Hair Dyes and Hair Colour Products: The Strictest Labelling in Cosmetics, the Allergy Alert Test, and What the CPSR Requires

A small brand wanted to launch a natural hair colour line: henna, indigo, a couple of botanical shades and a semi permanent gloss with a synthetic dye for the tones the plants could not reach. The founder assumed the natural products were unregulated and the gloss was a simple cosmetic. Both assumptions were wrong in ways that matter. Hair colourants are the substances the Scientific Committee on Consumer Safety has reviewed more thoroughly than any other category, and the results fill Annex III of Regulation (EC) No 1223/2009 with entries that set maximum concentrations and prescribe warnings word for word, enforced in Great Britain through the Cosmetic Products Enforcement Regulations 2013. Hair dye sensitisation is real, occasionally severe, and the labelling reflects it.

This guide explains why hair dyes are regulated so tightly, the difference between oxidative, non oxidative and natural colourants and how the rules treat each, the Annex III entries and their maximum concentrations, the mandatory warning block and where each statement comes from, the allergy alert test and its status, hydrogen peroxide and developers, henna and the black henna problem, professional products, how the CPSR handles a hair dye and why the exposure model is different, labelling for two part products, a worked example of the natural range, and the mistakes that stop hair colour products at the assessment. The founder launched. The gloss took longer than the henna.

Why hair dyes are regulated so tightly

Hair colouring involves applying reactive chemicals to the scalp, one of the most permeable and sensitive areas of skin, leaving them for up to an hour, and repeating every few weeks for years. The permanent colourants that make this possible, aromatic amines such as p-phenylenediamine and toluene-2,5-diamine developed with hydrogen peroxide, are among the most potent skin sensitisers in common use, and severe allergic reactions to hair dye, including facial swelling and hospitalisation, occur every year. The European Commission asked the SCCS to review every hair dye substance in use, over more than a decade the committee issued opinions on well over a hundred, substances without adequate data were banned, and those with data were restricted with maximum concentrations and warnings. The result is a category where the rules are precise, the warnings are prescribed, and the assessor's job is largely to apply them correctly.

Oxidative, non oxidative and natural

The Annex III entries and maximum concentrations

Each restricted hair dye substance has an Annex III entry stating the maximum concentration, usually expressed as the maximum on head concentration after mixing with the developer for oxidative dyes, sometimes with a limit on the concentration in the product as sold, and any other conditions such as a restriction to professional use or a prohibition on combination with certain other substances. p-phenylenediamine, for instance, is limited to a maximum on head concentration after mixing, and the assessor must calculate that figure from the dye cream's concentration and the mixing ratio with the developer. Several entries also specify the exact warning wording, and some require the substance's presence to be stated on the label in a defined form. The assessor applies every entry for every dye substance in the product and records the calculation in Part A.

Hydrogen peroxide and developers

Hydrogen peroxide in hair products is limited to twelve percent present or released, with its own warning requirements including gloves, rinsing the eyes and keeping out of the reach of children, and with additional conditions for professional products. Developers sold separately are cosmetics in their own right with their own CPSR, and a dye sold as a kit with a developer is a multi component product whose CPSR covers both components and the mixture. Persulfate bleaches are restricted with professional use conditions and warnings about inhalation and skin contact. The assessor applies the peroxide and persulfate entries alongside the dye entries, and the exposure assessment considers the mixed product on the scalp.

Henna, indigo and the black henna problem

Henna, Lawsonia inermis, is a permitted cosmetic ingredient assessed by the SCCS, and pure henna and indigo hair colour products are cosmetics needing a CPSR like any other, with the assessor looking at the botanical's data, its microbiological quality as a dry plant powder mixed with water at home, and any additives. Natural does not exempt them from the CPSR, the PIF or notification. The serious problem in the category is black henna: henna adulterated with p-phenylenediamine at high concentration to give a fast dark stain, sold for temporary tattoos and sometimes for hair. PPD at those levels on skin is a potent sensitiser, black henna tattoos are the reason the black henna warning exists on every hair dye pack, and any henna product found to contain PPD outside the strict conditions for oxidative hair dye is unlawful. A natural brand must be able to show, with a certificate of analysis, that its henna contains no PPD.

Professional products

Hair colour products for professional use are not exempt from the regulation. They need a CPSR and a PIF, notification, and labelling, and they carry their own conditions: for professional use only where the entry restricts the substance, professional specific warnings about gloves, ventilation and mixing, and sometimes higher permitted concentrations than consumer products on the basis that a trained user applies them. A product sold to consumers with professional use only on the label does not become compliant by the label; the assessor assesses it for the use it will foreseeably have, and a professional product sold through a consumer marketplace is a consumer product in the assessor's eyes.

