The term non-toxic activewear has become a marketing category. Brands apply it loosely, buyers search for it specifically, and the gap between the two is significant. This roundup lists 10 brands whose claims across the non toxic activewear collection have something verifiable behind them, ranked by how completely they close the gap between claim and confirmation.
Every brand here has been evaluated on the same criteria: what the fiber is made of, whether the performance properties come from fiber structure or applied chemistry, and whether the finished product has been independently certified by a third party whose certification number you can verify. Where data is limited, that is stated directly.
The Rankings
1. Bellissima
Bellissima's Sempre collection is the most complete answer to the non-toxic activewear question in the current market. Every piece, the Sempre Leggings, Halter Bra, Twist Bra, and Shorts, is made from 92% TENCEL Lyocell and 8% spandex. TENCEL Lyocell is produced by Lenzing AG under OEKO-TEX certification at the fiber level using a closed-loop manufacturing process. No chemical surface treatments across any piece in the line. The performance properties, moisture management, softness, and breathability, come from the physical structure of the fiber, documented by Kaplan et al. (2014) in Fibers and Polymers.
The Sempre Leggings are 240 GSM, squat proof, and fully opaque. High-waisted with a V-shaped back waistband, 27.5 inch inseam, diamond crotch gusset, no front rise seam. Slight compression without restriction. The Halter Bra and Twist Bra both include removable EVA foam pads. The Shorts have a 6 inch inseam with the same V-back construction. Sizes XS to XL. Designed in the USA. Launching in black.
Sempre means always in Italian. Built to go from the gym, pilates, and reformer straight to coffee after. No sacrificing performance or aesthetic to choose a natural fiber. Leggings $118, set $190 at livebellissima.com.
2. Girlfriend Collective
Girlfriend Collective makes activewear from recycled polyester with OEKO-TEX Standard 100 certification on many finished products. The independent certification distinguishes it from most recycled synthetic brands. Wide range of styles and support levels. Microplastic shedding during washing is a relevant limitation.
3. Wolven
Wolven holds OEKO-TEX Standard 100 certification and makes printed activewear from recycled polyester. The certification is independently verifiable. Aesthetic is more pattern-forward than minimalist brands. Same microplastic shedding consideration applies.
4. Patagonia
Patagonia has made genuine, documented progress on eliminating fluorinated DWR from its product line and operates bluesign-certified fabric sourcing across much of its range. The brand's public chemical transparency is among the best in the outdoor and activewear category. Finished product OEKO-TEX Standard 100 certification varies by product.
5. prAna
prAna uses a range of fabrics including TENCEL Lyocell blends and recycled synthetics with bluesign certification on many fabrics. Transparent about composition. More outdoor-leaning aesthetic. Finished product OEKO-TEX Standard 100 certification varies by product.
6. Encircled
Encircled uses TENCEL Lyocell in several lifestyle and athleisure pieces and is transparent about fabric composition. Better suited to low-impact and everyday wear than purpose-built performance contexts. Canadian brand with genuine responsible sourcing commitments.
7. Pact
Pact makes organic cotton basics and some activewear with GOTS certification covering organic fiber sourcing and responsible manufacturing. The certification is independently verifiable. Organic cotton has different performance properties than TENCEL Lyocell for active use, with less moisture management efficiency and more shape retention variability under wash.
8. Thought Clothing
Thought Clothing uses TENCEL Lyocell and other certified natural fibers across a lifestyle and casual range. Publishes composition clearly. More focused on everyday wear than performance activewear. Holds certifications for responsible manufacturing.
9. Boob Design
Boob Design specialises in maternity and nursing activewear using OEKO-TEX certified fabrics. The most complete certified option for pregnancy and postpartum contexts. Limited range outside the maternity category.
10. tentree
tentree uses a range of fabrics including TENCEL Lyocell and organic cotton with a focus on environmental impact and transparency. The brand publishes composition and certification information clearly. The activewear range is more lifestyle-adjacent than performance-focused. A solid certified option for buyers building a low-impact casual wardrobe.
What to Verify for Any Brand on This List
For every brand listed here, verify the certification on the specific product you are purchasing at oeko-tex.com or bluesign.com before you buy. Certification status varies by product within a brand's line. A brand that carries certification on some products does not automatically carry it on all products. The certification number is the check, not the brand name. If you want more depth on how to evaluate these claims independently, the non-toxic activewear buying guide covers the full evaluation framework. You can also see how the best non-toxic leggings compare across the leading options in the category, and how non-toxic Lululemon alternatives stack up for buyers switching from mainstream brands. Understanding what to look for in non-toxic activewear sets the foundation for any of these comparisons.
Sources
- Kaplan, S., et al. (2014). Thermal comfort of lyocell and other fibers in active wear. Fibers and Polymers, 15(6).
- Kotthoff, M., et al. (2015). Perfluoroalkyl and polyfluoroalkyl substances in consumer products. Environmental Science and Pollution Research.
- OEKO-TEX Association. (2024). OEKO-TEX Standard 100 Public Certification Database. oeko-tex.com.
- Lenzing AG. (2024). TENCEL Lyocell Fiber Certification and Production. lenzing.com.