Chinese authorities have shut down nine factories and detained some executives after reports that toxic industrial waste was used to make running tracks widely used at schools, official media said Thursday.

Smelly synthetic sports fields and athletics circuits, along with students falling sick from exposure to them, have regularly made headlines in China in recent years.

A rooftop running track in China. Photo: China News.

Parents of pupils at an elite elementary school in Beijing protested this month saying that their children suffered from nose bleeds and allergic reactions after using running tracks, the latest health scare in a country where safety standards are frequently compromised for profits.

State broadcaster China Central Television (CCTV) reported this week that dozens of companies in Cangzhou and Baoding in the northern province of Hebei had been producing running track materials from recycled industrial waste such as automobile tyres and electrical wires, which were believed to contain toxic chemical substances and heavy metals.

The Cangzhou government set up an investigation team and local authorities have shut down nine plants, sealing their machines, materials and semi-finished products and putting “related personnel” in custody, said, the Hebei provincial government’s news portal, on Thursday.

Running track being demolished in Beijing. Photo: Screenshot from China News.

Polluted air and contaminated food regularly worry Chinese parents, many of whom who have only one child due to the country’s family planning policies.

Incidents in Beijing are seen as particularly unsettling as many Chinese believe regulations are more strictly enforced in the capital than elsewhere.

In April, reports said almost 500 students were sickened after a top middle school in the eastern city of Changzhou relocated to a site close to decommissioned chemical factories.

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