The number

12 million metric tons

Soil in 36,000 hectares of farmland in China contains more than the standard amount of heavy metals, resulting in 12 million metric tons of contaminated grain and direct economic losses of 20 billion yuan ($3.2 billion) every year, according to the Ministry of Environmental Protection. China's soil contamination is more severe than in other countries, and the deteriorating situation may last for 30 years, said Pan Genxing, a professor at Nanjing Agricultural University.