DMF: Restriction on the horizon

Dimethylformamide (DMF), more precisely N,N-dimethylformamide (CAS 68-12-2), is an amide of formic acid and is used as a polar organic solvent. The main customers are the manufacturers of artificial leather, but it is also used in particular in the production of polyacrylonitrile fibres, in special varnishes and paints and in plastic coating (polyurethanes). DMF – like DMAc and NMP – is classified as toxic to reproduction by EU harmonisation (category 1b, H360D: may cause harm to the unborn child), and the substance may also irritate the eyes, skin and respiratory tract.

DMF is thus a CMR substance (Carcinogens – Mutagens – Reprotoxic) and was therefore included in the SVHC Candidate List (Substances of Very High Concern) on 19 December 2012 and proposed for inclusion in REACH Annex XIV (Authorisation List) in ECHA’s 5th Recommendation List in February 2014.

In 2014, the Italian REACH authority had already announced to submit a restriction dossier, furthermore, on 25 October 2018, the EU Commission submitted a RMOA (Regulatory Management Option Analysis), which foresees the restriction route as a proven risk mitigation measure for the three aprotic solvents NMP, DMF and DMAc. NMP users have to comply with the established restrictions (compliance with the specified limits) since 9 May 2020. DMF will now follow this path as another aprotic solvent instead of having to go through the time-consuming and cost-intensive REACH authorisation process.

Opinion of RAC and SEAC on the restriction of DMF

ECHA’s Committees for Risk Assessment (RAC) and Socio-Economic Analysis (SEAC) endorsed Italy’s restriction proposal in December 2019 to restrict the use of DMF as a substance or in mixtures at a concentration of 0.3 % or more. The Risk Assessment Committee (RAC) prepares ECHA’s opinions on risks of substances to human health and the environment in the context of the REACH and CLP processes (classification and labelling, restriction, authorisation). SEAC prepares ECHA’s opinions on the socio-economic impacts of possible legislation for substances in the REACH processes. The final decisions are taken by the European Commission.

The RAC established a long-term inhalation exposure limit (DNEL = Derived No Effect Level) for DMF of 6 mg/m3 and a worker-related harmonised DNEL for long-term dermal exposure of 1.1 mg/kg body weight/day. These are still well below the limit values for NMP (14.4 mg/m3 and 4.8 mg/kg/day).

Within three months after receipt of the comments of the RAC and SEAC, which are summarised in a report, the EU Commission prepares a draft amendment of the list of restrictions (REACH Annex XVII). The Commission submits this to the World Trade Organisation (WTO) to ensure that it does not create technical barriers to international trade. It is assisted in this by an advisory committee made up of participants from the Member States.

If no objections are received from the EU Council of Ministers or the European Parliament to the restriction, it will be adopted and published in the EU Official Journal.

Delays due to the pandemic

Due to “Corona”, there were certainly delays in the time schedule, but an inclusion of DMF in REACH Annex XVII via a Commission decision can be expected in the short term. DMF will then be subject to corresponding risk minimisation measures, like NMP.

In 2019, ECHA has produced a guidance document to support companies in the risk management of NMPs. Users of NMPs will find guidance and illustrative examples in this guidance to control exposure when using NMPs and to comply with the restrictions. The general approach described in this guide can also be applied to other aprotic solvents such as DMF and DMAc.

Conclusion

Aprotic solvents are coming under increasing regulatory pressure. Since they are also used in the paint and coatings industry, the limit values must be complied with in the form of DNELs, which will not always be easy to implement, especially for small and medium-sized enterprises. Compliance with the low limit values requires a great deal of technical effort, if not sed in closed systems. In some applications, substitution is not possible.

These restrictions also become particularly relevant for occupational health and safety, because with the entries in REACH Annex XVII, restrictions come into force for the first time that link compliance with EU-wide legally binding limit values (DNEL) to the further use of the substances