How Do I Find INCI Names and CAS Numbers for Perfumery Materials and Document Them for Compliance?

Every compliance document starts with a list of what is in the product, and the list has to use the right names. The label must use INCI names under Article 19 of Regulation (EC) No 1223/2009 and the UK regulation enforced through the Cosmetic Products Enforcement Regulations 2013, the safety report's Part A must identify every substance well enough to check it against the annexes and profile it, and the annexes themselves identify substances by chemical name and CAS number. Perfumery materials are where this gets hardest: a fragrance oil is one thing on the label and fifty things in the assessment, an essential oil has a Latin name and a variable composition, and an aroma chemical may go by three trade names. The CosIng database and the ECHA chemicals database exist to sort this out, and this guide shows how to use them.

It explains what INCI names and CAS numbers are and why both matter, where to find them for fragrance oils, essential oils and aroma chemicals, how fragrance blends, essential oils and blended raw materials are handled differently, the databases and how to search them, the common naming errors that stall assessments and labels, how to build an ingredient register that feeds the formula, the CPSR and the PIF, how the names flow onto the label, a worked example of documenting a three fragrance range, and the free tools that speed it up. Get the names right once and every document after them is easier.

What are INCI names and CAS numbers, and why do I need both?

INCI, the International Nomenclature of Cosmetic Ingredients, is the standardised naming system for cosmetic ingredients, maintained by the Personal Care Products Council and adopted in the EU's CosIng database and in UK law. The system is also published as the International Cosmetic Ingredient Dictionary and Handbook, which is the reference most assessors turn to when they need to identify cosmetic ingredients precisely rather than by trade name. Every ingredient on a cosmetic label must be written in its INCI name, in descending order, so that a consumer, a doctor or an inspector anywhere reads the same name for the same substance: Aqua, Glycerin, Simmondsia Chinensis Seed Oil, Parfum, Linalool. A CAS number is a unique registry number assigned by the Chemical Abstracts Service to each distinct chemical substance; it identifies the substance regardless of what anyone calls it, and the Cosmetics Regulation's annexes, supplier documents and toxicological databases use it. You need the INCI name for the label and the CAS number for the safety assessment and the annex screen, and an ingredient register that holds both is the bridge between the two.

Where do I find them for a fragrance oil?

A fragrance oil is a proprietary blend, and its supplier will not give you a full recipe, but the documents you need still exist. The Safety Data Sheet, section 3, lists the classified constituents with CAS numbers and concentration ranges. The allergen statement lists the declarable allergens with their percentages, and each allergen has an INCI name and a CAS number that the assessor uses. The IFRA certificate identifies the concentrate by name and code. On your label the whole blend is one ingredient, Parfum, followed by the allergens above threshold by their INCI names; in your formula and your CPSR the blend is recorded by its trade name, supplier and code, and expanded to its constituents from the SDS and allergen statement. Ask the supplier for a constituent breakdown under confidentiality if the assessor needs more; many will disclose to an assessor what they will not disclose to a customer.

Where do I find them for an essential oil?

An essential oil has a botanical INCI name of the form genus, species, plant part and preparation: Lavandula Angustifolia Oil, Citrus Limon Peel Oil, Mentha Piperita Leaf Oil, Rosa Damascena Flower Oil. The name appears on the supplier's specification and SDS and can be verified in CosIng, which also gives the oil's own CAS number, sometimes more than one. The oil's constituents, which matter for allergen declaration and the safety assessment, have their own INCI names and CAS numbers: Linalool, Limonene, Geraniol, Citral and so on. A gas chromatography certificate of analysis gives their percentages for the batch. On the label the oil appears by its botanical name and, because several essential oils are now allergens in their own right on the expanded EU list, may also need to be treated as a declared allergen; the constituents above threshold are named after it.

Where do I find them for an aroma chemical?

Single aroma chemicals are the easiest case. The supplier's SDS gives the chemical name and CAS number, and CosIng gives the INCI name, which for many aroma chemicals is the chemical name itself: Benzyl Benzoate, Coumarin, Hydroxycitronellal. Check the material against the annexes by CAS number, because several fragrance molecules are restricted under Annex III or prohibited under Annex II regardless of IFRA status, and check the allergen list, because many are declarable allergens. An aroma chemical used on its own in a formula is listed on the label by its INCI name and not as Parfum. Getting INCI names for every raw material right at this stage, before the formula is finalised, is what keeps the finished ingredient list and the product labels consistent with the CPSR later.

A note on INCI nomenclature conventions and updates

INCI nomenclature conventions are not static: the Personal Care Products Council periodically reviews entries, and an INCI name change can occur when a substance is reclassified, renamed or split into more specific entries. A brand working from an older specification sheet should check the current CosIng listing before finalising a label, since an outdated international cosmetic ingredient name on a pack can create exactly the kind of label-to-CPSR mismatch assessors are trained to catch.

How do I search the databases?

CosIng, the European Commission's cosmetic ingredient database, is searched by INCI name, chemical name, CAS number or EC number and returns the INCI name, the CAS and EC numbers, the functions, and any restriction or annex entry, with a link to the relevant annex. It is free and it is the authority for INCI names in the EU and, in practice, the UK. The PCPC INCI dictionary is the source CosIng draws on and is available by subscription with a free lookup for many names. ECHA's chemicals database, searched by CAS number or name, gives the substance's identity, classification and registration information under REACH, and is where to confirm a CAS number matches the substance you think it does. For botanicals, CosIng's naming of plant part and preparation is definitive; a supplier who writes Lavender Oil should be corrected to Lavandula Angustifolia Oil, and the CAS number checked, before the material enters your register.

