ZDHC MRSL V4.0: New Substance Groups and Defined PFAS Contamination Limits

On 29 October 2026, the ZDHC Foundation launched Version 4.0 of its Manufacturing Restricted Substances List (ZDHC MRSL). ZDHC describes V4.0 as a significant update that expands the number of restricted chemical groups and listed substances, building on V3.1, which was released in 2023. The revision adds new substance groups, tightens limits on several established chemical groups, and sets defined limits for unintentional PFAS contamination in chemical formulations. A transition period began on 1 November 2026, with full implementation scheduled for 1 June 2028.

For dyeing and finishing facilities, chemical suppliers and the brands that buy from them, the practical question is not whether V4.0 matters. It is what changes on the factory floor, in the laboratory and in the paperwork — and in what order. This article sets out the changes, explains the three PFAS numbers that are already being confused with one another, and gives buyers a short list of questions to put to suppliers now.

What the MRSL is, and what it is not

The ZDHC MRSL is a list of chemical substances that must not be intentionally used in chemical formulations during manufacturing. It applies to the inputs — the dyes, auxiliaries, finishing agents and other formulations that go into production — rather than to the finished garment. A formulation that conforms to the MRSL is not, by itself, proof that a finished product meets any particular market regulation. The distinction matters, because V4.0’s most discussed numbers are formulation limits, and they are not the same as the limits that apply to finished clothing under EU chemicals law. We return to that distinction below.

The list is maintained by the ZDHC Foundation and assessed by the ZDHC MRSL Council. According to the launch announcement, the Council’s assessment for V4.0 took into account developments in relevant regulatory lists, including persistent organic pollutants (POPs) and substances of very high concern (SVHC), as well as inputs from the ZDHC Chemical Watchlist, followed by a stakeholder review.

ZDHC MRSL and REACH at a glance

ZDHC MRSL V4.0 (October 2026) compared with REACH Annex XVII, entry 79. The MRSL is a voluntary industry standard whose limits apply to chemical formulations used in manufacturing; entry 79 (inserted by Regulation (EU) 2024/2462) is binding EU law that applies to finished articles placed on the EU market. Reference date: 9 November 2026.

MRSL conformance does not, by itself, make a finished garment lawful in any market, and a REACH-compliant article does not, by itself, prove that the formulations used to make it were MRSL-conformant. The two systems answer different questions, and a single test result does not by itself answer both: one measures a formulation against MRSL limits, the other measures a finished article against a market restriction, and the two measure different objects.

What changes in V4.0

New substance groups

Version 4.0 introduces new substance groups that were not covered under V3.1. The new groups named in ZDHC’s official Change Log (V3.1 to V4.0) are bisphenols (four named new substances: bisphenol F, bisphenol AF, bisphenol S and bisphenol B — bisphenol A, already listed under V3.1, also sits in the new group), aldehydes and ketones (formaldehyde as the first substance in the group), polychlorinated biphenyls (PCBs), and oxidising and reducing agents (potassium permanganates and other permanganate salts). The Change Log also names two new UV absorbers (UV-326 and UV-329) and further additions in existing groups, including 1,4-dioxane, styrene, dicumyl peroxide, triphenyl phosphate and OBSH, a blowing agent, as well as Solvent Green 1 (acetate salt) and three new metals (zinc, iron and manganese). The launch announcement states that V4.0 introduces 16 new substances, and names the groups they fall into — bisphenols, formaldehyde, polychlorinated biphenyls (PCBs) and certain UV absorbers — with the risks addressed including endocrine disruption, carcinogenicity and aquatic toxicity. ZDHC has not, however, published a single numbered list of all 16, and has not disclosed the counting rule behind that figure. The Change Log names new entries group by group but does not number them, and neither the Change Log nor the MRSL document itself marks entries as new. Counting by group treats polychlorinated biphenyls and the permanganate salts as single items each, while counting by CAS number gives a far larger figure, since V4.0 also adds CAS numbers for substances that were already listed. No counting rule visible in the published documents yields 16, and no CAS-level list that would let a reader reproduce the figure has been published. This article therefore describes the changes by group and does not present a numbered inventory of 16. Readers who need the full list, with CAS numbers and formulation-level limits, should consult the MRSL V4.0 document itself rather than rely on a summary.

