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Chromium trioxide and the health risks

Chromium-6 is a metal added to paint because of its ability to protect against rust. In dry paint, chromium-6 is fixed and does not pose a health risk. However, when the painted surface is worked or when new paint is applied, chromium-6 can enter the body via airborne dust particles. Long-term or frequent exposure to the substance can be harmful to our health.


NS employees have performed work on trains in the past, but it is as yet unclear whether they were exposed to paint containing chromium-6 in the conduct of these activities. Together with the Institute of Risk Assessment Sciences (IRAS), the National Institute for Public Health and the Environment (RIVM) is investigating whether current or former NS employees have been exposed to chromium-6, and under which working conditions.

In solid form, chromium-6 is not harmful to people or the environment. Chromium-6 is only harmful in vapour or dust form and in cases of long-term and/or frequent exposure. Our bodies can convert low levels of chromium-6 to the harmless compound chromium-3. On the RIVM website you can find more information about what it is, its applications and what the health risks are.