For years, battery factories in Hungary may have emitted up to 150 times more teratogenic solvents than in Germany

Péter Magyar would investigate pollution from battery factories; according to Viktor Orbán, environmental regulations in Hungary are stricter than in Germany.

“If you compare, say, a German investment in the automotive industry with a Hungarian one, the environmental regulations governing these investments are stricter in Hungary than in Germany,” said Viktor Orbán in 2023. He was mistaken. This is certainly the case with N-methyl-2-pyrrolidone (NMP), a solvent with teratogenic effects that is also used in the manufacture of electric car batteries.

In Germany, the Chinese giant CATL has been manufacturing lithium-ion batteries since 2022. During production, NMP is released into the air from certain equipment. This substance can cause serious health damage, so its emissions must be limited. In accordance with the German Clean Air Act, the competent Thuringian state authority has set a limit of 1 milligram per cubic metre for the amount of NMP that production units at the CATL factory are permitted to release into the air.

In Hungary, however, the limits set out in CATL’s licence are quite different. The giant corporation has also built a battery factory in Debrecen, parts of which are already operational. The Hajdú-Bihar County Government Office issued the CATL factory’s permit in 2023, with significantly higher NMP limit values. For some production lines, a limit of 1 mg/cubic metre was set, similar to that in Germany, whilst for others a limit of 25 mg/cubic metre was stipulated, which is 25 times the level permitted at the German plant.

The situation was even worse in Göd and Komárom.

150 times the emission limit

In the case of the Samsung factory in Göd, the Pest County Government Office set the maximum NMP emission limit at 150 mg/cubic metre. The situation was similar at the battery factory and NMP processing plant in Komárom, which belongs to the Korean SK Group: the Komárom-Esztergom County Government Office authorised an emission limit of 150 mg/cubic metre.

In other words, the production units at the Göd and Komárom plants were permitted to emit 150 times more NMP than the German threshold.

In the case of the Samsung factory in Göd, the authorities tightened the limit to around 3 mg/m³ in December 2023. In the case of the Komárom factory, however, the situation remained unchanged until as late as 2025. In 2024, Greenpeace sent an official letter to the Komárom-Esztergom County Government Office demanding that the plant’s environmental permit be tightened; eventually, in February 2025, the authorities reduced the NMP limit to 1.7 mg/m³.

In the case of the CATL plant in Debrecen, the tightening of the limit to 1 mg/m³ took place even later, in November 2025. There was, however, a slight twist to the story: the text of the permit reveals that CATL is not, after all, establishing the so-called NMP distillation unit—which produces the highest emissions—within the factory itself, as “technology capable of meeting the stricter limit is still under development”. In other words, NMP recovery will be outsourced, meaning emissions will occur elsewhere.

EU legislation is ambiguous, which may cause complications in national regulations, an expert who requested anonymity told Átlátszó. EU law regulates chemical emissions on two fronts: from a biological risk perspective and in relation to specific technologies. Thus, in Hungary, separate limit values have been set in various regulations for volatile organic compounds – a group which includes NMP – as well as for substances that impair reproduction – a group which also includes NMP. According to our expert, both interpretations could be derived from EU law, but Greenpeace clearly found the authorities’ practice to be in breach of the law.

The Samsung factory in Göd uses 22,000 tonnes of solvent a year, whilst the Debrecen factory has been granted a licence to use nearly 18,000 tonnes of NMP solvent, meaning we are talking about enormous quantities.

The Ministry has taken action

The tightening of official permits may have been influenced by the fact that in autumn 2024, the Ministry of Energy adopted stricter regulations and generally reduced the NMP emission limit to 1 mg/cubic metre in Hungary. This is in line with German regulations, yet contrary to Viktor Orbán’s claim, it is no stricter than those. Furthermore, plants already in operation and those currently undergoing the licensing process have been granted an exemption from compliance – the former until 2028, and the latter until 2027.

During his tour of the country, Péter Magyar promised at an event in Göd in March that the Tisza government would require battery factories to strictly comply with Hungarian and European legislation. The party leader also promised to establish a national battery industry regulatory authority, as well as to investigate cases of labour and environmental pollution at battery factories. Péter Magyar told Átlátszó that the companies operating the plants must be held to account, and that the state and the authorities can also be held responsible if they failed to comply with or enforce the legal requirements.

Átlátszó reported that NMP was detected in the well water in Göd in 2022. We also revealed that 88 tonnes of NMP were released into the air in Göd over the past few years. In January, 24.hu reported that NMP had been found in a groundwater monitoring well next to Dongwha’s solvent recycling plant in Sóskút during a sampling exercise in 2023. Two weeks ago, we learnt that a Chinese company was planning to set up an NMP recycling plant in Kunmadaras, after its plans in Heves were thwarted by local protests.

However, Greenpeace recently announced that, during their latest measurements in March this year, they had found no NMP contamination exceeding limit values or posing a significant health risk in certain residential wells in Göd, Komárom, Sóskút and nearby Tárnok. However, due to the extremely small number of samples (ten altogether), no far-reaching conclusions can be drawn from the analysis, only that the water from the ten selected domestic wells was not contaminated with NMP. Pollution is usually monitored using monitoring wells located on or near industrial sites; however, these are not accessible to members of the public or the local population.

Orsolya Fülöp

Cover image: Átlátszó.