China shuts 9 factories over toxic school tracks scare

China have shut down nine factories making race tracks using recycled toxic materials and detained few people after a number of children fell sick in several schools.

Officials in Cangzhou, North Hebei Province, shut down nine factories and detained "related personnel" on Wednesday, after China Central Television (CCTV) reported that a number of workshops had been using recycled industrial waste to produce materials for the track ovals widely used in schools.

Hebei provincial authorities also vowed to investigate its rubber track producers following the CCTV investigative report that said dozens of companies in Hebei's Baoding and Cangzhou had been using used automobile tires, electrical wires and other plastic or rubber items to produce track oval materials.

These recycled materials are believed to contain toxic chemical substances and heavy metals harmful to human health, the report said.

Following the report, the Cangzhou government set up a special task force composed of industry supervisors and police to inspect all related factories, sealing the equipment, materials and semi-finished products in these workshops, news portal reported.

The CCTV report has added fuel to the ongoing uproar from parents of school children in more than a dozen provinces across the country.

They have been complaining that the pungent smell of newly-built rubber sports fields and tracks are causing the students nosebleeds, headaches and allergies.

Nearly 100 parents of students at Beijing No 2 Experimental School in the capital's Xicheng district gathered outside the school, claiming that the school cheated them in a school-hosted test report that claimed its newly-built track oval met national emission standards, state-run Global Time reported.

The latest test results of an independent institution invited by the parents showed that the content of toxic formaldehyde in the classrooms have all failed national standards, the parents told the Global Times.

The school's principal and parents failed to reach an agreement as of press time, the report said.

Dozens of students at the school suffered from nosebleeds, dizzy spells and coughs after running on the synthetic track oval in Baiyunlu School, the parents said.

Similar incidents have been reported in the past two years in cities that include Guangzhou, Shenzhen, Chengdu and Shenyang.

"We can only call it a 'questionable track' for now, because we haven't received the test results to prove that the track caused all of these problems," Shi Jianhua, who helped draft rules for synthetic materials for track surfaces, told the Global Times on Wednesday.

"But the 'questionable tracks' do contain certain toxic substances, such as methylbenzene which emits a foul smell, and the smell surfaces in high temperatures," Shi said.

Some samples contain methylbenzene and xylene, Shi said many 'questionable tracks' were produced by small uncertified workshops, and they won the contract by offering lower prices.