OSAKA -- City officials on Wednesday tested soil and water for dioxin around two man-made islands in Osaka Bay that are the proposed sites of the 2008 Summer Olympics and Olympian Village.The tests were conducted in areas surrounding Maishima and Yumeshima, which were created using the soil and ash from a city waste incinerator suspected of containing the cancer-causing substance. The test results will be released at the end of January.Officials took samples of water and soil 30 meters offshore from Maishima. They also collected surface and subsurface soil from the island for testing. Near Yumeshima, which is still undergoing reclamation, officials collected sewage water flowing from the city into the bay.The city has already canceled a part of its initial Olympic-related construction plans, including the main stadium and an indoor pool, because of concerns over toxic substances at the sites.City officials said that although all precautions were taken to prevent environmental damage, the tests were held to doubly safeguard the islands' future development.