The concept of polymer of low concern (PLC)
The European Commission has taken the decision to remove the concept of a polymer of low concern (PLC) from its draft for the registration of polymers under REACH. The decision has been shared in joint documents with the competent authorities of the Member States.
This concept has long been a subject of debate during meetings of the competent authorities for REACH and CLP (CARACAL). Generally, the idea was supported by industry, but they also argued for a high degree of harmonization with existing non-European regulations that already incorporated it.
The Commission had shared a flowchart for identifying polymers requiring registration (PRR). The flowchart illustrates the concept with the Caracal Polymer Subgroup (CASG-Polymers). However, at the last meeting the PRR flowchart did not include the concept of PLC.
What are the reasons?
The lack of scientific evidence is one of the main reasons. The Commission announced that the identification of a PLC substance must be justified by scientific evidence. However, the Commission noted a lack of evidence for the categories of PLC in other jurisdictions. In addition, the lack of harmonization was also a relevant issue in making this decision.
It should be noted that the Commission has not yet given all the details on the procedure for registration. Further information is therefore expected in its final draft. Meanwhile, other entities such as CEFIC are questioning the usefulness of such an exclusion.
Criteria for identifying polymers of low concern
In 2021, the Commission had shared a revision of the criteria for polymers of low concern. The exclusion was based on water absorption and a European list of polyester reagents.
At that time, it was announced that the study for PLCs would be part of the EU strategy on chemicals.
Thus a new criteria was added to the list, which included 4 criteria:
- The molecular weight
- The reactive functional groups
- The approved polyesters
- Composition, iconicity, degradation and hazard classification
Increasing the criteria to 5.
What are my regulatory obligations for polymers?
Although polymers are not directly subject to the REACH provisions, their monomer constituents do require registration, if they meet one of the following two conditions:
- The polymer contains 2% weight by weight (w/w) or more of such monomer substance(s) or chemically bound substance(s)
- The total quantity of such monomer or other substance(s) reaches 1 ton or more per year (the total quantity in this context is the total quantity of monomer or other substance(s) that will be chemically bound to the polymer).
Classification and labeling rules are however mandatory for polymers, according to the CLP 1272/2008 regulation. It is also mandatory to notify ECHA, in case the polymer is classified as hazardous or at risk.
In Article 3, paragraph 5 of the REACH Regulation, the definition of a polymer is as follows:
« A substance consisting of molecules characterized by the sequence of one or more types of monomer units. These molecules must be distributed over a range of molecular weights, with differences in molecular weight due primarily to differences in the numbers of monomer units. A polymer includes:
- a simple majority by weight of molecules containing at least three monomer units covalently bonded to at least one other monomer unit or to another reactive substance;
- an amount less than a simple weight majority of molecules of the same molecular weight. For the purposes of this definition, "monomer unit" means the reacted form of a monomer substance in a polymer. »
When REACH came into force in 2007, polymers were not the priority for registration. This could be explained by the fact that not all polymers were considered as polymers under REACH.
Effectively, ECHA shared in 2012 a guidance on polymers, indicating that 50% of the weight of the substance must be polymeric molecules. In addition, the amount of polymer molecules with the same molecular weight must be less than 50% by weight of the substance.
The European Commission shared its goal of making certain polymers subject to REACH registration in 2019. During a meeting, the Commission had stated that it was working on a proposal to register polymers. The final proposal was expected by 2022.
In 2020, an EU study predicted that 33,000 polymers may require REACH registration (PRR). According to the report by Wook and Peter Fisk Associates (PFA), two consulting firms, the number of polymers on the market was 200,000, of which 100,000 were polymers of low concern (PLC).
EcoMundo accompanies you in all the steps of the REACH registration. For more information, please visit our dedicated REACH service page.
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