Identify all available information
The first step is to identify all relevant available information on the mixture itself and on the individual substances in the mixture, as needed. It is important to know that for certain hazards, classification is always based on the individual substances in a mixture. Therefore you need a clear picture on the hazards of the substances in your mixture. Your primary source of information should be your suppliers.
- All existing in-house information on the mixture and the substances in the mixture.
- An up-to-date safety data sheet or another format of safety information, provided by your supplier(s), for the imported mixture or for the substances and/or mixtures to be incorporated in a formulated mixture.
- Classification under the transport legislation from your supplier.
- A transport classification done in accordance with the UN Recommendations on the Transport of Dangerous Goods - Model Regulations, or the model regulations for transport over road (ADR), rail (RID), inland waterways (ADN), air (ICAO TI) or sea (IMDG), may indicate a need to look further at the hazards of the substance or mixture.
- Even though the classification criteria used in transport classification and under CLP are mostly the same, the transport regulations have a different scope and transport classification does not necessarily cover all of the hazards that a mixture may have.
- The Classification and Labelling Inventory on the ECHA website, which contains:
- Classifications of substances harmonised at EU-level (Table 3.1 of Annex VI to CLP). The harmonised classification and labelling of a substance is legally binding in the EU/EEA and must be taken into account in the classification of a mixture containing such a substance.
- Classifications of substances as provided by manufacturers and importers in their C&L notifications or registration dossiers. Such a classification includes any applicable harmonised classifications as well as self-classifications for those hazards that are not covered by the harmonised classification.
- ECHA's publicly available database with information on registered substances. This can be accessed from the ‘Search for Chemicals' field on the Information on Chemicals page on the ECHA website.
- Further sources e.g. the OECD eCHEMPortal and other sources listed in Chapter 9 of the Introductory guidance on the CLP Regulation.
- Opinions of internationally recognised technical scientific committees (especially the Risk Assessment Committee of ECHA) or other information on the ECHA website should also be taken into account as new scientific evidence.
The basic information you need to list for each substance in the mixture would include:
a. the identity of the substance
b. the concentration of the substance in the mixture,
c. its classification and any assigned specific concentration limits (SCL) or multiplying factors (M-factors),
d. details of any impurities and additives in the substance, including their identity, classification and concentration may also be relevant. Generally substances present at 0.1 % or above should be taken into consideration, but the relevant concentration ultimately depends on the hazard class and the substance.
If a component in the mixture is itself a mixture, it is necessary to get information on the substances of that component mixture together with their concentrations, classifications and any applicable SCLs or M-factors.
CLP requires that ‘all available' data or information must be taken into account for the purposes of classification.
Specific information may be test data on the mixture itself, or the substance(s) in the mixture, e.g. in the form of:
- study reports
- study summaries
- relevant parameters from test data (e.g. acute toxicity estimate values)
A concentration limit is the minimum concentration of an individual substance that triggers the classification of a mixture or the sum of concentrations of relevant substances where the effect of several substances is additive.
Concentration limits can be generic for a hazard class, differentiation or category (generic concentration limit, GCL) or they may be specific for a particular substance (specific concentration limit, SCL). An SCL may be assigned to a substance, based on its potency, to allow the fine tuning of its contribution to the classification of a mixture. The SCL concept is mainly applicable to health hazards. SCLs take precedence over the GCLs.
For the hazard class ‘Hazardous to the aquatic environment', the multiplying factors (M-factors) concept is used instead of SCLs. The M-factors have been established to give an increased weight to substances classified as hazardous to the aquatic environment (categories Acute 1 or Chronic 1) when classifying mixtures. They are used to derive the classification of a mixture in which the substance is present.
For further details, see Chapter 1.5 of the Guidance on the application of the CLP criteria.