Wu Houhua is no longer able to work after five years of working in a gem processing factory in Huizhou, Guangdong province.

The 38-year-old migrant worker from Sichuan province was recently diagnosed with silicosis disease, a chronic lung disease caused by his work at the factory.

"The disease is caused by the inhalation of silica dust over long periods of time working in a gem-processing plant," said Zhang Donghui, a lung disease expert at the Guangdong Provincial Prevention and Treatment Center for Occupational Diseases.

The number of patients diagnosed with dust-related diseases in the province has risen steadily in recent years, Zhang said.

Nearly 400 cases of dust-related diseases has been reported in the province since 2005, Zhang said.

"Most cases were reported in the prosperous Pearl River Delta region's gem processing and accessories plants, which produce large amounts of dust," Zhang said.

Additionally, workers' complaints related to dust-related lung diseases have dramatically increased, said Wen Xianzhong, an official of the Guangdong provincial health department.

Wen was in Zhuhai yesterday, taking part in a province-wide campaign of inspection and prevention against occupational diseases, which was launched by the provincial health authority.

The campaign is part of a national move by the State Administration of Work Safety, Ministry of Health, Ministry of Human Resources and Social Security and the All China Federation of Trade Unions to tackle problems of dust-related diseases, Wen said.

"Industries which produce high levels of dust, especially the gem-processing plants, will be targeted," Wen told China Daily.

A new diagnosis standard of occupational diseases, such as dust-related lung disease, will be implemented later this year, said Huang Ruiying, a press official with the Guangdong Provincial Prevention and Treatment Center for Occupational Diseases.

"We will use the new standard to identify the workplaces connected to occupational diseases," Huang said.

In the past, workers in coal mines were vulnerable to dust-related diseases, Huang said.

"However, more workers have jobs in the diamond, shoe and garment industries. They also easily develop lung diseases as they pay less attention to dust emissions in factories," Huang told China Daily.

(China Daily August 21, 2009)