Beijing schools have been ordered to check all synthetic running tracks and playgrounds for potential hazards before the start of the new semester on Sept 1.

According to a directive from the city's education commission, all campuses of kindergartens, primary schools and middle schools must be inspected.

"Running tracks or playgrounds that have been found to be toxic should be removed and should be restored through temporary measures before the new semester so that teaching and other campus activities are not affected," the directive said.

The directive, released on Friday, comes after tracks and playgrounds at kindergartens and primary schools in the capital, as well as in other provinces including Anhui, Henan and Jiangsu, were found to emit toxic chemicals that are believed to have caused students to become sick in June.

Students at Beijing No 2 Experimental Elementary School's Baiyunlu campus in Xicheng district reportedly showed symptoms such as bloody noses, dizziness, coughs and rashes after participating in sports and other activities on its synthetic playgrounds. The rubber like surfaces were renovated twice, once in April and again in May.

To handle the situation, the education commissions of several cities and provinces drafted regulations with stricter standards for the construction and monitoring of synthetic surfaces.

The authorities in Beijing requested a suspension of all ongoing construction of campus running tracks and playgrounds. Existing facilities were also tested to find potential problems.

The playgrounds at the Baiyunlu campus were removed on June 17 and the areas were covered with gray water-permeable bricks.

Some residents whose children are enrolled at the school were invited to visit to inspect its environment, Beijing Times reported.

The parents told the newspaper that apart from the new playgrounds being covered with bricks, the school also placed green plants in the corridors of its teaching building and equipped each classroom with two electric fans and an air purifier.