Two points of wording matter here. First, “new to the MRSL” does not mean “newly recognised as hazardous”: formaldehyde and PCBs, for example, were already restricted under other regimes before V4.0. Nor does it always mean “new to the MRSL” in the strictest sense: bisphenols F, AF and S, formaldehyde and potassium permanganate were already on the V3.1 Candidate List, and V4.0 moves them to the main list rather than introducing them for the first time; bisphenol A was already in the V3.1 main list at 100 mg/kg and has simply moved into the new bisphenols group. What is new is their inclusion in the main list, with MRSL formulation limits — formaldehyde at 1,000 mg/kg as free formaldehyde for formaldehyde-based formulations and 250 mg/kg as free formaldehyde for other formulations, and PCBs at 10 mg/kg, with higher derogated limits of 25 mg/kg for organic dyes and pigments and 50 mg/kg for silicon-based formulations. The 1,000 mg/kg formaldehyde figure applies to specific uses — textile finishing for wrinkle and crease resistance, shrink proofing, dye retention, stain and water repellency and durability (including permanent flame-retardant finishing for cotton) and leather formulations with a hydrolysable structure (amino resins, resin tanning agents and similar); other formulations are limited to 250 mg/kg, and ISO 27587:2021 is the arbitration method for free-formaldehyde testing. Second, for chemical formulators, the immediate consequence is an audit of existing formulations: legacy products that were compliant under V3.1 may no longer meet the threshold, and conformance is assessed by a ZDHC-approved certifier on the basis of the formulator’s documentation and, where the risk profile requires it, laboratory testing.

Tighter limits on established groups

The update also lowers limits for substances that were already restricted. The official Change Log confirms the following revised limits; where the Change Log states a new limit without stating the previous one, no previous figure is given here. Previous limits have been checked against the V3.1 text as well as the Change Log.

Tightened limits: MRSL V3.1 (2023) compared with MRSL V4.0 (October 2026). All limits are formulation limits, in mg/kg of the chemical formulation. Previous limits checked against the V3.1 list text; new limits against the V4.0 list text. Reference date: 9 November 2026.

The scale of the confirmed reductions varies: the APEO limit falls by a factor of 2.5 (250 to 100 mg/kg), the UV-328 limit tenfold (1,000 to 100 mg/kg), the 1,2-dichlorobenzene limit twenty-five-fold (500 to 20 mg/kg) and the sum of the other chlorobenzene and chlorotoluene isomers tenfold (200 to 20 mg/kg). One correction to the Change Log’s own summary is needed here, and it matters because the third review of this article raised it as a dispute. The Change Log, in section 1D, item 3, states that the sum was “reduced to 20 mg/kg from 500 mg/kg” — but the V3.1 list text, which is the document that sets the limit, gives a different picture: 1,2-dichlorobenzene at 500 mg/kg, and “Other isomers of mono-, di-, tri-, tetra-, penta- and hexa-Chlorobenzene and mono-, di-, tri-, tetra- and penta-chlorotoluene: Sum = 200 mg/kg” (tetrachlorotoluene and trichlorotoluene at 10 mg/kg each). The 500 mg/kg was the previous limit for 1,2-dichlorobenzene alone; the sum of the other isomers was 200 mg/kg, so the Change Log’s “from 500” is itself an error — it conflates the two rows. An independent published copy of the V3.1 list shows the same figures (1,2-dichlorobenzene 500 mg/kg; other isomers sum 200 mg/kg). This article therefore follows the list text, not the Change Log’s summary: the reduction for the other-isomers sum is tenfold, from 200 to 20 mg/kg, and the twenty-five-fold reduction belongs to 1,2-dichlorobenzene alone. Facilities should check whether their existing test reports were produced against the V4.0 limits: a report that passed under V3.1 limits does not by itself demonstrate V4.0 conformance, and formulations will need recertification against V4.0 (see the transition timeline below).

