In the last five years, Japan has spent over half a billion dollars to clean up the World War II era chemical weapons it left behind in China. The government of China insists that there are still two million chemical weapons (mostly bombs or artillery and mortar shells containing mustard, phosgene and lewisite) lying about, many of them in unknown locations. The chemical agents are largely the same ones developed during World War I. The Japanese admit to running the chemical weapons program in China during World War II, but say there are only about 700,000 chemical weapons to be recovered. The Japanese buried most of their chemical weapons at the end of World War II, or left them in underground bunkers where they were stored. The Chinese just ignored them for many decades. But over the years, the locations were either clearly marked or, as happened two months ago, a farmer in northern China, digging in the courtyard of his house, found some 500 chemical bombs dumped in a 43 square foot pit in 1945. At the time, the area was occupied by a Japanese army unit. Japan sent a technical team to safely remove the bombs. 

Japan is spending nearly $200 million this year for such operations. By the terms of the United Nations Chemical Weapons Convention, all countries with chemical weapons are supposed to dispose of them by 2007. But Japans problem is that it does not know where all its World War II era chemical weapons were left in China at the end of the war. The Chinese, however, believe that Chinese farmers and builders will be bumping into these lost weapons for decades to come, and wants Japan to continue paying for the removal of these weapons. Some of the chemicals are still lethal, if the containers they are in have not been breached. This has been the experience in Europe, where chemical shells from 1917-18 are still be unearthed, and still injuring people.