Objective To evaluate the effects of cemented carbide dust exposure on pulmonary function of workers and to provide a scientific basis for making related occupational health technical specifications.
Methods In three cemented carbide production enterprises of Hunan Province, 272 tungsten carbide and cobalt carbide dust exposed workers (dust exposure group) and 168 control workers (control group) were recruited to conduct a survey including questionnaire, lung function test, and occupational health field investigation.
Results The disqualified rate of 8-hour time weighted average concentration of tungsten carbide and cobalt carbide was 6.3% (8/127). The report rates of cough, sputum, chest tightness, short of breath, and breathing difficulties in the dust exposure group were 13.24%, 12.50%, 12.50%, 9.19%, and 8.82%, respectively, significantly higher than those in the control group (P < 0.05). The dust exposure group's forced vital capacity (FVC), first second forced expiratory volume (FEV1), peak expiratory flow (PEF), measured value/expected value of forced expiratory flow 25% (FEF25) were (98.69±11.72)%, (93.39±12.22)%, (92.59±17.19)%, and (90.22±21.98)%, respectively, significantly lower than the corresponding values of the control group(105.35±11.59)%, (99.15±11.28)%, (99.49±17.83)%, and (96.45±19.24)%, respectively (P < 0.01). The workers at work stations with either excessive or qualified dust concentrations showed no difference in lung function indices (P > 0.05).
Conclusion Cemented carbide production dust exposure could induce obvious damage to workers' respiratory system such as reduced lung ventilation function and small airway ventilation function.
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