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Plastic-Free Rating
Feminine Care
Feminine Care·Thinx

Period Underwear (Bikini)

C
PFR Grade
Fair — some plastic content or limited transparency
Contains synthetic fibers (nylon, spandex) in the absorbent layers. More sustainable than disposables but contains plastic fibers.
PFR Reviewed

Period underwear with absorbent layers.

Score Breakdown

How scores are calculated

Materials (40%): How plastic-free the product is — raw materials, construction, and coatings.

Packaging (20%): Is the product packaged in plastic? Is it recyclable?

Transparency (20%): Does the brand disclose ingredients, sourcing, and manufacturing?

Durability (20%): How long does it last? Longer-lasting products reduce plastic waste over time.

Materials
5
Packaging
5
Transparency
7
Durability
8

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Last updated: April 20, 2026

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Moderate Exposure Risk — Why This Product Category Matters

Some synthetic or plastic components present. Use with awareness.

Why We Recommend This Product

Contains synthetic fibers (nylon, spandex) in the absorbent layers. More sustainable than disposables but contains plastic fibers.

Chemical & Health Analysis

Each chemical of concern is broken down below — what it is, where it comes from in this product, what it does to the body, and who is most at risk.

1

Plastic

Source

Health Risk

Possible plastic leaching

Who Is Most At Risk

All health claims are based on published, peer-reviewed research from the NIH, WHO, IARC, and peer-reviewed journals. This information is for educational purposes and does not constitute medical advice.

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