In total 131 primary and middle school students in the county of Jingyang, northwest China's Shaanxi Province, were reportedly poisoned by ricin early yesterday.
A source at Xi'an Xijing Hospital said they have received their first student patient on Wednesday night who has been poisoned after eating castor bean.
The castor bean can be poisonous when eaten raw or even when cooked. The poison causes nausea, vomiting and diarrhea.
Li Xiaojing, head of the county, said all the students have been involved in planting ricin organized by the provincial youth working commission and a local company in late March. The illness didn't become evident until Wednesday night.
By press time all the students are receiving medical treatment in hospital.
Other students who participated in the activity have received checkups and been given the all clear.
(Xinhua News Agency April 7, 2006)