Users of NMP – how to comply with the restriction


From 9 May 2020, 1-methyl-2-pyrrolidone, also known as NMP, must not be placed on the EU market, nor used, on its own or in mixtures, unless certain conditions are met. The substance is widely used as a solvent, for example in the petrochemical, surface treatment and pharmaceutical industries. ECHA Newsletter explains what this restriction means for companies.

What is NMP?

NMP is used in high volumes as a solvent and a medium for surface deposition when producing batteries, semiconductors, fibres, pharmaceuticals and wire coatings. The chemical has a harmonised classification indicating that it may cause damage to the unborn child, serious eye and skin irritation and respiratory irritation.

Due to its reproductive toxicity and high volumes, the European Commission added the substance to the REACH restriction list in April 2018. The restriction enters into force in May 2020 bringing in strict limitations for its use. But there is an exception for NMP uses in wire coatings, where the restriction will apply from 9 May 2024.

Strict conditions for its use

The restriction does not mean that NMP can no longer be used on the EU market but it places strict conditions on its use.

If the substance is produced or used in concentrations of 0.3 % or more, manufacturers, importers and downstream users must put appropriate risk management measures and operational conditions in place to protect their workers from any exposure.

This should be done by using the agreed derived no-effect levels (DNELs) in the relevant chemical safety reports and safety data sheets. The DNELs refer to a level of exposure to a substance below which no negative health effects are expected. For NMP, the levels for worker exposure are 14.4 mg/m3 if inhaled and 4.8 mg/kg/day if skin is exposed. Having the DNELs as part of the restriction make the levels binding across the EU.

A manufacturer’s perspective

The NMP restriction affects the whole supply chain from the substance manufacturer to downstream users, who can vary from knowledgeable chemical companies to industrial users operating outside of the chemical industry.

According to Jens-Olaf Eichler-Haeske, Global Product Stewardship Manager at BASF SE, their company is already implementing high occupational safety and process safety standards to protect their workers from the exposure to NMP. “BASF SE and other NMP manufacturers have already put in place strictly controlled manufacturing conditions which mean that we, in practice, already comply with the restriction,” he explains.

Since it is the manufacturers’ role under REACH to evaluate the use of a substance and to advise on safe use conditions, BASF SE communicates the information needed to comply with the restriction to their customers as part of extended safety data sheets (eSDSs). “Often, the problem is that downstream users outside the chemical industry may not know how to read the exposure scenarios and the information on safe use found in the eSDSs. They may face difficulties in extracting the information and translating it into real risk management measures,” Dr Eichler-Haeske points out.

This is where ECHA’s NMP guideline can help by providing answers and examples. “An NMP downstream user should start by identifying the exposure scenario that fits to the use. For translating the advice given in the eSDSs, take a look in the annex to the guideline, which provides pictures of safe use for some standard uses of NMP. By following the instructions of the eSDSs correctly, you can make sure that you use NMP under safe conditions and in compliance with the restriction,” Dr Eichler-Haeske says.

Exemption for the wire coating sector

The wire winding sector is highly dependent on NMP as the enamel they use when coating wires to form protective electrical insulation, normally contains NMP.

“The restriction has clearly increased awareness about the consequences that using NMP-containing enamels has on our industry,” says Andreas Levermann, Managing Director of SHWire.

The restriction for the wire winding sector enters into force in May 2024, but it has already been discussed in depth by the industry association. Many of the companies using enamels that contain NMP are already working hard to ensure workers’ safety, but they may still need to look into their risk management measures to ensure they fully comply with the restriction.

“Each company has a series of choices to make related to exhaust ventilation, limitations for possible exposure times, and suitable respiratory equipment to mention some,” Dr Levermann explains.

As the amount of NMP in an enamel depends on the wire properties, the restriction will not have a big impact on the material and the solvent itself. Preparations are still needed before the restriction starts to apply. “The most significant impact concerned the use of new types of better-controlled ovens and enamelling machines, which led companies to modernise their machines, which, of course, required high levels of investment,” Dr Levermann adds.

The ECHA guideline has given useful advice and support for the wire winding sector. “You should not only pay attention to the technical part of the guideline. Also the introductory chapters that explain, for example, the limits and DNELs can help you understand what impact the restriction has on our everyday work,” Dr Levermann concludes.

ECHA, 13 February 2020