CHINA REACH: IECSC SEARCH GUIDE
An IECSC search is an essential starting point for assessing a chemical substance's status in China. However, a CAS number search or a matching generic name alone may not resolve the substance's identity. Manufacturers, overseas suppliers and Chinese importers should cross-check the available identity information and clarify uncertain results before deciding on the next compliance step.
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What IECSC Listing Means Under China REACH
The Inventory of Existing Chemical Substances in China (IECSC) is the reference for distinguishing existing and new chemical substances. Under MEE Order No. 40, effective from 24 October 2026, a substance not listed in the IECSC is a new chemical substance.
The inventory covers substances present in China before 15 October 2003 and those subsequently included under the relevant provisions. Review subsequent additions and amendments alongside the inventory.
A listed substance subject to new-use environmental management is managed as new when used for industrial purposes outside its permitted uses. Assess product scope and exclusions separately, including the rules for raw materials and intermediates.
Where to Search the IECSC
Start with the MEE's official IECSC query page. Its query interface is delivered through the government services system and requires JavaScript. The following routes serve different purposes.
| Official Route | Purpose | Points to Check |
|---|---|---|
| MEE IECSC query | Search for the relevant substance using the available query fields. | Check the identity behind the result and any displayed management or use information. |
| MEE inventory announcements | Review official additions and amendments to the inventory. | Read the relevant announcement and attachments, including any conditions attached to the entry. |
| MEE-SCC technical identification | Seek technical assessment for complex or difficult substance identities. | Prepare the identity and supporting information required for the assessment; do not treat it as a keyword search. |
MEE-SCC's published system guidance also describes inventory access through the MEE government services platform: select the new chemical substances category, the registration certificate approval item, the application entry and then the inventory query. Follow the current on-screen instructions, as interface labels and access arrangements may change.
Why CAS Numbers and Generic Names Need Cross-Checking
A CAS number is a useful search identifier, but the assessment must address the actual substance being manufactured or imported. A search result under a related name does not, by itself, demonstrate that the supplied material is the same substance.
Useful identity information includes the CAS number; recommended Chinese name, Chinese alias and Chinese generic name; recommended English name, English alias and English generic name; molecular formula; and structural formula. Assemble the relevant information for cross-checking, while recognizing that not every field is necessarily searchable or publicly displayed.
Polyamide resin illustrates the difficulty. This broad description can refer to materials made from different reactants and associated with different CAS numbers. A listed entry bearing a broad resin name should therefore not be assumed to cover every product sold under that name. Compare the specific chemical identity and, where relevant, the reactants and production information.
For identity assessment, molecular and structural information can be decisive. MEE-SCC's technical identification guidance explains that formulas and structures are needed to judge whether a substance is the same as an inventory substance. A practical preparation checklist should therefore combine names and identifiers with the supporting chemistry, rather than relying on the product's trade name.
How to Handle an Unclear IECSC Search Result
Treat a failed or ambiguous search as a reason for further checking. The recommended approach is to resolve the identity question before committing to a registration strategy.
Check the input. Confirm the CAS number and chemical names against reliable supplier information and resolve inconsistencies.
Review the relevant entry. Compare the available names, formulas and structural information with the actual substance. A related generic name is not a conclusive match.
Check subsequent inventory announcements. Confirm whether an addition or amendment affects the substance or its listed conditions.
Escalate unresolved identity questions. For complex substances, consider the MEE-SCC technical identification service and confirm the current submission requirements.
The MEE-SCC technical identification service uses supporting chemical information, database research and specialist input for difficult cases. Its purpose includes avoiding both missed registration caused by incorrectly treating a new substance as existing and unnecessary work caused by treating an existing substance as new.
After clarifying status, assess scope, use and registration requirements. An inventory search is not a registration certificate. Where registration is required, obtain the relevant certificate before manufacture or import.
How REACH24H Can Help
REACH24H supports IECSC screening and China REACH compliance assessment for overseas suppliers and China-based businesses. Our team can help connect substance identity findings with the next steps for the planned supply arrangement.
Review substance identity information and identify unresolved inventory screening questions.
Assess the applicable registration pathway, applicant arrangements and available data.
Support preparation for the relevant China new chemical substance registration requirements.
Need to Clarify Your Substance's IECSC Status?
Share your substance identity information, intended use and China supply arrangement with REACH24H to discuss unresolved screening questions and the appropriate compliance steps.
