An independent EPA-certified lab testing review finding Kudos diapers showed PFAS indications despite OEKO-TEX certification, while Hello Bello, Honest, Dyper, Abby & Finn, and Coterie tested clean.
By James T. Reilly · September 25, 2026
Part of the complete guide to diaper delivery subscriptions for multi-child and small-age-gap households.
Bottom line up front: An EPA-certified laboratory, commissioned by Mamavation in partnership with Environmental Health News and reviewed by four named PhD-level toxicologists, independently tested dozens of diaper brands for indications of PFAS ("forever chemicals") in 2023–2024. Of the six brands this cluster has covered, four tested clean — Hello Bello, Honest Company, Dyper, and Abby & Finn — and a fifth, Coterie, tested clean across two separate rounds of testing, including an expanded, more sensitive 40-analyte test in August 2024. Kudos did not test clean. Three of four Kudos diaper samples tested showed organic fluorine — a marker for PFAS — at levels ranging from 16 to 53 parts per million, despite carrying OEKO-TEX Standard 100 certification, a credential this cluster has repeatedly cited as a genuine third-party safety signal across the Kudos cotton-premium breakdown, the Kudos 2026 manufacturing investigation, the Honest vs. Kudos comparison, and the . This article documents exactly what that testing found, why OEKO-TEX certification didn't catch it, and what this means for every prior Kudos claim in this cluster.
Every materials comparison in this cluster so far — the topsheet-versus-topsheet comparisons in Articles 2, 3, 11, and 12 — has relied on what brands themselves publish about their own formulations, cross-referenced against named third-party certifications like OEKO-TEX Standard 100. That's a reasonable methodology as far as it goes, but it has a specific blind spot: a certification is only as good as what it actually tests for, and this section of this article's research uncovered a real, documented gap in exactly the certification this cluster has leaned on most heavily for Kudos and Dyper specifically.
The testing summarized in this article was conducted by an EPA-certified laboratory on behalf of Mamavation, a consumer-testing organization, in partnership with Environmental Health News, with scientific review from four named, credentialed toxicologists: Terrence Collins (Director of the Institute for Green Sciences at Carnegie Mellon University), Linda Birnbaum (former Director of the National Institute of Environmental Health Sciences and National Toxicology Program), Pete Myers (Chief Scientist at Environmental Health Sciences), and Scott Belcher (Associate Professor at the Center for Environmental & Health Effects of PFAS at North Carolina State University). This is independent, credentialed, methodologically documented testing — not a marketing claim from a competing brand, and not an anonymous internet allegation.
The lab tested for organic fluorine — a chemical marker present in all PFAS compounds — using Determination of Total Fluorine by Oxygen Flask Combustion and Ion-Selective Electrode, with results above a 10 parts-per-million (ppm) detection threshold flagged as indications of PFAS. Both the inside (skin-contact) and outside surfaces of each diaper were tested separately. Sixty-five diaper products from 40 brands were tested between February and August 2023, purchased directly by Mamavation or donated by community members, with results published starting in November 2023 and updated through August 2024. Mamavation's own stated limitation is worth repeating rather than glossing over: this was a "spot-check" of the industry, not an exhaustive or ongoing audit, and the organization explicitly states it "cannot make predictions about brands and products that we have not tested" — including, this article would add, products manufactured or reformulated after the testing window closed.
| Brand | Result | Category Assigned | Notes |
|---|---|---|---|
| Hello Bello (Premium Protection) | Non-detect, inside and outside | Better | ECF (not TCF) bleaching process |
| Honest Company (diapers and training pants) | Non-detect, inside and outside, both products tested | Better | ECF bleaching; per the testing notes, had recently switched from TCF to ECF as of the testing period |
| Dyper (Plant-Based Bamboo) | Non-detect, inside and outside, two samples tested | Better | ECF bleaching; OEKO-TEX certified |
| Abby & Finn | Non-detect, inside and outside | Best | TCF bleaching; polypropylene topsheet noted |
| Coterie | Non-detect, inside and outside; retested August 2024 across 40 PFAS analytes down to parts-per-trillion — again non-detect | Best | TCF bleaching; polypropylene topsheet noted |
| Kudos | Detected: Size 4 sample, 48 ppm inside / 53 ppm outside. Second Size 4 sample, 16 ppm inside / 19 ppm outside. Fourth sample tested, 18.5 ppm inside / 19 ppm outside. (One Size 5 sample tested non-detect.) | Not Our Favorite (PFAS detected) | OEKO-TEX certified — one of two OEKO-TEX-certified brands in the entire study that showed PFAS indications |
Three of four Kudos samples tested came back positive for organic fluorine, at levels ranging from roughly 1.6 to over 5 times the lab's 10 ppm detection threshold. Only the Size 5 sample tested clean. This is a mixed but genuinely concerning pattern — not a single anomalous result, but a repeated finding across multiple separately-tested diapers from the same brand.
