A view of the new campus of Changzhou Foreign Languages School near a toxic site in Changzhou city, East China's Jiangsu province, April 18, 2016.[Photo/IC]

Health tests show that at least 522 students have developed medical conditions, claimed parents of students at Changzhou Foreign Languages School in Jiangsu province on Wednesday.

But the school refuted the report, claiming indoor air quality, soil and groundwater meet national standards and cited a Changzhou health bureau's report to show that only 133 among 597 students showed abnormal conditions.

A recent report by China Central Television put the Changzhou school in hot water after it ran a story that claimed that as many as 500 students have been reportedly diagnosed with different illnesses, including cancer, caused by toxic groundwater and soil next to the school.

About 10 parents collected health reports of 683 students on Tuesday and they found that 522 students displayed health problems after their checks until earlier Wednesday, The Beijing News reported.

Parents said that the health problems of about 90 percent students were thyroid nodules, enlarged lymph nodes or nodules. They said some students were healthy in their January reports, but later reports showed they were ill.

Changzhou health bureau's report said that medical experts analyzed the health reports of students provided by parents earlier and they said that abnormal indictors need to be specified due to individual situations.

Experts said thyroid nodules might be caused by taking too much iodine and high psychological pressure, and enlarged lymph nodes might be caused by infections of teeth and tonsils, and parasites.

Changzhou Foreign Languages School moved to its new campus that was just next to the land of former three chemical companies in September last year, and about three months later parents said they found their children getting sick, such as developing lymphoma, leukemia and other blood abnormalities.

Students said they smelt foul air in the school while the land of former chemical companies was under restoration.

Workers of the chemical companies said that some toxic materials were buried under the ground and some wastewater was also discharged directly into nearby channels without disposal in the past.

The chemical companies had moved to other places by 2011, but the land restoration work started late last year, and according to a former planner of the city government, the work should start before the school moved there.

An environment expert Chen Nengchang from Guangdong province told media that the restoration work of the land with toxic materials would cause serious secondary pollution to environment.

After the CCTV report, the ministries of education and environmental protection have paid close attention to the case. The education ministry sent an inspection team to Changzhou.

A joint investigation group formed of officials from environmental protection ministry and Jiangsu provincial government has arrived in Changzhou on Tuesday to take samples of the land of former chemical plants.

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