Materials & Testing
This page sets out what Kiri period underwear is made of, what we have had independently tested, and — just as importantly — what that testing did and did not cover. If you want the underlying report, ask us and we will send it.
What the fabric is
Our period underwear is built in four layers: an outer shell, a stain- and leak-blocking layer, an absorbent core, and a comfort barrier against the skin. The Daywear pair holds 50 ml; the Nightwear pair holds 75 ml.
There is no dioxin, no chlorine and no rayon anywhere in the construction.
Independent testing
In May 2023 we sent our Daywear (KJ101) and Nightwear (KJ103) period underwear to an independent third-party testing laboratory in Hong Kong. Report reference HKGH03001608. Both styles passed both tests requested.
| What was tested | Standard | Result | Limit |
|---|---|---|---|
| PFOA and its salts | EU POPs Regulation (EC) No. 2019/1021, as amended by 2020/784 | Below detection limit (<10 ppb) | 25 ppb |
| PFOA-related substances | As above | Below detection limit (<50 ppb) | 1,000 ppb |
| PBDE flame retardants (Tetra, Penta, Hexa, Hepta, Deca) | EU POPs Regulation (EC) No. 2019/1021, Annex I Part A | Below detection limit (<5 mg/kg) | 500 mg/kg |
“Below detection limit” means the laboratory found none at the lowest level its method can measure — not simply that we came in under the legal cap.
What the testing covered, and what it didn't
We would rather be precise here than vague, because vagueness is how people get misled.
The flame retardant test covered all seven components of the garment, including the inner waterproof sheet — the layer that makes period underwear leak-proof, and the one most people want to know about.
The PFOA test covered the body and lining fabrics — four components. It did not separately cover the inner waterproof sheet.
PFOA is one substance group within a much larger family. “PFAS” describes thousands of related chemicals. What we hold is a PFOA result under the EU POPs Regulation, not a broad PFAS screen. We are not going to call our underwear “PFAS-free” on the strength of a PFOA test, because those are not the same claim, and you deserve to know the difference.
The report covers two styles from 2023 production. It does not cover our bras or our daily antibacterial panties.
Why we publish this
Period underwear sits against your skin for hours at a time, and concern about what is in it is entirely reasonable. Our view is that a brand should be able to show you a document rather than a slogan.
Ask any brand — including us — for their testing documentation and material disclosures, then read what comes back and check what it actually covers. A brand that cannot produce anything has told you something.
Ask us for the report
Email hello@kirijourney.com and we will send the full report. If there is a specific substance you need us to test for, tell us — it is useful for us to know what customers are actually worried about.
More on how the layers work in our guide to how period underwear works, and on keeping them working in how to wash and care for period underwear.
