ECJ EUROPEAN Cleaning Journal

Dr Sandra Meijer and Dr Kath Carr of The REACH Centre share their learning on the substance identity and sameness checking process - in this exclusive article for ECJ.

The ingredients in cleaning products are subject to REACH registration therefore it is important for the manufacturers of these products to ensure they are compliant with the regulation. Whilst many of the large-scale substances have already been registered prior to the 2010 or 2013 deadlines, a very significant number of the smaller volume substances (1-100 tonnes/year) are yet to be registered before the final REACH deadline of May 31 2018.

Compared to the earlier deadlines, additional challenges are expected this time around, especially for those substances that do not yet have a Lead Registrant. ECHA’s database shows that many surfactants and other cleaning product ingredients including various fatty acid salts, ethoxylated alcohols, and sulphonate salts have not yet been registered by anyone in industry at the time of writing of this article.

It’s essential that companies start to look at their portfolio now, so as to allow enough time for all the necessary activities needed to complete a successful REACH registration.

The activities you must undertake depend on whether you will be a Joint Registrant (JR) or the Lead Registrant (LR). However the process for everyone generally involves, in order of listing:

• Sameness check
• Data sharing (cost sharing)
• Dossier build in IUCLID
• Submission
• Payment of ECHA fees

Whether you will be acting as LR or submitting a registration as JR, whether you will need to make an inquiry or already have a valid pre-registration in place, substance identity and sameness checking are the first steps and are crucial to getting the right registration in place. It will allow you to ascertain that you are in the right SIEF and it is an essential requirement of any REACH dossier that you prove the substance identity to ECHA.

In this article we will discuss the issues around substance identity and share some case studies.

Substance identity

According to the ‘one substance one registration’ (OSOR) principle of REACH, companies are required to work together in a substance information exchange forum (SIEF) to share the costs of compiling the hazard data and submit these jointly.

However sharing hazard data is only possible if the jointly registered substances are “the same”. Robust substance characterisation data are essential to demonstrate identity and composition and to check whether the substance fits within the scope of the Substance Identification Profile (SIP) agreed with the SIEF.

Characterisation presents evidence that the substance manufactured or imported by the registrant is the same as that being described in the registration dossier. Different strategies will be needed for different types of substances.

Under REACH, a substance may be classified as well-defined, ie, with a defined qualitative and quantitative composition. This category can be divided into mono- and multi-constituent substances, defined by their quantitative composition, in which the main constituent is present to at least 80 per cent (w/w) or >10 per cent (w/w) and <80 per cent (w/w) respectively.

Alternatively substances might be defined as unknown or variable composition, complex reaction products or biological (UCVB) materials. Here, the number of constituents is relatively large and/or the composition is, to a significant extent, unknown and/or the variability of the composition is relatively large or poorly predictable.

By their very nature, UVCB substances can present a difficult analytical challenge and their characterisation may demand a somewhat different approach to that used for well-defined substances. Typical examples of UVCBs include petroleum products, plant-derived essential oils and complex inorganic species, such as synthetic minerals.

A substance is defined by the identity and relative quantity of both its main component and its impurities. Characterisation must provide evidence that the substance being manufactured can be described by the identity shown in the registration dossier.

Whilst Annex VI of REACH (Section 2: Identification of the Substance) lists certain spectroscopic and chromatographic techniques as part of the substance identity information requirements, in practice there is no defined set of tests that must be used for the characterisation of any substance.

Rather, sufficient analysis should be performed to identify and quantify all components in the substance at ≥1 per cent (w/w) or Substances of Very High Concern at ≥0.1 per cent. The choice of an appropriate suite of orthogonal analytical techniques is critical.

Substance characterisation

Anyone designing an analytical strategy for REACH registration must take several factors into account. First, the strategy must be able to identity and quantify all of the major constituents in the substance. In addition, any impurities present at a concentration of ³one per cent w/w should be identified, then specified by chemical name, EC and/or CAS number and/or molecular formula.

Knowledge of the manufacturing process is useful for highlighting any potential impurities that would be relevant to the classification or persistent, bioaccumulative & toxic (PBT) assessment of the substance, were they to be present in sufficient quantities.

The strategy should make provision for testing for such impurities and if they are found, they should be specified by the criteria listed above regardless of their concentration. The sum of the main constituents, impurities and any additives included to preserve the stability of the substance must be 100 per cent.

Scientific justification for tests not deemed to be appropriate must be provided. This is typically limited to the principal analytical techniques listed in Annex VI of REACH (Section 2: Identification of the Substance).