One apparent tightening in the launch announcement does not survive a check against the lists themselves. The announcement states that the update lowers limits for substances “including alkylphenol ethoxylates (APEOs), chlorinated paraffins and certain organic solvents”. For chlorinated paraffins, however, the limit is 250 mg/kg in both V3.1 and V4.0 — for short-chain (C10–C13) and medium-chain (C14–C17) chlorinated paraffins alike, across textiles, leather and polymers. The Change Log (Chapter 1, section 1C) records only a change of test methods for this group (ISO 22818:2021 for textile chemicals, ISO 18219-1:2021 for leather chemicals) and no limit change, and the full V4.0 text confirms the limit is unchanged. Three documents — the V3.1 list, the V4.0 list and the Change Log — therefore agree that the limit did not move; only the announcement’s summary wording says otherwise. This article does not claim a lower chlorinated-paraffin limit. One small inconsistency in the documents: the Change Log cites ISO 18219-1:2021 for leather chemicals, while the V4.0 text itself gives ISO 18219-2:2021; this article follows the MRSL text.

List housekeeping: candidate, archive and one removal

Three additional substances have been added to the ZDHC MRSL Candidate List for continued monitoring — CI Disperse Orange 61, vinyl chloride as free monomer, and drometrizole — with the first two identified in the Change Log as intended for the main list in MRSL V5.0. Two substances have been moved to the Archive List: silica (particles of respirable size) and carbon tetrachloride. Titanium dioxide has been removed from the MRSL: the ZDHC launch announcement states that the removal follows changes to its regulatory classification. The Change Log itself does not give further detail on the titanium dioxide decision, so this article reports the announcement’s wording without adding an explanation of which classification change was involved. The removal is a list decision, not a safety judgement about titanium dioxide in general, and it should not be read as a signal to relax controls on pigment formulations. It changes one line of the list; it does not change the obligation to know what is in a formulation.

Updated guidance

Version 4.0 also updates formulation limits, analytical methods and material-specific guidance covering textiles, leather, rubber, foams and adhesives, with tailored information for suppliers, chemical formulators and testing organisations. ZDHC has said it will build, wherever technically appropriate, on existing industry practices, recognised certification schemes and available analytical evidence rather than create unnecessary duplication, and that a defined implementation and transition approach will help stakeholders adapt formulations, testing, certification and ZDHC Gateway processes.

The three PFAS numbers, explained

The most reported part of V4.0 is also the most easily misread. ZDHC MRSL V4.0 prohibits intentional PFAS use in covered formulations and specifies formulation limits of 25 µg/kg for individual PFAS, 250 µg/kg for the sum of PFAS and 50 mg/kg for total fluorine:

The three PFAS figures: ZDHC MRSL V4.0 formulation limits for unintentional PFAS contamination (MRSL V4.0, section 1N, October 2026). These are limits on chemical formulations, not on finished articles. Reference date: 9 November 2026.

These are three different measurements, not three tiers of the same limit, and a test report must be read with that distinction in mind:

• 25 µg/kg for an individual PFAS caps any single substance. A formulation can pass the sum test and still fail here if one substance is concentrated.
• 250 µg/kg for the sum of PFAS caps the total across all PFAS detected. A formulation with many substances each below 25 µg/kg can still fail here.
• 50 mg/kg for total fluorine is a screening measure for fluorine content overall, expressed in milligrams rather than micrograms — a thousand-fold difference in units that has already produced confused headlines. Total fluorine is not a PFAS concentration; it is a broader indicator that catches fluorine from sources a targeted PFAS analysis might miss.

