Big-data based monitoring system helps guarantee food safety for students in Tongren

A staff member prepares lunch for students at No.11 Primary School of Tongren City in southwest China's Guizhou Province, May 21, 2019. Tongren City has established a monitoring system applying new technologies of big data to trace food from farming to dining table, an effort to guarantee food safety for students. (Xinhua/Ou Dongqu)