The Shanghai Municipal Bureau of Quality and Technical Supervision has announced that a cancer causing aromatic amine dye has been found in school uniforms manufactured in July last year by the Ouxia garment company.

The eastern Chinese city’s quality watchdog said six batches of the apparel firm’s school uniforms were found to be substandard.

Subsequently, the education authorities in the Pudong New Area of Shanghai have asked 21 schools that had procured uniforms from Ouxia to ask its students to stop wearing their uniforms, pending further quality examinations.

Meanwhile, Ouxia, which sells about 15,000 school uniforms annually for primary and middle schools, has stopped production, Chinese state-run agency Xinhua reported.