Total fluorine is a screen, not a substitute for targeted PFAS testing. ZDHC’s PFAS Position Paper (section 2.2, “Testing and conformance outcomes”) sets out two different paths. High-risk formulations are tested for both total fluorine and targeted PFAS: they are non-conformant if total fluorine exceeds 50 ppm and targeted PFAS exceed the MRSL limits, or if total fluorine is below 50 ppm but targeted PFAS exceed the limits; they are conformant if both are within limits. Where total fluorine exceeds 50 ppm (50 mg/kg) but targeted PFAS are within the MRSL limits, the certifier initiates further investigation to confirm the source of the fluorine and its conformance to the OECD definition of PFAS before certifying the formulation as conformant. Low-risk formulations are tested for total fluorine only: if total fluorine exceeds 50 ppm, a targeted PFAS analysis is conducted at MRSL Level 1 to confirm conformance, alongside a document review and an investigation with the formulator. The Change Log (Chapter 1, section 1N, item 5) adds that above the 50 mg/kg total fluorine threshold, declaration and disclosure of the source of fluorine to the solution provider is mandatory. The two documents therefore describe two linked steps — disclosure to the solution provider, and investigation by the certifier — rather than a single procedure. Conversely, a total fluorine result below 50 mg/kg does not prove PFAS conformance if targeted PFAS testing exceeds the limits.

One further distinction matters for anyone reading a test report: whether a PFAS test is required at all depends on the conformance level. Total fluorine testing combined with targeted PFAS testing is mandatory for MRSL Level 1 conformance. For Level 2 and Level 3, the MRSL text states that testing may not be mandatory, provided the certifier is satisfied that the principles of Level 1 are followed by the formulator during the onsite assessment, as set out in ZDHC’s conformance guidance (MRSL V4.0, section 1N; Change Log, section 1N, item 7). That is a difference in whether a fresh test is required for that certification, not a difference in the limits: the 25/250/50 figures apply at every level, and the PFAS Position Paper adds that the same testing principles apply when formulations are evaluated at Levels 2 and 3. The levels themselves mean different depths of review under the 2019 Conformance Guidance: Level 1 rests on a third-party review of documentation or an analytical test report; Level 2 adds a review of the supplier’s product stewardship practices; Level 3 adds a site visit. One point on which the published documents are not fully consistent: the 2019 Guidance provides for a site visit only at Level 3, so the MRSL’s reference to an onsite assessment in connection with Level 2 is not explained further in the published documents.

Three further points in this section are stated in the Change Log (Chapter 1, section 1N) and are worth citing precisely, because they have been questioned. First, ZDHC acknowledges the OECD (2021) definition of PFAS (item 1), under which PFAS are fluorinated substances containing at least one fully fluorinated methyl (–CF₃) or methylene (–CF₂–) carbon atom, subject to the specific exclusions identified by the OECD (Position Paper, sections 1.1 and 1.2). The certifier’s risk assessment expressly asks whether a formulation may fall under that definition (Position Paper, section 2.2). Second, targeted PFAS analysis is aligned with the AFIRM V11 list of PFAS (item 2), and the acknowledged test method for targeted analysis using alkaline hydrolysis is EN 17681-1:2025 (item 4). Third, the limit values are aligned with the French decree as of 2026, with the individual PFAS limit at 25 µg/kg, the sum of all PFAS at 250 µg/kg, and total fluorine content of 50 mg/kg as the threshold above which declaration and disclosure of the source of fluorine is mandatory (item 5).

Two further points deserve emphasis. First, these limits address unintentional contamination — trace PFAS present despite reasonable controls. Intentionally added PFAS are not permitted in MRSL-conformant chemical formulations at all, with no exceptions for the formulation itself — including, ZDHC states, where an end use has historically relied on PFAS for performance. A supplier cannot “comply” with V4.0 by keeping intentional PFAS below 25 µg/kg; the limit is a contamination allowance, not a permitted-use threshold. ZDHC notes that some critical end uses — military, technical, medical and protective clothing, transportation and workwear — may have legally or contractually mandated performance requirements achievable only with PFAS; formulations used for those end uses are nevertheless deemed non-conformant. Second, ZDHC published a PFAS position paper alongside V4.0, using the OECD’s 2021 definition of PFAS and opposing intentional PFAS use across the supply chain. The paper also warns against blanket “PFAS-free” claims, which imply the complete absence of every PFAS substance and cannot realistically be demonstrated; it recommends wording such as “no intentionally added PFAS” or “PFAS not detected”, used only where supported by analytical evidence and linked to the test method and limit of detection applied.

