ProRail is jeopardising workers’ health by inaction over quartz dust: Zembla

Photo: Niels Pluto
Photo: Niels Pluto

Railway workers have been exposed to harmful quartz dust from track ballast for a decade or more but ProRail and contractors have consistently ignored the outcomes of reports they commissioned, investigative news programme Zembla claimed on Thursday.

Quartz track ballast is made up of stones which serve as a bed for rail tracks and provide drainage and strength for heavy loads carried by trains. Work on the ballast can result in quartz dust being released from the stones, which can cause lung cancer.

ProRail had been advised more than once to use quartz free or quartz reduced track ballast but has failed to act, Zembla said. That means the railway operator is not complying with its legal duty of care.

Experts are calling the very fine quartz dust ‘a silent killer’ because it penetrates deeply into the lungs and can result in serious lung diseases years after having been exposed. Some railway staff work with the stones on a daily basis, often standing in great clouds of dust without wearing masks, as footage shown by Zembla attests.

ProRail carried out its own investigations into the extent workers were exposed to quartz dust in 2010, 2017 and 2020 but did not share the findings – that exposure to quartz dust was greater than legally allowed and the stones should be replaced –  with inspectors.

‘The fact that this has been going on for so long means it is probable that people have become ill when this could have been prevented,’ occupational health and safety expert Tamara Onos told Zembla.

Quartz free ballast must be replaced, experts said, because workers often don’t wear protective gear and other measures such as keeping the stones wet, are impractical.


In a reaction ProRail said safety measures had to be complied with and that it is not breaking the law because Dutch research institute TNO is already looking into alternative ballast material.

However, Zembla also had access to a TNO report which states that ProRail is ‘not complying with the Arbo (health and safety) law’ because of too high concentrations of quartz dust.

‘They are spending money on investigating things they are already aware of. They would do better to spend that money on protecting workers,’ Onos said.

Het Stofspoor (the dust trail) will be broadcast on Thursday at 8.25 pm on NPO3.

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