Thousands of painters, welders and other NS maintenance personnel may have been exposed to the harmful substance chromium-6 over the past fifty years.

    The rail company has long failed to comply with regulations for protecting its employees against the harmful effects of the toxic and carcinogenic substance. NS did not medically examine employees, did not inform them, and did not adequately supervise protective measures.

    This is the conclusion of RIVM after research into the use of chromium-6 in NS workshops. The study was requested by NS in 2015. The institute investigated the use of the substance in the rail company from 1970 to 2020.

    Cancer and lung diseases

    Chromium-6 is very harmful. It can cause cancers, serious lung diseases and other conditions. Chromium-6 was used by NS, but also by defense and airlines such as KLM against rust formation. In the 1970s and 1980s, primers containing chromium-6 were used on virtually all steel train components. Its application has since been phased out.

    It is not known how many NS employees have been exposed to chromium-6 and how many have become ill. NS does not have any personnel data older than the statutory retention period of seven years.

    It had been known within NS since the late 1970s that chromium-6 entailed serious health risks. In the 1980s, the company would have already decided not to use paint with chromium-6 anymore. That information was not sufficiently shared with departments where sanding and welding was done on older trains that had already been coated with the chromium-6-containing paint. Employees inhaled the harmful substances.

    “NS employees are exposed to more chromium-6 than if NS had complied with the applicable regulations,” said the RIVM researchers. For example, employees have run an unnecessarily high risk of becoming ill.


    Wouter Koolmees, president of NS, apologized this morning for the negligence of the rail company and for the suffering and uncertainty among current and former employees. The company presented a financial arrangement for victims and surviving relatives. This is similar to the arrangement that the Ministry of Defense made a few years ago with employees who had become ill due to chromium-6. This involved one-off and illness-related amounts of between 5,000 and 40,000 euros. KLM also announced a scheme for maintenance employees who have worked with chromium-6 last month.

    The RIVM investigation and the financial arrangement announced by NS on Tuesday are separate from the case involving the use of chromium-6 at NS subsidiary NedTrain in Tilburg. There, benefit recipients were required to work on museum trains that – as it turned out – had been painted with a primer containing chromium-6. Eight hundred people there may have been in contact with the harmful substance.