Four infants in China are now confirmed dead after consuming milk powder tainted with melamine, according to the country's official news agency, Xinhua. Nearly 13,000 children have been hospitalized and another 40,000 have been treated. Melamine, which causes kidney stones and kidney failure, is used to make plastics, fertilizer, and other products, and it is not approved as an ingredient in food. Milk dealers in China allegedly added the nitrogen-rich compound to diluted milk to boost its apparent protein content (C&EN, Sept. 22, page 37). Melamine has been detected in a few samples of liquid milk and at much higher levels in milk powder. The worst contamination was found in milk powder produced by Sanlu. An official investigation revealed that the company knew about the problem but covered it up for months, Xinhua reports. Tian Wenhua, the head of the company, has been charged with producing toxic food and could face life in prison or the death penalty if found guilty. Li Changjiang, head of the country's General Administration of Quality Supervision, Inspection & Guarantee, has resigned.