This is the single most important explanatory finding in this article, because it directly affects how this cluster's readers should weigh OEKO-TEX certification going forward — a credential cited as a positive trust signal for both Kudos and Dyper throughout this series.
OEKO-TEX Standard 100 does test for PFAS in some of its certification tiers, but the specific method it mandates — Extractable Organic Fluorine (EOF) testing — has a documented technical blind spot: it does not extract PFAS polymers, including polytetrafluoroethylene (PTFE), the same family of chemical as the coating on non-stick cookware. Mamavation's reporting states plainly that this is not a hypothetical concern: "We found two perfect examples of this possibility in our testing when we found an indication of PFAS in diapers with OEKO-TEX certification" — and Kudos is one of the two brands referenced. Total organic fluorine testing, the method Mamavation's lab used, captures PTFE and other fluoropolymers that EOF testing misses, which is precisely why a product can be OEKO-TEX certified and still test positive under a more comprehensive testing method.
Terrence Collins of Carnegie Mellon, reviewing the study, added a second, independent critique of the same certification: even where OEKO-TEX's EOF method does apply, its Class 1 standard (the tier for baby products) currently allows up to 10 ppm of Extractable Organic Fluorine — a threshold Collins specifically called "too much, way too much" relative to current drinking-water PFAS safety standards. This means OEKO-TEX certification, as currently structured, cannot be read as a PFAS-free guarantee even on its own terms, independent of the PTFE testing gap. This is a direct, credentialed, scientifically-sourced correction to how this cluster has previously characterized that certification.
California's regulatory response is directly relevant here too. AB 652, effective July 1, 2023, prohibits intentionally added PFAS above specific thresholds in children's products sold in California, explicitly using total organic fluorine as the compliance standard — not extractable organic fluorine, precisely because the state recognized that EOF testing misses PTFE. A product could plausibly be OEKO-TEX certified and still fail to meet California's total-organic-fluorine-based standard, a regulatory tension Mamavation's reporting flags directly and this article is relaying accurately rather than independently verifying against California enforcement action, since no such enforcement action against any brand in this cluster was identified in this research.
The Coterie vs. Kudos comparison raised concerns about Coterie's plastic (polypropylene) topsheet, contrasting it against Kudos's cotton topsheet. This article's PFAS findings complicate that narrative in an important way, and there's a real legal history attached that deserves precise handling rather than a vague mention.
May 2024: A proposed class action, Saedi et al. v. Coterie Baby, Inc. (Case No. 24-cv-3893, U.S. District Court for the Southern District of New York), was filed, alleging Coterie deceptively marketed its diapers as "PFAS-free" or "below detectable levels" for perfluorinated compounds despite the products actually containing PFAS. The complaint reportedly argued that manufacturing a genuinely 100% PFAS-free diaper is essentially impossible given how ubiquitous PFAS chemicals have become in the environment and supply chain generally.
August 2024: Mamavation independently sent Coterie Size One diapers back to its lab for an expanded test — 40 specific PFAS analytes, tested down to parts-per-trillion sensitivity, a substantially more rigorous test than the organic-fluorine screening used in the original study. The result: non-detect across the board.
October 4, 2024: A federal judge dismissed the lawsuit. Critically, the dismissal was on standing grounds — the court found lead plaintiff Roz Saedi had not adequately alleged that the specific diapers she personally purchased actually contained PFAS, which is a pleading defect, not a substantive ruling on whether Coterie's products do or don't contain PFAS in general. This distinction matters and this article isn't going to blur it: a dismissal for lack of standing doesn't vindicate a company's underlying product claims, it means this particular plaintiff didn't plead her individual case adequately.
