woman wearing period underwear

Period Underwear & Biocides: Everything You Need to Know

Period underwear has changed the game: comfy, sustainable, and so much easier than juggling pads or tampons. But when it comes to products that sit this close to your skin, you deserve to know exactly what’s inside them. One growing concern? Biocides.
So, what are they, why do some brands use them, and why should you think twice? Let’s break it down.

What Are Biocides and Why Are They in Period Underwear?

Biocides are basically chemicals (sometimes even metals like silver or zinc) that brands add to fabrics to fight bacteria, odor, or mold. The idea sounds nice, fresh underwear for longer, but here’s the catch:
  • The skin in your intimate area is super absorbent.
  • These chemicals can leach out and end up in your body.
  • Long-term effects? Still not fully understood.
Some studies even found high levels of silver in period underwear. Not exactly something you want near one of the most delicate ecosystems in your body.

Why Choose Biocide-Free?

Because your body already knows how to take care of itself. The vaginal microbiome is a carefully balanced system and throwing in antimicrobial agents can mess with it, causing irritation or even infections.
And it’s not just about you. Washing biocide-treated underwear releases chemicals like silver into the water system. Silver is toxic to aquatic life, which means your “freshness” hack might actually hurt the environment.
Here’s the kicker: biocides aren’t even necessary. With the right fabrics and regular washing, period underwear works just fine without them. Plenty of brands (including us) prove that performance, comfort, and leak protection don’t need chemical shortcuts.

What to Look for in Biocide-Free Period Underwear

When shopping, keep an eye out for:
  1. Materials
    • Organic cotton: breathable, natural, kind to your skin.
    • Bamboo: absorbent, naturally fresh without added chemicals.
    • Modal/Tencel: silky soft and moisture-wicking.
    • PUL (for leak protection): make sure it’s certified safe.
  2. Transparency & Certifications
    • Look for OEKO-TEX, GOTS, or similar certifications.
    • Brands that are open about their fabrics and processes are the ones you can trust.
  3. Absorbency & Design
    • Choose based on your flow—there are options from light to super-heavy.
    • Comfort and fit matter just as much as absorbency.
  4. Care Instructions
    • Rinse cold, wash gently, skip the harsh stuff like bleach or softener.
    • This keeps your undies working at their best (and chemical-free).
  5. Reputation
    • Check reviews. See what other people say about comfort, leaks, and brand values.

Our Top Biocide-Free Picks

Well.... all of them are, but why don't you try our discovery sets if you're new to the period underwear game.
Biocide-free period underwear isn’t just a trend, it’s a choice for your health and the planet. By ditching unnecessary chemicals, you protect your body’s natural balance, keep harmful substances out of waterways, and still enjoy reliable, comfortable, and stylish period protection.

Because when it comes to what you wear during your period, you shouldn’t have to compromise.

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