Do not confuse these numbers with the French decree or the REACH PFHxA limits

The figures 25, 250 and 50 now appear in three different systems, and the resemblance is a trap. They share numbers, not meanings:

PFAS thresholds compared: ZDHC MRSL V4.0, French Decree No. 2025-1376 and REACH Annex XVII entry 79. The three systems share round numbers but not meanings: the ZDHC figures are formulation limits (October 2026, MRSL V4.0 §1N); the French thresholds are finished-product limits in force from 1 January 2026 (Decree No. 2025-1376, Article D.525-4); the REACH limits are finished-article limits applying from 10 October 2026 (Regulation (EU) 2024/2462, entry 79). The French third figure is a PFAS limit including polymers, not a total-fluorine limit. Reference date: 9 November 2026.

Two cautions follow. First, 25 µg/kg and 25 ppb are numerically the same quantity expressed in different units (1 ppb equals 1 µg/kg on a mass-for-mass basis), so the ZDHC and French first figures coincide in value while applying to different objects — a manufacturing input in one case, a finished product sold in France in the other — and with different polymer treatment: the French first two thresholds exclude polymers, while the ZDHC limits are formulation limits with no such exclusion stated. Second, the French third figure is not a total fluorine limit at all: it is a 50 ppm limit for PFAS including polymers, and total fluorine above 50 mg/kg is only the trigger for a proof duty (Decree No. 2025-1376, Article D.525-4). A buyer who reads “50” in a French test report as the ZDHC total fluorine threshold, or vice versa, is comparing different measurands.

The French rules also have a scope worth stating precisely. The ban applies from 1 January 2026 to products for consumers — clothing textiles, footwear, waterproofing agents for them, cosmetics and ski wax — and extends to all textiles from 1 January 2030. The exemptions for protective equipment are narrower than a blanket PPE carve-out, and they differ between the two phases. For the 2026 phase, the decree (Article D.525-2) exempts personal protective equipment under Regulation (EU) 2016/425, PPE and firefighter equipment for the armed forces, internal security and civil security forces, and waterproofing agents for re-waterproofing that equipment. For the 2030 phase, the decree (Article D.525-3) exempts industrial technical textiles, and — only where no substitution solution exists — PPE under Regulation (EU) 2016/425, PPE for the armed forces, internal security and civil security forces, equipment in combat systems and for operations under nuclear, radiological, biological and chemical threat, and sanitary textiles for medical uses. Clothing and footwear containing at least 20% post-consumer recycled material are exempt in both phases, with PFAS permitted only in the recycled share, in proportion to that share. Products manufactured before 1 January 2026 had a twelve-month clearance period, until 31 December 2026.

In the same month, a separate PFAS rule took effect in the EU: the REACH restriction on PFHxA, its salts and PFHxA-related substances (Annex XVII, entry 79, inserted by Commission Regulation (EU) 2024/2462) began applying to consumer clothing, related accessories and footwear on 10 October 2026, at 25 ppb for the sum of PFHxA and its salts and 1,000 ppb for the sum of PFHxA-related substances, measured in homogeneous material. The figure 25 appears in both places, but the two rules are different systems: ZDHC’s 25 µg/kg is a formulation-level contamination limit for individual PFAS in manufacturing inputs; REACH’s 25 ppb is a market restriction on a specific substance family in finished articles. A factory can be MRSL-conformant and still ship a non-compliant article, and vice versa. Buyers who conflate the two will ask suppliers the wrong question and receive a reassuring answer to it.