How the CPSR handles a hair dye

A hair dye CPSR is among the most demanding a safety assessor writes. Part A section 1 records every dye substance, the concentration in the product as sold, the mixing ratio and the on head concentration after mixing. Section 5 records an application model specific to hair colouring: amount applied, contact time, frequency, and whether the product is rinsed off after development. Section 8 profiles each dye substance on the SCCS opinion behind its annex entry. Part B then checks every substance against its entry and conditions, specifies the full warning block, the gloves and eye rinsing directions, the mixing instructions, any professional restriction and the required statements of presence, and sets the conditions for the product. For a range of shades the multiple variant approach applies, with each shade's dye substances and on head concentrations tabulated. Our guide to multiple variant CPSRs covers shade ranges, and the claims guide matters here too, because hair dye marketing is prone to gentle and ammonia free claims that need substantiation.

Labelling a two part product

A dye cream and a developer sold together are a kit whose outer packaging carries the mandatory warning block, the ingredient lists for each component, the mixing instructions, the Responsible Person, the batch codes and the durability information, with each component's container labelled with its own identity and batch. Where the components are also sold separately, each needs its own complete label. The warning block must be visible on the outer pack before purchase and the full instructions must be inside; a leaflet is standard and expected in this category. Our label review checks the warning block against the annex wording, which is the most common error we see on hair colour packaging.

A worked example: the natural hair colour range

The founder's range has four products. The pure henna and the henna and indigo blend are cosmetics; the assessor reviews the botanical data, requires a certificate of analysis showing no PPD, considers the powders' microbiological quality and the home mixing with water, and issues CPSRs with warnings about patch testing for botanical sensitivity and keeping the mixed product out of the eyes, but no mandatory hair dye block because no restricted dye substance is present. The cassia based blonde treatment follows the same route. The semi permanent gloss contains two HC direct dyes with Annex III entries, one of which carries the allergy alert warning requirement. The assessor checks each against its maximum, finds one slightly over, and the gloss is reformulated to bring it within; Part B specifies the full warning block including the under sixteen and black henna statements, and the gloss label is redesigned with the block on the outer pack. The three botanical products launch in a month. The gloss launches two months later with a label that looks very different from the others, which is exactly as it should be.

Mistakes that stop hair colour products at the assessment

• Calculating limits on the product as sold rather than on head after mixing.
• Copying a competitor's warning block that predates the current wording.
• Leaving off the under sixteen or black henna statements as irrelevant to a natural product that contains a restricted dye.
• No certificate of analysis for henna, or henna that turns out to contain PPD.
• Selling a professional product through a consumer marketplace.
• Ammonia free, gentle or hypoallergenic claims on a product carrying the allergy alert block.
• A developer sold separately with no CPSR of its own.

Myths we hear

• Natural hair colour is unregulated. It is a cosmetic needing a CPSR, and henna must be shown to be PPD free.
• Semi permanent dyes do not need the warnings. Many direct dyes carry the allergy alert requirement in their entries.
• The patch test instruction replaces the warnings. It does not; the warning block is mandatory and the test is not a guarantee.
• Professional use only on the label makes a product exempt. It is assessed for its foreseeable use.
• Ammonia free means gentle. It is a claim needing substantiation and does not remove the sensitisers.

What to do this week

• List every dye substance in your range with its Annex III entry and maximum.
• Recalculate every limit on head after mixing.
• Compare your warning block with the current annex wording, word for word.
• Obtain a PPD free certificate of analysis for any henna.
• Check where professional products are actually being sold.

Hair colour is the category where a consultation before formulation prevents the most reformulation, because the maxima are precise and the warnings are fixed, and every Phoenix CPSR for a hair dye tabulates each substance, its on head concentration and its entry so you can see exactly why the label says what it says. The natural range launched on time. The gloss launched compliant. Both are on sale.

Official sources and legislation

• Regulation (EC) No 1223/2009 on cosmetic products, Annex III hair dye entries
• Cosmetic Products Enforcement Regulations 2013
• Scientific Committee on Consumer Safety (SCCS), hair dye opinions
• OPSS guidance on cosmetic products regulations
• Office for Product Safety and Standards

Disclaimer: This article is general information, not legal advice. Regulations change and product decisions depend on your exact formulation, claims and market. Have your product assessed by a qualified professional before sale.