Ongoing tracking discrepancy worth flagging: Truth in Advertising (TINA.org), a consumer-advocacy litigation tracker, continued to list the case status as "Pending" across multiple pages of its site reviewed for this research, which doesn't fully reconcile with the October 2024 dismissal reported by Bloomberg Law and PFAS Central. This could reflect an amended complaint, an appeal, or simply a tracker page that hadn't been updated at the time of this research — this article could not resolve that discrepancy definitively and is reporting it as an open question rather than guessing at an explanation.
Putting the legal and lab findings together: Coterie was sued over PFAS claims, defeated that suit on procedural grounds (not a substantive vindication), and separately, through Mamavation's own independent lab testing — both the initial study and a more rigorous August 2024 follow-up — tested clean for PFAS. Two different forms of scrutiny, one legal and one scientific, and neither one found confirmed PFAS contamination in Coterie's product, even though the legal claim was never substantively resolved either way. This is a meaningfully different, more reassuring picture on the specific PFAS question than the plastic-topsheet finding in The Coterie vs. Kudos comparison might suggest on its own — the two findings (polypropylene topsheet, clean PFAS testing) aren't in conflict; a synthetic topsheet material and PFAS treatment are separate manufacturing choices, and Coterie's, per available evidence, doesn't appear to involve the latter.
The Kudos cotton-premium breakdown built a Contact Dermatitis Shield Analysis around Kudos's cotton topsheet specifically as a way of "keeping plastic and VOCs away from skin." The Kudos 2026 manufacturing investigation, the Honest vs. Kudos comparison, and the all cited Kudos's OEKO-TEX Standard 100 certification as a genuine third-party trust signal, including in direct comparisons against Honest and Coterie. This article's findings require a direct correction to that framing, not a footnote. A cotton topsheet avoiding the specific concern of plastic touching skin does not, based on this testing, mean the product avoids PFAS — the two are different chemical categories addressing different concerns, and Kudos's cotton-versus-plastic positioning, accurate as it is on its own narrow terms, was never a claim about PFAS specifically. This article isn't undoing the materials-composition findings in this cluster's earlier articles; it's adding a category of concern those articles didn't address, because until this research, this cluster hadn't gone looking for independent PFAS testing data at all.
One important caveat working in the opposite direction, for fairness: this testing was conducted in 2023–2024, on the pre-2026 Kudos product — the same version The Kudos 2026 manufacturing investigation documented as having undergone a reported manufacturing shift starting in March 2026. This article cannot tell you whether the current, redesigned Kudos diaper has the same, better, or worse PFAS profile than the version tested here. It's entirely possible a manufacturing change altered this specific characteristic in either direction, and no post-2026 independent PFAS testing of Kudos was located for this research. This is precisely the kind of claim this cluster has committed, from the Kudos 2026 manufacturing investigation onward, not to guess at — so this article won't.
Mamavation's own methodology notes a specific limitation worth repeating: the lab was not able to test the absorbent core pulp inside the diapers, only the inside and outside surfaces. This means the organic fluorine results reported throughout this article describe the topsheet and backsheet layers specifically, not the full diaper assembly including its internal absorbent core — a meaningful scope limitation for any reader assuming "tested clean" means the entire product, core included, was screened.
Separately, a reader comment on Mamavation's own published study, reviewed for this research, raised a specific, unresolved question about Healthy Baby — the brand Mamavation named its overall "top pick" — noting the brand's own website reportedly discloses its topsheet is plastic, not the organic cotton a shopper might assume, with only 15% organic cotton in the backsheet (which doesn't contact skin). Mamavation's team did not appear to have directly addressed that specific comment as of this research. This isn't a claim this article can independently verify, and Healthy Baby is outside this cluster's scope regardless — but it's included here as a useful reminder that even the most rigorous available source in this space is not beyond needing its own claims double-checked, which is the same standard this entire cluster has tried to hold every brand to.
