Plastic-Free Underwear & Undergarments

Underwear is the single best place to start with plastic-free clothing, for the same reasons a baby bottle beats a serving platter: contact time and contact area. It's worn all day, directly against the body's most absorptive and sensitive skin, often warm and damp with sweat - exactly the conditions that mobilize whatever chemistry a fabric carries. Most mainstream underwear is majority synthetic (polyester or nylon with elastane), which sheds microplastics and can hold dyes, anti-odor treatments, and PFAS-based finishes against the skin for hours. Leakproof/period underwear has drawn specific scrutiny after PFAS were found in several brands. Even "cotton" underwear almost always has an elastane or covered-synthetic waistband. Getting this one category right - natural fiber, minimal or natural-rubber elastic, clean finishing - is a bigger real-world win than any single outer garment.