A cohort study was undertaken among workers from four types of industrial factories/mines in south and central China where dusty conditions prevailed, in an effort to evaluate mortality from respiratory diseases, cancer, and other causes among workers exposed to silica (14808607) dusts. Information was gathered from 21 mines (ten tungsten, six copper and iron, and four tin), and eight pottery factories. A followup of workers through December of 1989 revealed 6192 deaths, which was close to that expected based on Chinese national mortality tables. Nearly a six fold increase was noted in deaths from pulmonary heart disease and a 48% excess of mortality was noted from nonmalignant respiratory diseases, primarily because there was a more than 30 fold excess of pneumoconiosis. Pulmonary heart disease and noncancerous respiratory disease rates rose in proportion to dust exposure. Cancer mortality was not increased nor was there an increased risk of lung cancer, except among tin miners. Risks of lung cancer were 22% higher among workers with than without silicosis. The authors conclude that this large cohort of workers in four groups of mines and factories in China has shown that deaths from respiratory disease and its complications have continued at elevated levels through the 1980s, but a major carcinogenic hazard has yet to appear.