Economy 25 February 2026, 8:55am

In previous years, the Samsung SDI factory in Göd and the SK plant in Komárom were in the news primarily due to the improper handling and release of the fetus-damaging solvent NMP into the environment. However, the current, more comprehensive Hungarian research focused on the condition of the Danube, where researchers searched for perfluoroalkyl and polyfluoroalkyl substances, or PFAS compounds. These substances are aptly called "forever chemicals" in common parlance because they are extremely resistant: due to the strong chemical bond between carbon and fluorine, they hardly decompose in nature. While the textile industry uses long-chain versions because of their water-repellent properties, in battery manufacturing, short-chain PFAS are added to electrolytes to increase stability.

Between July 2024 and January 2025, researchers took a total of 96 samples from the water and sediment of the Danube at eight different locations. The study covered the areas surrounding the Komárom battery factory, the Dunaföldvár paper mill, the Százhalombatta oil refinery, and the Vác area, which receives wastewater from the Göd factory.

The results showed a clear correlation with industrial activity.

The concentration of pollutants was highest directly at the emission points, decreasing by 30–40% as it moved away from the river. The most serious pollution was measured near the battery factory in Komárom and the paper mill in Dunaföldvár, where the concentration of chemicals in the sediment was sometimes a hundred times higher than the values measured in the water.

The problem is exacerbated by the fact that the short-chain compounds used in the battery industry are less likely to bind to sediments, making it easier for them to pass through the protective barrier of shore-filtered wells. Professor Emeritus Gyula Záray, one of the authors of the study, emphasized that

since Budapest and many towns along the Danube obtain their drinking water through coastal filtration, it is crucial to determine whether current technology is capable of filtering out these substances.

The situation is further complicated by the fact that during floods, contaminated sediment accumulated at the bottom of the riverbed can be stirred up, which remobilizes the toxic substances.

The measurement method used in the study (measurement of adsorbable organic fluorine compounds, or AOF) provided a cost-effective picture of total pollution. However, accurately identifying individual compounds would be extremely costly and difficult due to the diversity of the PFAS family. According to the expert, the fact that factories often treat the additives they use as trade secrets is a serious problem. As a result, authorities and water utilities do not know exactly what to look for or filter out.

The results of the research are particularly relevant in light of the new, stricter EU drinking water directive that came into force in January 2024. If it is proven that compounds from battery factories pass through the filter layers, rapid intervention may be necessary.

More effective water purification technologies, such as activated carbon or reverse osmosis, may be introduced to protect the drinking water of the population.

According to Gyula Záray, these defense developments should be carried out with the same intensity as industrial development itself.

Cover photo (for illustration purposes only): Getty Images