Think about the eight hours you spend tucked into your pajamas each night — the fabric that presses against your skin through every stage of sleep, through every quiet hour of restoration. Most of us give that fabric far less thought than we give the sheets we slide under or the pillow we settle into. But what your sleepwear is made of, and how it was processed, matters in ways that are easy to overlook. OEKO-TEX certification exists to answer a question most fabric labels won't: Has this textile been tested for harmful substances? Issued through the OEKO-TEX® Association's network of independent testing institutes, OEKO-TEX® STANDARD 100 certification means textiles have been tested for harmful substances. When you see the OEKO-TEX STANDARD 100 label on sleepwear, that means every thread, button and accessory of the article has been tested for harmful substances. At Eberjey, the Gisele TENCEL™ Modal Long PJ Set and the Inez Washable Silk Long PJ Set are verified by OEKO-TEX® Standard 100.
What Exactly Is OEKO-TEX, and Who Issues the Certification?
OEKO-TEX® is an international association of independent textile research and testing institutes. The certification is not self-reported by brands — third-party laboratories affiliated with the OEKO-TEX Association test fabric samples for harmful substances, and certification must be renewed to stay valid.
The OEKO-TEX family of certifications has expanded over the years:
- OEKO-TEX STANDARD 100 — product-level certification; every component of a finished article is tested
- OEKO-TEX MADE IN GREEN — product label that also verifies sustainable and socially responsible production facilities
- OEKO-TEX STEP — certification for production facilities, covering environmental performance, chemical management, and social responsibility
- OEKO-TEX LEATHER STANDARD — equivalent testing for leather goods
For sleepwear consumers, OEKO-TEX STANDARD 100 is the most directly relevant — product-level, independently tested, and applicable at every stage from yarn to finished product.
What Harmful Substances Does OEKO-TEX Screen For?
OEKO-TEX® STANDARD 100 tests textiles for a wide range of harmful substances. These fall into several broad categories:
Pesticide Residues
The STANDARD 100 limit values include pesticides, a consideration for natural fibers such as cotton.
Heavy Metals
The STANDARD 100 limit values include extractable heavy metals such as lead, cadmium, chromium and nickel.
Formaldehyde
Formaldehyde can be used to enhance wrinkle resistance in some clothing and textiles, according to the US Government Accountability Office. STANDARD 100 limits it: for baby articles it must not be detectable, and for articles with direct skin contact the limit is 75 mg/kg.
pH Value
A fabric's pH also matters for how it feels against skin. For articles with direct skin contact, STANDARD 100 sets a pH range of 4.0 to 7.5.
Allergenic Dyes and Other Chemical Finishes
This category includes certain dyes and chemical finishes that textile safety standards restrict.
The testing limits are not static. The OEKO-TEX® Association updates its criteria over time as science and regulations change.
Why Sleepwear Deserves a Closer Look
We spend a large part of our lives asleep, and sleepwear stays against the skin for hours at a time. That long, close contact is one reason many people pay attention to what their sleepwear is made of and how it was processed. If you have sensitive skin, independent certification is one more way to choose with confidence.
OEKO-TEX® STANDARD 100 applies its strictest limits to items made for babies and toddlers.
How OEKO-TEX and TENCEL™ Modal Work Together
TENCEL™ Modal, a fiber made by Lenzing from wood sourced from responsibly managed forests, is described by Lenzing as favoring fabric softness. Lenzing describes its production as highly resource-efficient, with high recovery rates of chemicals. Eberjey describes its TENCEL™ Modal as buttery soft and breathable.
Even so, a fiber with sustainable origins can be processed, dyed, or finished with chemicals that undermine its inherent gentleness. OEKO-TEX® STANDARD 100 testing addresses that side: certified articles are tested against a list of over 1,000 harmful substances, from yarn to finished product. Fiber sourcing is a separate question, which is where Lenzing's own claims for TENCEL™ Modal about responsibly managed forests come in.
Eberjey's Gisele TENCEL™ Modal Long PJ Set — the brand's iconic set, with more than 1,400 five-star reviews — is made from TENCEL™ Modal verified by OEKO-TEX® Standard 100.
How to Verify a Brand's OEKO-TEX Certification
OEKO-TEX® offers a public Label Check at oeko-tex.com. A STANDARD 100 label shows a test number and the responsible testing institute, and entering the label number lets you check that the label is official.
That is what sets it apart from a brand simply describing a product as "clean" or "natural". When evaluating any sleepwear brand's safety claims, one question cuts through the noise: Is there a certification number I can independently verify? Certificates must be renewed, so a valid label reflects current production practices — not a one-time historical test.
