Analysis of the incidence of pneumoconiosis

Abstract

Objective To investigate the level of pneumoconiosis incidence at present. Methods A retrospective study of pneumoconiosis inci dence in 11 factories and mines and 1 area(Liaoning Province) by unified design was carried out.Based on exposure time by year and life table,the cumulative pneumoconiosis incidence of 30 year length of service was calculated.Average dust concentration and fre e SiO2 content in worksite by year were obtained by cross section sampling and weighted rock composition resampling analysis. Results The detected rate of pneumoconiosis in Liaoning Province in 1950s was 6.29% and decreased to 0.83% in 1990s.The cumulative incid ence of 30 year length of service was 0.007 3～0.157 5 in 11 factories and mines .There was a close relation between the incidence and dust concentration,free Si O2 content.The cumulative incidences were 0.113 9～0.157 5 in gold and copper m ine workers,while 0.032 9～0.082 7 in molybdenum mine,coalmine(machine mining) a nd fire-proof material factory,and 0.007 3～0.010 5 in iron mine and coal mine (explosion mining) with lower SiO2 content and dust concentration. Conclusion The hazards of pneumoconiosis are still serio us in China at present.To accelerate legislation and to work out a plan for solv ing pneumoconiosis are suggested.