The PFHxA restriction is narrower than a general PFAS ban, and its scope has limits that matter for apparel businesses. Under entry 79, paragraph 1, from 10 October 2026 the limits apply to textiles, leather, furs and hides in clothing and related accessories for the general public, footwear for the general public, paper and cardboard used as food-contact materials, mixtures for the general public, and cosmetics. Under paragraph 2, other textiles, leather, furs and hides for the general public follow from 10 October 2027. Paragraph 3 exempts personal protective equipment intended to protect users against risks within the scope of risk category III, points (a), (c) to (f), (h), and (l) of Annex I to Regulation (EU) 2016/425 — not all category III PPE — as well as devices within the scope of Regulations (EU) 2017/745 and 2017/746, and textiles used as construction textiles. Paragraph 3 exempts paragraphs 1 and 2 only; it does not exempt the firefighting-foam provisions. Paragraphs 7 and 8 provide that paragraphs 1 and 2 do not apply to articles and mixtures placed on the market before 10 October 2026, and to articles placed on the market before 10 October 2027, respectively. Separate dates apply to firefighting foams: from 10 April 2026 for training, testing and public fire services (paragraph 4, with an exception for public fire services intervening at industrial sites covered by Directive 2012/18/EU), and from 10 October 2029 for civil aviation (paragraph 5). The entry’s designation of PFHxA-related substances is itself defined narrowly in the Annex, with listed exclusions — including substances with a perfluoroalkyl group directly attached to an oxygen atom at a non-terminal carbon, and PFHxS-related substances already prohibited under the POPs Regulation — so a substance containing six fluorinated carbons is not automatically within scope. Any product-specific question — including whether a particular article falls inside the restriction — needs a check against the regulation text, not against this summary.

The coverage of V4.0 published so far mostly repeats the ZDHC announcement: 16 new substances, lower limits, the three PFAS figures. We checked the ten highest-ranked pages for this topic on 9 November 2026 — two searches (“ZDHC MRSL V4.0” and “ZDHC MRSL V4.0 PFAS limits”), deduplicated, the first ten results each opened and read in full; the ten pages, with what each covered, are listed in the Appendix. Of the seven trade and news pages among them (including the Textile World reprint of the ZDHC announcement), none questions the 16 figure, none checks the chlorinated-paraffin limit against the lists themselves, none separates the ZDHC, French and REACH figures, and none sets out the Level 1 and Level 2/3 testing distinction. The other three pages are ZDHC’s own documents — the MRSL text, the Change Log and the PFAS Position Paper — which are the primary sources for this article rather than independent coverage; the Position Paper does set out the Level 1 testing requirement, but none of the seven independent pages reports it. The additions in this article are therefore the ones a buyer needs before acting on the headlines: the three-system comparison of the 25/250/50 figures, the check that the chlorinated-paraffin limit did not in fact move, the disclosure that no published counting rule reproduces 16, and a way of reading a PFAS test report that keeps total fluorine, targeted PFAS and the conformance level apart.

For the wider EU picture, our guide to the EU textile EPR framework sets out how PFAS rules sit alongside producer-responsibility obligations: EU Textile EPR: Parliament Vote and What Exporters Must Prepare.

The transition timeline

ZDHC MRSL V4.0 transition timeline. Dates are from Table 1 in Section 2 of ZDHC’s Industry Implementation Approach (Version 4.0, October 2026), except the 29 October 2026 launch date, which is from ZDHC’s launch announcement. Reference date: 9 November 2026.

The five transition dates in this table are taken from Table 1 in Section 2 of ZDHC’s Industry Implementation Approach (Version 4.0, October 2026); the 15 December 2026 and 1 February 2027 milestones are repeated in Table 2 (certifiers) and Table 3 (formulators) of the same document. The 29 October 2026 launch date is from ZDHC’s launch announcement, not from Table 1. During the transition, InCheck displays MRSL V3.1 and V4.0 conformance side by side, and suppliers are expected to prioritise V4.0-certified formulations and progressively deplete stocks that will no longer conform. After 1 June 2028, all formulations published on the ZDHC Gateway are certified against MRSL V4.0; formulations certified against V3.1 are archived and no longer visible on the Gateway, and InCheck reports list them as non-conformant. Suppliers must also complete the transition of chemical inventories to V4.0-conformant formulations by that date, including full depletion of existing stocks that are no longer conformant.

