Composition disclosure and concentration ranges

Why ranges exist

A formulation rarely stays at the exact same percentage from one production batch to the next, and requiring an exact figure for every component would mean re-submitting for variation that has no bearing on how a poison centre would respond to an exposure. Annex VIII solves this with concentration ranges: bands wide enough to absorb ordinary batch variation, narrow enough that a poison centre still knows roughly what it is dealing with. The width allowed is not the same for every component — it narrows sharply as the hazard gets more serious, because precision matters more when the answer affects emergency treatment.

The ranges for hazardous components

Components classified for acute toxicity (Category 1, 2 or 3), specific target organ toxicity from a single or repeated exposure (Category 1 or 2), skin corrosion (Category 1, 1A, 1B or 1C), or serious eye damage (Category 1) are treated as components of major concern. The default requirement for these is an exact percentage, stated in descending order by mass or volume. As an alternative, a range may be declared instead, but only within the narrow bands below — the maximum width allowed shrinks as the concentration falls, which is the opposite of what intuition might suggest, but reflects how much a small absolute amount can still matter at low concentrations.

The ranges for non-hazardous components

This second table covers two groups at once: components classified for a hazard that falls outside the major-concern list above, and components that are not classified as hazardous at all but still have to be identified. Both may be declared as a range instead of an exact figure, and the bands here are noticeably wider, because the emergency-response case for precision is weaker.

Where an exact concentration sits right at the boundary between two allowed widths, the rule is to use the narrower one — a component at 26% cannot be declared as 23.5–28.5% just because that range is technically wide enough, if a tighter band starting from a lower boundary is also available.

When exact concentrations are required

Exact percentages are the baseline expectation for the five hazard categories of major concern listed above; the range in the first table is offered as an alternative, not the default. In practice, because that alternative is already narrow, many formulators declare the exact figure directly rather than working out which tight band it falls into. Once a mixture is on file, how much an exact figure or a range is allowed to move before the dossier needs a fresh submission — an update, or in some cases a new UFI — is a separate question; our guide to when a new UFI is needed works through it.

Components you must always name

Any component classified as hazardous has to be individually identified once it reaches 0.1% of the mixture, and below that threshold too, unless you can actually demonstrate it is irrelevant to emergency health response — omitting it because it seems unlikely to matter is not the same as demonstrating that. Components not classified as hazardous only need to be named once they reach 1%. The one narrow exception to naming a component by its real chemical identity is a generic identifier — "perfumes", "fragrances" or "colouring agents" — and even that is only available where the component carries no health hazard classification of its own, and the combined total stays under 5% for fragrance components or 25% for colouring agents. Outside that exception, a marketing name is never a substitute for the actual substance identity in section 1.4 of the dossier.