meditation practice (from shallow to deep breathing)
• Moderate exercise (30 minutes of aerobic exercise + stretching and muscle training every day)
• Ensuring sufficient sleep (7-8 hours of sleep per day)

💝 Kokaiko Shoten: A bridge to Japanese quality

Our Mission

Kogaiko Shoten is not just an e-commerce site. We are a "cultural bridge that conveys the wonderful spirit of Japanese craftsmanship to the world" and we fulfill the following missions:

1. Strict quality standards

• Chemical substance testing for all products
• Direct communication with manufacturers
• Complete traceability

2. Educational role

• Providing accurate information to consumers
• Raising awareness of chemical risk
• Support for safe product selection

3. Transmission of cultural values

• Introducing traditional Japanese techniques
• Sharing the thoughts and stories of craftsmen
• Promoting a sustainable consumer culture

📝 Summary: Your choices will change your future

The lesson that the 699 yen hoodie taught us is that there is always a price to pay for cheap things . But it's not a hopeless story. With the right knowledge and the right choices, we can protect ourselves and our loved ones.

lastly:

We at Kogaiko Shoten will continue to serve as a bridge connecting people around the world with Japanese artisans, providing the highest quality products and useful information.

Each and every choice and action you make will help weave a beautiful future.

With this in mind, we continue to convey Japan's wonderful "monozukuri" spirit to the world today.