BEIJING - China's top food watchdog Friday ordered a national food safety overhaul of school dining halls in spring 2012, as the country increases its efforts to prevent food poisoning in schools.

The State Food and Drug Administration issued a circular asking provincial-level authorities to check food safety in school canteens, especially in rural primary and middle schools.

The key aspects to be scrutinized include catering licensing, hygiene, food processing, materials storage, purchase records, sterilization and water use.

The circular stressed that any elements posing potential threats to food safety should be handled appropriately, calling for every measure to prevent food poisoning.

China reported 46 food poisoning incidents during the period of October to December last year. Nine of these stemmed from school canteens and sickened 688 people, according to latest health ministry figures.

In a statement publicized last week, the Ministry of Health cited microorganism contamination and inappropriately-treated snap beans as two major causes of school food poisoning incidents during the period.