BEIJING • The Chinese authorities are investigating playing fields at some of Beijing's top primary schools after children reportedly fell sick following exposure to artificial turf.

Youngsters have suffered nose bleeds and allergic reactions after using the running tracks, in the latest health scare to rock a country where safety standards are a big concern.

The news comes less than two months after reports that hundreds of students had fallen ill elsewhere in China because of their school's proximity to shuttered chemical plants.

The Beijing probe, which began last week, sparked a wave of anxiety online, with hundreds questioning the country's commitment to protecting one of its most valuable assets: its youth.

Toxic air and poisoned food already create dilemmas for Chinese concerned about their children's health. Frequent reports of early onset cancer and respiratory ailments create a climate of fear for parents, many of whom who have only one child, thanks to China's once strict birth control policies.

The Beijing cases are particularly unsettling because they have occurred at schools attended by children of the capital's well-to-do. "If Beijing is like this, it's even harder to imagine those campus fields in other cities," a netizen commented.

In April, news outlets reported that almost 500 students were sickened after a top secondary school relocated to a site close to decommissioned chemicals factories.

An undisclosed number of young people were diagnosed with leukaemia and lymphoma, both diseases often linked to pollution.

In Beijing, the authorities have vowed to deal with the issue and plan to release a report on the materials used to build the tracks next week.

AGENCE FRANCE-PRESSE