Hundreds of children were absent from schools amid fears of lead poisoning in Shanghang County, east China's Fujian Province.

A total of 136 students were absent from the Central Primary School of Jiaoyang Township Thursday and 140 others from the local kindergarten, the primary school's headmaster Zou Chaolin said more students were absent Wednesday.

The county government said that among 72 children who had taken blood tests, four have excessive lead levels in their blood, or more than 100 mg a liter of blood, compared with the normal zero to 100 mg a liter. The other 68 children have 53-100 mg of lead a liter of blood.

Residents in Jiaoyang Township said the excessive levels of lead in blood might be caused by a local battery plant.

The county government has ordered the environmental protection bureau to beef up supervision on the plant.