What to Look for When Shopping for Certified Sleepwear
Look for the Label, Not Just the Language
Words like "natural" and "clean" on their own do not tell you who tested what. OEKO-TEX® STANDARD 100 is an independent certification with a label number you can check.
Consider the Full Garment, Not Just the Fabric
OEKO-TEX tests every component of a finished garment — fabric, dyes, thread, elastic, closures. Where you can, look for certification that covers the whole article, not just one component.
Prioritize What's Worn Closest to Skin — and Longest
Sleepwear and intimates sit directly against the skin, and OEKO-TEX® sets its strictest requirements for articles for babies and children up to 3 years, which is worth knowing when shopping children's clothing. People with sensitive skin may especially appreciate certified textiles. Eberjey pieces like the Lara TENCEL™ Modal Slip, whose fabric and lace are verified by OEKO-TEX® Standard 100, apply this same logic to everyday wear.
Is OEKO-TEX the Same as Organic Certification?
No. Organic textile standards such as GOTS (Global Organic Textile Standard) require certified organic fibers and cover every step of production, from fiber processing and spinning to wet processing, manufacturing and trading, including chemical inputs and social criteria.
OEKO-TEX STANDARD 100 is a certification of the finished product — it tests what is actually present in the garment you wear, regardless of how the fiber was grown. A fabric from organic fiber can theoretically fail OEKO-TEX testing if harmful substances were introduced during dyeing or finishing; conversely, conventionally grown cotton can pass if residues fall within permissible limits. The two certifications are complementary rather than interchangeable.
The Quiet Assurance Behind the Label
OEKO-TEX certification answers a deceptively simple question: Has this textile been tested for harmful substances? It answers that question on the basis of independent laboratory testing, annual renewal, and a publicly verifiable certification database maintained by an independent international organization. In a textile market crowded with unverifiable "clean" and "natural" claims, that independent verification is worth something — especially for sleepwear that spends eight hours against your skin every night, night after night. The hours of sleep are hours of restoration. When Eberjey chooses fabrics verified by OEKO-TEX® Standard 100, the intention is the same as the intention behind every Gisele set, every softly tailored bralette, every carefully sourced thread: that what touches your skin should be worthy of the trust you place in it — and the rest you're working toward.
Frequently asked questions
What is OEKO-TEX certification?
OEKO-TEX® is an independent testing and labeling system for textiles. OEKO-TEX® STANDARD 100 means a finished textile has been tested for harmful substances, covering components like fabric, thread and dyes.
Why does OEKO-TEX certification matter for sleepwear?
Sleepwear sits against your skin for hours every night, so many people want to know how it was made and processed. OEKO-TEX® STANDARD 100 offers independent verification that the fabric has been tested for harmful substances, rather than relying on words like "clean" or "natural" alone.
Is OEKO-TEX certification the same as organic certification?
No. Organic standards such as GOTS require certified organic fibers and cover production from spinning to manufacturing. OEKO-TEX® STANDARD 100 tests articles for harmful substances, so the two are complementary rather than interchangeable.
How can I check that a product is OEKO-TEX certified?
Certified products carry a label number that you can enter in Label Check on the OEKO-TEX® website to confirm the label is official. If a brand makes a safety claim, a label number you can check is a good sign.
Are Eberjey's pajamas OEKO-TEX certified?
The Gisele TENCEL™ Modal Long PJ Set, the Henry TENCEL™ Modal Long PJ Set and the Kids TENCEL™ Modal Unisex Long PJ Set are verified by OEKO-TEX® Standard 100, meaning they're dyed with safe and non-toxic dyes. The Inez Washable Silk Long PJ Set is also verified by OEKO-TEX® Standard 100 and produced using bluesign®-certified processes.
Sources
- OEKO-TEX®, “OEKO-TEX® STANDARD 100”
- OEKO-TEX®, “Questions & Answers: STANDARD 100 by OEKO-TEX®” (PDF)
- OEKO-TEX®, “OEKO-TEX® MADE IN GREEN”
- OEKO-TEX®, “OEKO-TEX® Sustainable Textile and Leather Production (STeP)”
- OEKO-TEX®, “STANDARD 100 Limit Values and Individual Substances According to Appendices 4 & 5 (Edition 02.2025)” (PDF)
- U.S. Government Accountability Office, “Formaldehyde in Textiles (GAO-10-875)”
- OEKO-TEX®, “OEKO-TEX® Labelling Guide” (PDF)
- Global Organic Textile Standard (GOTS), “GOTS – How the system works”
