Merino Short - 5"
Designed for everyday movement in merino.
Shop nowIs Recycled Polyester Safe? The Hidden BPA & Antimony Risk in 'Eco' Activewear
For the modern consumer, the "recycled" label on a pair of leggings feels like a win for the planet. We’ve been told that rPET (recycled polyethylene terephthalate), usually sourced from post-consumer plastic bottles, is the gold standard for sustainable fashion. However, emerging research from 2024 and 2025 is forcing a critical re-evaluation of this "green" assumption. While it may keep bottles out of the ocean, the chemical concentration that occurs during the recycling process is raising a terrifying question: is rPET safe to wear against your skin?
At Estroni, our mission is to challenge the industry’s reliance on plastics. We believe that chemicals and plastic are slowly degrading human health, and that true sustainability cannot exist without safety. When we look at the data surrounding recycled polyester toxicity, the "Green = Healthy" narrative quickly begins to dismantle.
The Recycling Paradox: Concentrating Toxins
The primary health concern with rPET lies in the mechanical and chemical recycling process. Plastic bottles were never intended to be worn as a "second skin" during high-intensity exercise. When these plastics are melted down and spun into new fibers, the chemicals used in the original plastic production don't just disappear—they often become more concentrated.
- BPA in recycled activewear: Bisphenol A (BPA) is a known endocrine disruptor. While virgin polyester contains trace amounts, recent testing by organizations like the Center for Environmental Health (CEH) found that recycled polyester blends often show significantly higher levels. This is frequently due to cross-contamination from bottle caps, labels, and adhesives that enter the recycling stream.
- Antimony Leaching in Clothing: Antimony trioxide is a catalyst used in the production of PET. Research indicates that recycled fibers can retain higher residual levels of this heavy metal. Unlike virgin fibers, the structural integrity of rPET can be lower, potentially increasing antimony leaching in clothing when exposed to the acidic environment of human sweat.
If you have ever wondered, Are My Gym Clothes Messing With My Hormones?, the answer may lie in these chemical residues that migrate from the fabric into your bloodstream as your pores open during a workout.
The "Sweat Factor": Why rPET is a Bioavailability Risk
Your skin is not a solid barrier; it is a semi-permeable organ. The conditions of a typical workout—increased body heat, friction, and moisture—create the perfect environment for chemical dermal absorption. When you wear "eco-friendly" synthetics, you aren't just wearing old water bottles; you are wearing a pressurized delivery system for plastic additives.
Data suggests that recycled vs virgin polyester health risks are most pronounced in activewear because of this "sweat leaching" effect. While a recycled polyester jacket might be low-risk, recycled leggings and sports bras sit directly against the most absorbent areas of the body. For those seeking >Workout Clothes Without Microplastics: What “Plastic-Free” Actually Means, the solution isn't just "recycling" the plastic—it is moving away from the synthetic fiber entirely.
Data Comparison: rPET vs. Virgin Polyester vs. Merino Wool
| Feature | Recycled Polyester (rPET) | Virgin Polyester | Merino Wool (95/5 Blend) |
|---|---|---|---|
| BPA Risk | High (due to contamination) | Moderate/Low | Zero (Natural Protein) |
| Heavy Metals | High (Antimony residues) | Moderate | Zero |
| Endocrine Safety | Challenged by 2024 studies | Low-Tox concerns | Bio-compatible |
| Microplastic Shedding | Very High | High | Zero (Biodegradable) |
The Merino Alternative: Safety by Nature
If the goal of "eco" activewear is to protect the planet and the person, Merino wool is the only material that truly delivers. Unlike synthetics that rely on chemical finishes for performance, Merino is naturally high-performance. It manages moisture at the vapor stage, preventing the bacteria-rich environment where odors thrive—meaning you don't need the toxic "anti-odor" silver treatments often found in recycled gear.
However, we recognize that 100% Merino has its limitations in a gym setting. Pure wool can lose its shape or develop holes under high friction. This is why we’ve developed a specific "Low-Tox" protocol. In our guide on 100% Merino vs 95/5 Blends: Which Is Better for Activewear?, we explain how adding a tiny 5% of elastane provides the structural reinforcement needed for leggings and bras without sacrificing the health benefits of the natural fiber.
Conclusion: Choosing Your Toxic Load
When asking is rPET safe to wear, the data increasingly suggests that the "recycled" label is more of a marketing victory than a health one. By choosing recycled polyester, you may be lowering your carbon footprint while simultaneously increasing your toxic load.
True everyday movement shouldn't require a chemical trade-off. By switching to Merino-rich activewear, you remove the risk of BPA, Antimony, and microplastic exposure, allowing your body to perform in a bio-compatible environment that supports your hormones rather than disrupting them.
