Aug 12, 2025

Printing and Dyeing Natural Fibers

Not all cotton is created equal. There is a vast difference between conventional cotton and the prints and dyes in it, which makes up 99% of the world's cotton, and certified organic cotton and its processes, which is under 1% of the world's cotton.

Conventional cotton uses 16% of the world's insecticides and 7% of the world's pesticides. From harvesting to dyeing, weaving, and printing, the process involves heavy chemical exposure—so intense that factory workers often wear hazmat suits. Yet these same fabrics end up against our skin and our babies' skin for our bodies to absorb.

Organic fabric isn't enough. Dyes and finishes need to be GOTS or OEKO-TEX certified to ensure they're safe to wear. Firstly, unless you have organic fibers that are also organically processed you do not have an organic fabric. An organic fabric is one that is third party certified to the Global Organic Textile Standard. Fabrics – even those made with organic fibers like organic cotton IF they are conventionally produced and not produced according to GOTS – contain chemicals such as formaldehyde, azo dyes, dioxin, and heavy metals.

When “fiber reactive” dyes are used, they should be GOTS-compliant to ensure they adhere to the standard. Heavy metals are common components of fabric dyes; they are part of the dye and part of the fabric fiber as long as the color remains.

In GOTS cotton, synthetic pesticides, herbicides, and chemical fertilizers are not allowed in the growing process. This promotes soil health and reduces environmental pollution. GOTS restricts the use of toxic chemicals in processing, such as azo dyes, formaldehyde, and heavy metals.

Only approved, eco-friendly chemicals can be used during processing (spinning, dyeing, finishing, etc.) and biodegradable and low-impact dyes are encouraged. Certified toxin-free prints and dyes are the only way to ensure ethical standards - GOTS certification requires compliance with International Labour Organization (ILO) standards. Unless the factory is certified organic — even if it's made in the USA, it will not guarantee fair working conditions and chemical-free production.

Prints on Conventional Cotton

Conventional printed cotton is made with synthetic dyes & chemical finishes. These can release toxins through skin contact, sweat, and heat. Risks are higher for babies and pregnant women.

Once it's spun, woven, and sewn, conventional cotton is treated with azo dyes, formaldehyde, heavy metals in pigments, PVS and plastisol, softeners and brighteners - and none of it has to be disclosed on the label. In the US, there is no requirement to disclose any of these treatments. They're banned in the EU but still common in US fast fashion brands.

Azo Dyes → Linked to carcinogens when broken down in the body.
Formaldehyde → Used for wrinkle resistance; known skin irritant.
Heavy Metals (Lead, Cadmium) → Found in pigments; accumulate in organs.
PVC & Plastisol → Often used in screen printing; contains phthalates.
Heat from the sun, body warmth, or washing can accelerate chemical release. More exposure = higher absorption through your skin.

Chemicals in conventional cotton prints are specifically engineered to bond to the fibers so they survive hundreds of washes without fading — and that permanence means the toxins stay with the garment and continue to touch your skin. The claim that chemical dye components reduce by 60% after washing—is not supported by scientific evidence.

GOTS-certified organic printing still bonds the color to fibers, but it uses low-impact, water-based dyes, avoids formaldehyde resins, azo compounds, heavy metals, and PVC binders, requires thorough post-print washing to remove any residuals before the fabric is sold. Choosing clothing printed and dyed only with GOTS-certified organic dyes can give you peace of mind for you and your family.

Fiber Bonding by Design

In conventional textile printing (especially with reactive dyes, plastisol, and pigment inks), the dye or pigment is chemically bonded to the cotton cellulose molecule. These bonds are covalent in reactive dyeing — which means the dye literally becomes part of the fiber at a molecular level.

In pigment printing, the pigments are glued to the surface with resin binders (often containing formaldehyde or acrylic polymers) designed to withstand abrasion and laundering.

Heat Setting Locks It In

After printing, fabrics are usually heat cured at 300–400°F (150–200°C). It cross-links the chemical binders and "bakes” the pigment or plastic into the fiber surface. Once cured, the chemical is essentially plastic-coated into place, making it highly resistant to normal detergent washing.

Many printed fabrics are treated with fixatives (cationic resins) that: Improve colorfastness, reduce bleeding, increase stain resistance. These coatings are not water-soluble, so they don’t break down with home laundering — but they can slowly abrade off through friction, releasing micro-particles.

Just because the color doesn’t wash out doesn’t mean chemicals can’t leach. Friction, sweat, and body heat can release unbound chemical residues or cause surface finishes to migrate into the skin. Heavy metals in pigments don’t wash out because they’re bound inside the color particles themselves — but skin oils can help carry trace amounts into pores over time. Even trace exposure matters over the long term—especially when wearing clothing day in and day out.


Dye migration via sweat	Up to 55 ng/cm² absorbed during exercise (PubMed)
Azo dye percutaneous absorption	Up to 0.022 µg/cm²/hr via pig skin; lower on human skin (SpringerLink)
Benzothiazole permeation	Confirmed migration through synthetic membranes (PMC)
Heavy metals mobilized in sweat	High bioaccessibility: Cr 37.8%, Ni 28.5% (MDPI)
Heavy metal absorption & toxicity	Lead/nickel penetrate skin and cause cellular damage (PubMed)
Sweat/oil leaching plastic additives	Shows how additives are released & absorbed via dermal contact (The Guardian)

When it comes to our wardrobes, there's nothing better than having a simple, wearable wardrobe that takes you through every season of life - toxin free and long lasting to support you and your family. We are so grateful for organic dresses and everyday layers that are so soft and comfortable, pretty and functional, that we can live in them!