Foshan has decided to shut down a number of quartz sand processing plants before the end of next year. The city's work safety supervision bureau will finalize the list of those factories by August. The latest statistics released by the Foshan Health Bureau indicate that the pneumoconiosis, better known as the black lung disease, was the leading occupational disease killer in the city last year. The majority of the patients felt sick because they lived in proximity to factories manufacturing porcelain, jewelry and quartz sand.