Cases of deadly silicosis top million as estimates revised

China has acknowledged for the first time that it has more than one million cases of the incurable mining disease silicosis, twice the number in the rest of the world.

The Chinese estimate is being released before a national law on occupational diseases comes into effect on May 1. China had previously admitted having 558,000 cases and a cumulative total of 133,000 deaths, but mainland experts say these are only officially registered cases mostly of workers in state-owned enterprises. The new estimate was made by experts at the School of Public Health at Shanghai Medical University.

'We think there are 600,000 additional patients who have worked in private or collective enterprises since the early 1980s,' said Professor Yi Jintai, the head of the public health school.

'Many foreign companies also shifted dangerous jobs to China.'

It has been calculated about 40,000 new cases of silicosis occur every year in China. The new law requires all employers to make workplaces safe and to provide insurance. Peasants who work in private or collective mines are not covered by any insurance. Although the disease is preventable, it is incurable.

Workers in many industries such as mining, sand-blasting, tunnelling, ship-building and ceramics are susceptible to silicosis through inhaling tiny silica dust particles. The particles accumulate in the lung tissue and cause scarring which makes breathing difficult, leading to physical incapacity and often heart attacks. Those with high exposure develop the symptoms within weeks and can die quickly. Sometimes it can take as long as 10 years to become noticeable.