BEIJING - China's quality watchdog said Friday that the latest checks by testing organizations did not find excessive levels of aflatoxin in milk products made by Chinese dairies.

The special checks were launched after the General Administration of Quality Supervision, Inspection and Quarantine (AQSIQ) reported on December 23 that two batches of milk products made by two separate domestic dairies, including heavyweight Mengniu Dairy Group, were found to contain high levels of the cancer-causing toxin.

A brief statement on the government agency's website Friday said the checks have covered major makers, including Mengniu, Yili Industrial Group, Bright Dairy, and Sanyuan Food.

An AQSIQ official said earlier the toxin had originated from cows eating mildewed feed, citing reviews by experts. The toxin would disappear if the animals stop eating the rotten feed, the official said.

Aflatoxin is produced by a fungus that commonly grows on crops such as grain and peanuts. High levels of the toxin may lead to cancer in some animals.