Medical tests have identified 152 factory workers in south China's Guangdong Province as having suspected mercury poisoning, the local government said Thursday.

The patients all worked for Foshan Electrical and Lighting Co., Ltd in the manufacturing city Foshan, said Yu Zhouhong, deputy head of Gaoming District, where the company is located.

They were all on paid leave to receive further tests at the Guangdong Prevention and Treatment Center for Occupational Diseases, Yu said.

A spokesman with the provincial labor and social security bureau said the workers could claim compensation from their employer once they were diagnosed with mercury poisoning.

The provincial center for the prevention and treatment of occupational diseases collected urine samples from 590 workers of the company's T8 workshop from December 18 to 20, after 23 of them showed excessive mercury levels in tests they paid for themselves.

All six production lines of the workshop used liquid mercury, but some workers seldom took the trouble to wear a mask at work, said the company's human resources manager Lu Ruijin.

Lu said some of the workers showed symptoms such as headaches, hair loss, joint aches and shivers.

Three years into his job, Zhu Wangzhong, a migrant worker from the central Hunan Province, said he feared he was suffering a "fatal disease". "I have a constant headache and have rash on my skin every time I take a shower," said Zhu, 38.

His high urine mercury level suggested he was suffering chronic poisoning.

Guo Yong, a doctor and member of the province's expert panel for occupational illnesses, said mild to moderate cases of mercury poisoning could be cured in about two weeks, if treated in time.

The local government has set up a special team to investigate the case, ensure timely treatment, dispel panic and raise workers' awareness of labor protection.

Three of the production lines have been renovated to use solid, instead of liquid mercury. Renovation is underway at the remaining three lines and is expected to be completed by the end of January.

"Solid mercury is less volatile and therefore less harmful to the workers," said Yang Aichu, an expert for the treatment of occupational diseases based in the provincial capital Guangzhou.

Yang said mercury poisoning is often caused by inhalation of mercury vapor and dust of mercury compounds.

Foshan Electrical and Lighting Co. Ltd is a public company and leading manufacturer of lighting products in China. It employs more than 1,000 people.

(Xinhua News Agency January 7, 2010)