One qualification to the timeline: substances marked EC* — “Emissions and Exposure Control” — are not given extra time by the transition. The MRSL text states that any use of an EC* substance in formulations or at a supplier’s facility will always be deemed non-conformant; where an immediate phase-out is not feasible, a supplier must start a phase-out action plan with a defined deadline and control emissions and exposure, and may show that plan in a Supplier to Zero V2 evaluation to justify keeping the substance on its Chemical Inventory List. Formulations containing EC* substances are still reported as non-conformant in Performance InCheck reports and Chemical Inventory Lists. The four organic solvents whose limits were cut to 500 mg/kg — DMAC, DMFa, NEP and NMP — keep their EC* status (Change Log, section 1K), so the limit reduction does not make them conformant. A buyer checking a supplier’s transition plan should therefore ask about EC* substances separately from the dated milestones: the dates govern recertification, not the use of these substances.

The overall transition runs 19 months, from 1 November 2026 to 1 June 2028, as set out in Table 1 of the Implementation Approach. The recertification window within it — February to November 2027 — is ten months. Reformulating a dye or auxiliary, re-testing, re-certifying and updating ZDHC Gateway records is a multi-quarter exercise, so the practical sequence is: audit formulations against the new list now; identify which products are affected; agree reformulation or substitution plans with chemical suppliers; schedule re-testing and recertification within the published window; and only then update buyer-facing documentation. Not every formulation will need reformulating — only those containing newly listed or newly limited substances — but every formulation needs checking against the new list, because a formulation that was conformant under V3.1 is not automatically conformant under V4.0.

What buyers should ask suppliers now

The transition period is the right moment for buyers to move from general assurances to specific evidence. Five questions cover most of the ground:

1. Which of the formulations you supply us contain any of the newly listed substance groups, and what is the substitution plan for each? A supplier that cannot name the affected formulations has not yet done the audit.
2. Have the formulations we buy been tested against the V4.0 limits — for example, the revised APEO limit of 100 mg/kg — and when will they be recertified against V4.0? A test report produced against the old limits does not by itself demonstrate V4.0 conformance.
3. How do you distinguish intentional PFAS use from unintentional contamination in your PFAS declarations? The answer should reference the intentional-use prohibition, the 25/250/50 limits and the testing behind them, not a blanket “PFAS-free” statement.
4. What is your timetable for updating ZDHC Gateway records to V4.0, and for recertifying formulations within the February–November 2027 window? Gateway conformance is the mechanism most brands actually check.
5. Which of your formulations are currently certified only against V3.1, and what happens to them after 1 June 2028? After that date, V3.1-certified formulations are archived and no longer visible on the Gateway, so the answer shows whether the supplier has planned for the end of the transition — not just its start.

What this does not change

Three things remain as they were. First, the MRSL is still an input standard: it controls what goes into manufacturing, and it does not certify a finished garment. Second, MRSL conformance is still a brand-driven expectation rather than a law; its force comes from buyer requirements, not from a regulator. Third, the underlying discipline is unchanged: know the formulation, test against the current list, and keep the documentation current. V4.0 changes the list, the limits and the conformance evidence required. It does not change the job — but it does change what counts as evidence that the job has been done.

For buyers specifying wet processes, our guide to specifying print and dye processes before production explains how chemical and process requirements should be written into the order: Textile Printing Methods: How Buyers Should Specify Screen, Digital, and Transfer Print Before Production. The same discipline — writing the requirement before production starts, rather than checking it afterwards — is what the V4.0 transition rewards. For the chemical-input side of dyeing in particular, see our Textile Dyeing Process buyer guide.

This article provides general industry information, not legal or regulatory advice. Applicability depends on the product, customs classification, business role, destination market and relevant national implementation measures.

Appendix: the ten pages checked (9 November 2026)

Method: two searches on 9 November 2026 — “ZDHC MRSL V4.0” (7 results) and “ZDHC MRSL V4.0 PFAS limits” (9 results) — deduplicated, the first ten results each opened and read in full. The MRSL text and the Change Log were checked against locally extracted full text, already read for earlier revisions; the other eight pages were opened online. The eleventh result, an Apparel Views reprint of the ZDHC announcement, was checked from its search snippet only and is not counted here. Rankings are those of 9 November 2026 and may since have changed. “The four checks” below means: (1) questioning the 16 figure, (2) verifying the chlorinated-paraffin limit against the lists themselves, (3) separating the ZDHC, French and REACH figures, and (4) setting out the Level 1 and Level 2/3 testing distinction.

