According to The Economist, the most neglected threat to public health in China is toxic soil, which contains elevated levels of heavy metals including lead and arsenic. In 2014 the Chinese government published a national soil survey which showed 250,000 square kilometers of farmland was contaminated by organic and inorganic chemical pollutants and by metals such as lead, cadmium and arsenic. Sewage irrigation, fertilizers and pesticides are also culprits throughout the country. Many people are unaware that hemp labeled as being from Europe is often grown in China and processed in Europe.