This article has referenced PFAS as a health concern throughout without detailing why, and given this cluster's consistent practice of grounding claims rather than asserting them, that deserves its own treatment here. PFAS are a large class of synthetic chemicals used for decades for their water-, oil-, and stain-resistant properties — the same basic chemistry family behind non-stick cookware coatings and water-repellent fabric treatments. Linda Birnbaum, the former NIEHS/NTP director who reviewed the study this article summarizes, stated the concern plainly: "They accumulate inside the body and are close to impossible to get rid of. We already know that exposure to these chemicals can cause problems in pregnant women, but the effects on babies at this young age are mostly unknown. But just because we don't know all the health impacts doesn't mean they are safe."
The broader toxicological literature referenced in Mamavation's reporting associates PFAS exposure with a range of effects, summarized here as a general risk profile rather than a claim about any individual product or child: reduced immune function and vaccine response, disrupted growth and behavioral development in infants and children, endocrine and thyroid disruption, increased cholesterol, and — in longer-term population studies — associations with certain cancers and reduced fertility. Scott Belcher of NC State's PFAS research center specifically flagged that total organic fluorine testing, the method used in this study, is a legitimate way to "spot-check" for PFAS broadly, including fluoropolymers like PTFE that narrower single-compound tests would miss entirely.
Why this matters more for a diaper specifically than many other PFAS-adjacent products: the diaper area is in prolonged, direct, repeated contact with an infant's skin for the first two to three years of life, during a developmental window when — per Birnbaum's own caution above — the specific health effects of this kind of exposure in very young children remain under-researched rather than well-characterized. This isn't a basis for alarm calibrated to any specific outcome, since the research base on this specific exposure pathway in infants is, by the toxicologists' own account, incomplete. It is a basis for taking independent verification seriously rather than relying solely on a brand's own "non-toxic" or "clean" marketing language — which is the entire premise this article is built on.
This cluster's audience faces a version of this finding that a single-child household doesn't: repeated, compounded exposure across two or more children, often overlapping in time. A household running two simultaneous Kudos subscriptions — the twins-and-multiples scenario The twins and multiples subscription guide documented as requiring multiple full-price bundles rather than one combined order — is, per this article's findings, doubling exposure to a product that tested positive for PFAS in the majority of samples examined, not diversifying away from that exposure by using the same brand for both children. Conversely, a narrow-age-gap household using The Diaper Bundle Dashboard guide's two-size mixing approach with Hello Bello or Honest is, per this article's findings, mixing two sizes of a brand that tested clean rather than compounding risk across sizes.
This is a genuinely different risk calculus than the cost or convenience factors this cluster has otherwise emphasized, and it's worth stating plainly: for a household specifically prioritizing PFAS avoidance, the brand-selection stakes documented throughout this cluster's other eleven articles — cost, absorbency, subscription flexibility, materials philosophy — are all secondary to this article's findings. A cheaper, less flexible, less premium-positioned brand that tested clean is a better match for that specific priority than a more expensive, more flexibly-marketed brand that didn't.
Did Kudos diapers test positive for PFAS? Yes — three of four samples tested by an EPA-certified lab on behalf of Mamavation showed organic fluorine (a PFAS marker) between 16 and 53 ppm, above the 10 ppm detection threshold. One sample (Size 5) tested non-detect.
Does Kudos's OEKO-TEX certification mean it's PFAS-free? No. OEKO-TEX Standard 100's PFAS testing method (Extractable Organic Fluorine) doesn't extract PFAS polymers like PTFE, meaning a product can be certified and still contain PFAS that the certification's own testing wouldn't catch — which is exactly what this testing found for Kudos.
Did Coterie test positive for PFAS? No — Coterie tested non-detect in the original study and again in an expanded, more sensitive 40-analyte test conducted in August 2024, despite having a synthetic (polypropylene) topsheet, per The Coterie vs. Kudos comparison.
Was Coterie sued over PFAS claims? Yes — a proposed class action filed in May 2024 alleged deceptive PFAS-free marketing. It was dismissed in October 2024 on standing grounds (the plaintiff didn't adequately allege her specific diapers contained PFAS), which is a procedural outcome, not a substantive finding on the underlying PFAS question.
Did Hello Bello, Honest, Dyper, or Abby & Finn test positive for PFAS? No — all four tested non-detect for organic fluorine on both the inside and outside of the samples tested.
Is this testing current? No — testing was conducted between February 2023 and August 2024, with results published and updated through April 2024 (and the Coterie retest in August 2024). Formulations can change without notice, and this article cannot confirm whether any brand's current product matches what was tested.
