Heavy metal pollution contaminates 12 million tons of food crops a year, and the lead content of 30% of rice surpasses the health limit. A report made public in April of 2014 by the ministry of environmental protection and the ministry of national land resources showed that nationally, one fifth of arable land has been polluted.
Hunan province has been struggling with ways to reduce cadmium contamination of rice for many years. In August, 2014, the province spread lime in 760000 mu of rice fields in an attempt to reduce absorption of heavy metals by the soil and the water in the fields. This is because the soil in Hunan is acidic. The province has also tried the variety + irrigation + pH (VIP) method. However, water is scarce and there is no other rice variety available in Hunan. The only way is the manipulate the pH of the soil. This turns out to be ineffective in reducing cadmium contamination of Hunan rice. The cadmium laced rice found in Guangdong province all came from Hunan.