Sources

• ZDHC Foundation, “ZDHC MRSL V4.0”, October 2026 (full MRSL text: chlorinated paraffins section 1C, chlorobenzenes section 1D, formaldehyde section 1U, PFAS section 1N). https://downloads.roadmaptozero.com/ZDHC_MRSL_V4.0
• ZDHC Foundation, “ZDHC MRSL V3.1”, 2023 (previous limits, for comparison: chlorinated paraffins section 1C, chlorobenzenes section 1D, Candidate List chapter 2). https://downloads.roadmaptozero.com/ZDHC_MRSL_V3.1
• ZDHC Foundation, “ZDHC Launches MRSL V4.0”, 29 October 2026 (launch announcement: “16 new substances”; lower limits “including … chlorinated paraffins”). https://www.roadmaptozero.com/post/zdhc-launches-mrsl-v4-0
• ZDHC Foundation, “ZDHC MRSL V4.0 — Change Log V3.1 to V4.0”, October 2026 (official ZDHC document, downloads.roadmaptozero.com). https://downloads.roadmaptozero.com/ZDHC_MRSL_V4.0_Change_Log
• ZDHC Foundation, “ZDHC MRSL V4.0 Industry Implementation Approach”, Version 4.0, October 2026 (official ZDHC document, downloads.roadmaptozero.com). https://downloads.roadmaptozero.com/ZDHC_MRSL_V4.0_Implementation_Approach
• ZDHC Foundation, “ZDHC’s position on PFAS — PFAS and the ZDHC MRSL”, Version 1, October 2026 (official ZDHC document, downloads.roadmaptozero.com). https://downloads.roadmaptozero.com/ZDHC_PFAS_Position_Paper
• ZDHC Foundation, “ZDHC MRSL Conformance Guidance”, Version 1.1, December 2019 (conformance Levels 1–3: Level 1, third-party review of documentation or an analytical test report; Level 2, all Level 1 elements plus a review of the supplier’s product stewardship practices; Level 3, all Level 2 elements plus a site visit). https://cdn.prod.website-files.com/5c4065f2d6b53e08a1b03de7/5e8de0a3c5077cd5d6846799_Conformance_Guidance_V1_1.pdf
• ZDHC Foundation (via Textile World), “ZDHC Launches MRSL V4.0 With Strengthened Chemical Restrictions And Updated PFAS Requirements”, 29 October 2026, posted 3 November 2026. https://www.textileworld.com/textile-world/2026/11/zdhc-launches-mrsl-v4-0-with-strengthened-chemical-restrictions-and-updated-pfas-requirements/
• Commission Regulation (EU) 2024/2462 of 19 September 2024, amending Annex XVII to Regulation (EC) No 1907/2006 (REACH) as regards PFHxA, its salts and PFHxA-related substances (Annex XVII, entry 79), EUR-Lex. https://eur-lex.europa.eu/eli/reg/2024/2462/oj/eng
• Code de l’environnement, Article L.524-1 (introduced by Loi n° 2025-188 of 27 February 2025) — French PFAS ban product list and dates (consumer clothing textiles, footwear, waterproofing agents, cosmetics, ski wax from 1 January 2026; all textiles from 1 January 2030). Promulgated text on Légifrance: https://www.legifrance.gouv.fr/codes/article_lc/LEGIARTI000051266190/2025-04-15
• Décret n° 2025-1376 du 28 décembre 2025 relatif à la prévention des risques résultant de l’exposition aux substances perfluoroalkylées et polyfluoroalkylées (France), Articles D.525-2 to D.525-4, Légifrance. https://www.legifrance.gouv.fr/jorf/id/JORFTEXT000053201526