Does this affect the 2026 Kudos manufacturing situation covered in The Kudos 2026 manufacturing investigation? Not directly — this testing predates the reported 2026 redesign. Whether the current, redesigned Kudos product has the same PFAS profile as the pre-2026 product tested here is unconfirmed in either direction.
What is organic fluorine, and why is it used as a PFAS marker? All PFAS chemicals are carbon-based compounds containing fluorine. Testing for total organic fluorine captures the presence of PFAS broadly, including specific compounds that narrower, single-chemical tests might miss — though it can also occasionally capture other fluorine-containing substances unrelated to PFAS, a limitation of the method worth knowing about.
Should I stop using Kudos based on this article? This article documents lab results and lets you weigh them; it's not making that decision for you. Given the explicit caveat that this data predates 2026 product changes, a reasonable next step for a current Kudos household concerned about this finding is contacting the company directly for current testing information, rather than assuming this 2023–2024 data describes today's product with certainty in either direction.
Were the diapers tested for anything besides PFAS? This specific study focused on organic fluorine as a PFAS marker. Mamavation's broader reporting, reviewed for this research, also discusses other categories of concern across the diaper industry generally — chlorine bleaching methods, VOCs, undisclosed fragrances, phthalates, and organotin compounds — though brand-specific results for those categories, beyond what's already documented elsewhere in this cluster, were outside this article's scope.
Is any brand in this cluster completely free of any chemical of concern? No brand tested achieved a completely clean bill across every category Mamavation's broader reporting examines — even brands with non-detect PFAS results were flagged for other considerations, like ECF (rather than TCF) chlorine processing for Hello Bello, Honest, and Dyper. This article's scope is specifically PFAS; readers wanting the fuller picture should consult Mamavation's original published study directly.
Does this article mean a twins or multiples household should avoid Kudos entirely? This article isn't making that determination for you, but it's a directly relevant data point for that decision: The twins and multiples subscription guide found no combined-bundle discount exists for same-size multiples on any of the five brands covered there, meaning a household running two or three simultaneous Kudos subscriptions is, per this article's findings, compounding exposure to a product with a documented PFAS detection pattern rather than mitigating it through brand diversification.
What should I do if I want to keep using Kudos despite this article's findings? Contact the company directly and ask specifically about current PFAS testing on the product as currently manufactured — this article's data is limited to 2023–2024 samples and cannot speak to anything about the product's current formulation, including whatever changes may or may not be connected to the 2026 manufacturing situation The Kudos 2026 manufacturing investigation documented.
This article summarizes independent laboratory testing and legal proceedings as reported by Mamavation, Environmental Health News, Bloomberg Law, PFAS Central, and Truth in Advertising, current as of this writing. This is not medical advice and not a substitute for consulting current, brand-direct information or a toxicologist regarding any specific health concern. Nothing in this article should be read as a legal conclusion about the Coterie litigation beyond what is documented above. Testing reflects specific samples at a specific point in time; product formulations change, and confirming current information directly with each brand is recommended before making a purchasing decision based on this article.
This cluster's related coverage: the Kudos cotton-premium breakdown and the Kudos 2026 manufacturing investigation cover Kudos's materials case and 2026 manufacturing situation in depth. the twins and multiples subscription guide introduced Abby & Finn to this cluster. the Coterie vs. Kudos comparison documents Coterie's confirmed polypropylene topsheet, a separate finding from this article's PFAS results.
More to read
Consumer Reports' June 2026 PFAS testing of 18 baby wipe brands, including Hello Bello, Honest, Dyper, and Coterie, all clean, with Kudos and Abby & Finn not included in the study.
Whether Kudos' 100% cotton-lined diaper subscription is worth its price premium for a two-child household.
An evidence-based investigation into reported 2026 manufacturing and quality changes to Kudos diapers, separating confirmed facts from unverified claims.
A direct, evidence-based comparison of Honest Company and Kudos diapers, including how Kudos's reported 2026 redesign may have narrowed its previously-verified performance edge.
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James Reilly is the father of Irish twins and writes Sibling Stack's guides from the inside — the gear that actually held up, the schedules that actually synced, and the stuff nobody warns you about when two kids are close enough in age that everything overlaps.
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