"Toxic School Uniform" has become one of the most popular topics this week on Weibo, the Chinese equivalent of Twitter. Tweets about this topic are sent out almost every minute. The hottest one is an interview of an elementary student, who said that the toxic uniform is to blame for all his low grades.

On Feb.18, Xinhua News Agency published an article about the recall of more than 26,000 school uniforms from 21 schools in Shanghai.

"In a recent quality inspection campaign, aromatic amine dye, which can cause cancer, was detected in one batch of student uniform produced in July 2012 by Shanghai Ouxia Garment company…six batches of the company's clothes products were substandard… the company has been one of a number of producers of school uniforms in Shanghai for five years," the report said.

South China Morning Post published a news blog commenting about toxic school uniform the next day.

"Because education authorities require that each school uniform must not cost more than 250 yuan, most large garment manufacturers are not willing to make them… Consequently, the job is left to smaller factories which often fail to meet quality standards," that report said.

The Chinese New Year holiday is nearing an end, meaning students are returning to school on March 1. As is tradition, schools will distribute new uniforms before classes. Wearing school uniforms every day is a tradition in most of China's schools.

Parents from other provinces in China questioned the quality of their own children's garments.

"My kid's uniform cost 50 yuan, there is no trademark or any certification from garment maker. I never doubted about quality of uniform before Shanghai's toxic uniforms," said Wang, a parent of a student from elementary in Xi'an, according to a Chinese media, Sina.

China Daily published the latest investigation on Feb. 20 into the sources of school uniforms found to contain cancer-causing dyes.

"The disciplinary inspection department of Shanghai Pudong Education Bureau said on Tuesday it has started to investigate the case, including the purchasing and sales of toxic clothing materials," the Daily said.

Investigations will continue to inspect how Shanghai schools buy uniforms.