But researchers at Nanjing Agricultural University found that 10% of China's rice crop is contaminated with the metal.

WSJ: Review & Outlook: China's Toxic Rice Bowl

According to 2011 research by Nanjing Agricultural University, roughly 10% of all rice sold in China is tainted by cadmium.

WSJ: Cadmium-Tainted Rice Found in Guangzhou

Based on a survey conducted in 2007 and 2008, researchers at Nanjing Agricultural University estimated that roughly 10% of the country's rice supplies contained excessive levels of the poisonous metal.

WSJ: China Seeks to Calm Anxiety Over Rice