Finally, the results should be fully interpreted and all experimental details (and reference materials used) comprehensively documented such that a competent person might, in principle, be able to repeat the work.

For UVCBs, the chemical composition and identity of the constituents should be given as far as known. This information can be provided in a generic way as appropriate, eg,. the carbon chain-length range. The analytical strategy may need to include the determination of other parameters that contribute to defining the substance. Boiling range, for example, would be an important property for a petroleum-based substance.

Typical concentrations and concentration ranges need to be given and all constituents present at a concentration of ³10 per cent should be specified by a IUPAC name and a CAS number. Unknown constituents should be identified using a generic description of their chemical nature if possible.

As with well-defined substances, knowledge of the source and manufacturing process is useful for highlighting any potential constituents that would be relevant to the classification or PBT assessment of the substance were they to be present in sufficient quantities. The analytical strategy should make provision for testing for such constituents and if they are found, they should be specified by a IUPAC name and a CAS number, regardless of their concentration.

Over the last few years, it has become clear that proving substance identity is not always straightforward. In 2013, having achieved its target of evaluating at least five per cent of all registration dossiers for the two highest tonnage bands by the end of 2013, the European Chemicals Agency (ECHA) issued its ‘Evaluation under REACH Progress Report’.

In this, the agency revealed 61 per cent of the dossiers checked did not comply with one or more of the information requirements of REACH. One main area of concern was substance identity. If an issue is raised following dossier evaluation and follow-up corrective action still fails to satisfy ECHA’s requirements, it may invalidate the registration and withdraw the registration number.

Within SIEFs, agreeing on sameness has also proved challenging at times. In many known cases, registrants had to redefine the substance identity based on SIEF discussions and chemical analysis and ended up registering their substance under a different EC or CAS number.

Many SIEFs were split as what was thought to be one substance turned out to be several different substances. In total, ECHA has recorded over 350 such substances, many of which were multi-constituent substances and UVCBs.

As agreeing sameness is the first and crucial step in the joint registration process, you need to start the discussions sooner rather than later. Once you have carried out the analysis, you may find that you pre-registered the wrong substance.

Case studies

The REACH Centre has extensive experience in this area:

Case Study 1 - One of The REACH Centre’s clients manufactures consumer and laundry detergents using the sodium salt of an organic diacid. The salt is added to products to improve their performance, especially with regard to stain removal. The salt is imported from a number of different sources and each individual product is known to vary slightly in certain respects such as the sodium content.

The client wanted to be sure that the material from all their sources fell within the SIP for the substance. The REACH Centre analysed batches of the salt from each of the different sources and checked their composition against the SIP. Sameness could be demonstrated for all the batches analysed and the client went away confident that they were in regulatory compliance and could retain the flexibility and security of their supply of material.

Case study 2 - A manufacturer of a quaternary ammonium salt used in detergents and textile softeners requested a sameness check by The REACH Centre. This was a complex case insofar as there were two critical variables that needed to be taken into account. The salt is prepared from a long-chain alkylamine in which there is a range of alkyl chain lengths. The range required for sameness was one of the parameters defined in the SIP.

In addition, residual amounts of one of the reagents used in the manufacturing process needed to be considered due to its relevance for classification. An analytical strategy was designed by The REACH Centre that allowed both the alkyl chain length range to be clearly demonstrated and the residual reagent to be quantified. This information was used to good effect and allowed the sameness assessment to be performed successfully.

Case study 3 - A client was planning to begin manufacture of an alkyl-substituted aromatic sulphonic acid. A number of these exist, differing principally in the length and distribution of the alkyl substituents, and they are UVCBs. Some have been registered; others have not, mainly because they have been found to fall into the SIP for other related substances.

The client commissioned The REACH Centre to undertake its substance characterisation, which defined the all-important alkyl chain length and distribution. It was then possible to compare the identity and composition of the substance with the known options and demonstrate sameness with the most appropriate of these.

Case study 4 - A client had pre-registered a long-chain fatty acid, which was a multi-constituent substance, comprising several acids of differing carbon chain lengths. Analytical characterisation unexpectedly revealed that the substance did not fit into the SIP issued by the SIEF.

By examining closely related substances and their respective SIPs, The REACH Centre was able to demonstrate sameness with a more appropriate substance. As a result, the client was able to fulfil its obligations and remain compliant.

j.friesl@thereachcentre.com

www.thereachcentre.com