What are the naming errors that stall assessments and labels?

• Trade names on the label. Optiphen, Emulsifying Wax NF and similar are not INCI names; each must be broken down.
• Common names instead of INCI. Lavender oil, vitamin E, shea butter; the label needs Lavandula Angustifolia Oil, Tocopherol, Butyrospermum Parkii Butter.
• Fragrance oil listed by its scent name. Vanilla Amber is not an ingredient; the label says Parfum plus allergens.
• Blends listed as one ingredient. An emulsifying wax is two or three INCI names; a preservative blend is two or more.
• Missing plant part. Citrus Limon Peel Oil and Citrus Limon Fruit Extract are different materials.
• Wrong or missing CAS numbers. A CAS number for a different isomer or a related substance sends the assessor to the wrong data.
• Allergens omitted after Parfum. The names must follow, calculated from the allergen statement.

How do I build an ingredient register?

A single spreadsheet with one row per material and these columns: INCI name; trade name and supplier; CAS number and EC number; function in your formulas; which products use it and at what percentage; the documents held, with dates, for the SDS, specification, IFRA certificate, allergen statement and certificate of analysis; the current lot number in use; any annex restriction found; and a review date. Fragrance oils and essential oils get a second sheet listing their constituents with INCI names, CAS numbers and percentages from the allergen statement or analysis. The register feeds three things directly: your formula sheets, which take INCI names and percentages from it; your CPSR submission, which takes the whole row and its documents; and your Product Information File, where the register itself is filed with the raw material documents. When a regulation changes, the register is how you find in minutes which products are affected.

How do the names flow onto the label?

The label ingredient list is built from the formula: every ingredient by INCI name in descending order of weight above one percent, then in any order, with Parfum standing for each fragrance blend and the declarable allergens named after it, essential oils by botanical name, colourants by CI number after the other ingredients, and nano ingredients marked. Blended raw materials are listed by their components in the correct positions, which means an emulsifying wax's components may appear in two different places in the order depending on their weights. The free INCI List Generator produces the ordered list from a formula, and the free Fragrance Allergens Checker calculates which allergens follow Parfum. A label review then confirms the list against Part A of the CPSR.

A worked example: documenting a three fragrance range

A maker launches a body oil in three scents: a fragrance oil, a lavender essential oil and a single aroma chemical accord of two molecules. For the fragrance oil the register records the trade name and code, the supplier, Parfum as the label name, and the constituent sheet takes the SDS section 3 entries and the allergen statement's percentages: coumarin, benzyl benzoate and linalool with CAS numbers. For the lavender the register records Lavandula Angustifolia Oil, its CAS number from CosIng, the supplier and lot, and the constituent sheet takes the gas chromatography certificate: linalool, linalyl acetate, limonene and geraniol with percentages. For the accord the register records the two molecules by INCI name and CAS, both checked against Annex III and both found to be declarable allergens. The formula sheets pull INCI names and percentages; the INCI generator produces three ordered labels with Parfum plus three allergens, the botanical name plus four, and two named molecules; the assessor receives the register and the documents and writes a multiple fragrance CPSR in days. When the EU allergen list expands, the maker filters the constituent sheet for the new names and finds in a minute that one product is affected.

How does the assessor use the names?

Part A section 1 of the CPSR records every ingredient by INCI name, trade name and supplier with its percentage, and the assessor uses CAS numbers to screen each against Annex II and III and, for colourants, preservatives and UV filters, against the positive lists, and to retrieve toxicological data for section 8. Fragrance blends are expanded to their constituents by CAS number so each sensitiser and phototoxic material can be assessed and the allergen declaration calculated. A submission that arrives with INCI names, CAS numbers and documents matched to lot numbers is the fastest kind to assess; one that arrives with scent names and common names spends its first week being translated. Our guide to preparing for a CPSR sets out the submission and our guide to reading an SDS shows where the numbers sit.

Myths we hear

• The scent name is the ingredient name. The label says Parfum; the scent name is marketing.
• Lavender oil is an INCI name. Lavandula Angustifolia Oil is.
• An emulsifying wax is one ingredient. It is two or three INCI names.
• CAS numbers are only for chemists. They are how the annexes and the assessor identify what you used.
• I can copy the INCI list from a similar product. Your list comes from your formula, in your order.

What to do this week

• Start the ingredient register with the columns above.
• Look up every material in CosIng and correct the names.
• Build the constituent sheet for every fragrance and essential oil from the allergen statement or analysis.
• Regenerate your labels from the register with the INCI generator.
• File the register in the PIF.

Names are the foundation of every document that follows. A morning with CosIng and a spreadsheet saves a week of translation later, and a consultation can review a register before the first submission so the names are right from the start.

Official sources and legislation

• CosIng, the European Commission cosmetic ingredient database
• PCPC INCI dictionary
• ECHA information on chemicals
• Regulation (EC) No 1223/2009 on cosmetic products, Article 19
• OPSS guidance on cosmetic products regulations

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.