Sunday, March 29, 2009 

A highly radioactive lead ball that vanished from a factory in China has been traced to a Shaanxi Province metalworks. The ball was removed during the dismantling of a factory in Tongchuan City.

The component vanished on Monday when workers broke up the Shaanxi Qinling Cement Company’s 53-year-old factory for not meeting environmental standards. The ball contains the radioactive isotope caesium-137 and was part of a scale to gauge the quantity of goods passing on a conveyor belt.

Caesium-137 emits gamma rays which can damage the nervous system, lead to infertility and be fatal. It is formed by nuclear fission.

Investigators thought the missing part had most likely been accidentally mixed in with scrap and sold on to metalworkers. On Friday, high levels of radiation were detected at the Xingbao Steel and Iron Company Ltd. The Weinan City business had bought eight truckloads of scrap metal from the cement factory.

Further investigations determined that the ball had been melted down in the No. 6 smelter at Xingbao’s factory. Slag from the smelter was found to be radioactive, and technicians are now working to clean the toxic slag and the smelter. Xi’an-based Northwest Institute of Nuclear Technology researcher Wang Xuhui stated that the steel products themselves were safe, as the caesium-137 had mostly ended up in the slag.