IUCLID 6 and the PCN format

IUCLID 6 and the PCN format

IUCLID 6 is the software platform ECHA maintains for building regulatory dossiers — it is used for REACH registrations, biocidal product submissions and several other EU chemical regimes, not just poison centre notifications. Within it, the poison centre notification is one particular document type, structured according to the PCN format: a set of XML schema definitions that fix exactly which fields exist, how they relate to each other, and what a valid entry looks like. Whether you build the dossier by hand in IUCLID Cloud, work offline in the desktop application, or generate the XML programmatically through the system-to-system service, the output has to conform to the same schema before ECHA's Submission Portal will accept it.

Format versions and why they matter

The PCN format is not fixed once and left alone. It is revised roughly once a year, in step with IUCLID's own release cycle, to add fields the poison centre community has requested and retire ones nobody needs. As of September 2026, the current format is Version 8, published alongside IUCLID 6 v10 on 27 April 2026. A dossier built against an older template can look complete and still fail validation, because the portal is checking it against the schema in force now, not the one that was current when a company last touched its submission process. If your last PCN predates this year's release, it is worth confirming the tooling you or your provider used has actually been updated before you rely on it again.

Validation before submission

IUCLID includes a Validation Assistant that checks a dossier's completeness and structure before it ever leaves your account — missing mandatory fields, malformed identifiers, ranges outside the widths a hazard class allows. Running it is optional but strongly advisable, because the Submission Portal repeats these checks and adds its own once you actually submit: it verifies the UFI against ECHA's own records, checks the legal entity behind the dossier against the account submitting it, and cross-references the market information you have declared. A dossier that passes the Validation Assistant can still be refused at this second stage, because some of what the portal checks only exists on ECHA's side.

The errors that block a submission

A handful of causes account for most rejections and warnings:

• A mismatch between the legal entity registered on the submitting account and the legal entity named inside the dossier — this is usually caught before the composition data is even looked at.
• A concentration range wider than Annex VIII permits for that component's hazard class, most often because the exact figure sits right on the boundary between two allowed band widths.
• A limited submission for an industrial-use mixture missing the 24-hour phone number and email that the shorter composition disclosure depends on.
• Free-text fields left in one language when the submission covers a member state that requires its own official language.
• A trade name inside the dossier that no longer matches what is printed on the physical label.

If your submission was rejected

Start with the submission report itself — it names the rule that failed, not just that something did. A rejection means the notification never reached the appointed bodies at all and has to be corrected and resubmitted from scratch; a successful submission carrying warnings is a different situation, since the dossier is on file but a correction is still expected as an update. Either way, the product in question is effectively unsellable until the fix goes through, which makes a rejected PCN one of the more time-pressured problems we get asked to handle. If that is where you are, see how we take over a rejected dossier and get it resubmitted correctly rather than reworking it line by line yourself.