Chang Qing, of China Agricultural University, says he believes that central-government efforts are unlikely to have much impact, and that China will find it difficult to avoid a hard landing in a couple of years' time.

ECONOMIST: The economy just grows and grows

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

According to 2011 research at Nanjing Agricultural University, roughly 10% of all rice sold in China is tainted by cadmium, the result of use of industrial wastewater for irrigation, dumping of industrial waste and overapplication of fertilizer.

WSJ: Cadmium-Tainted Rice Found in Guangzhou