The ZDHC Manufacturing Restricted Substances List (MRSL) V4.0 was published on 4 November 2026. The new version updates restrictions on chemicals used in manufacturing processes and provides clearer guidance to support the assessment and implementation of chemical formulations across the supply chain.
For brands, chemical formulators and suppliers, the revision is an opportunity to review how the updated requirements fit into existing chemical management programmes and procedures. The changes may affect formulations, assessment criteria, documentation and control activities.
The main updates in MRSL V4.0
The new version adds 16 substances, places three substances on the Candidate List and moves two to the Archived Substances List. Titanium dioxide has been removed from the MRSL following changes to its regulatory classification.
The revision also updates formulation limits, analytical methods and applicability guidance. For example, the limit for NPEO and OPEO has been reduced from 250 to 100 mg/kg, while the limit for 1,2-dichlorobenzene has decreased from 500 to 20 mg/kg. Requirements have also been updated for several substance groups, including flame retardants, solvents, PAHs and UV absorbers.
MRSL V4.0 introduces new substance groups, including bisphenols, aldehydes and ketones, PCBs, and oxidising and reducing agents. Companies should assess these updates in relation to the materials and formulations they use, as well as their existing procedures.
PFAS: requirements for chemical formulations
MRSL V4.0 clarifies ZDHC’s position on PFAS: intentionally added PFAS are not permitted in MRSL-conformant chemical formulations. The guidance also addresses how to manage potential unintentional contamination.
For targeted PFAS analysis, the MRSL refers to the AFIRM V11 list and recognises the EN 17681-1:2025 method, based on alkaline hydrolysis. It sets a limit of 25 µg/kg for an individual PFAS and 250 µg/kg for the sum of PFAS. Total fluorine is used as a screening parameter: above 50 mg/kg, the presence and source of fluorine must be disclosed to the solution provider. PFAS testing at ZDHC MRSL Level 1 is mandatory.
The application of these requirements depends on the formulation and the relevant assessment programme. Thresholds should therefore be considered in context, alongside the applicable requirements and the characteristics of each case.
MRSL V4.0 transition dates
ZDHC has established a phased transition:
- 1 November 2026: transition begins.
- 15 December 2026: the Solution Provider Platform (SPP) opens for certifiers to submit V4.0 approval applications.
- 1 February 2027: the list of ZDHC Approved Certifiers – MRSL for V4.0 is published, and formulation recertification begins.
- 1 June 2028: full supply chain implementation.
For certifiers, the transition includes a new approval process for certification against V4.0. They will need to review the applicable requirements and update their procedures, certification criteria and documentation where necessary. Brands, formulators and suppliers can use the transition period to assess the potential impact on their processes and coordinate next steps with supply chain partners.
How to prepare
Start by identifying the substances and formulations covered by your programme. Then assess whether the updated requirements call for changes to your procedures or to the information you collect from suppliers.
Involving the teams responsible for chemical management, quality, compliance and sustainability can help assess the updates against current processes and responsibilities. ZDHC has also scheduled webinars to help stakeholders understand the changes and use the relevant implementation documents.
Understanding how MRSL V4.0 applies to a specific company, formulation or supply chain requires consideration of its operational context.
Analytical supports brands and suppliers in interpreting requirements and planning relevant checks, bringing together testing, compliance and technical expertise. Contact us to assess how MRSL V4.0 may affect your programme and identify the next steps for your supply chain.