OBJECTIVE: To explore the effects of cumulative noise exposure(CNE) on the intima-media thickness(IMT) of carotid artery in steel workers. METHODS: A cluster random sampling method was used to select 1 437 noise exposed workers in a steel company as study subjects. The CNE was calculated according to the noise intensity of the workplace, and the occupational health check was carried out to construct the structural equation model of noise to IMT. RESULTS: The detection rate of carotid atherosclerosis(CAS) in these 1 437 subjects was 38.3%. The CAS detection rates of steel workers increased with the increasing CNE(P<0.01). The structural equation model had good fitting effect. Path analysis showed CNE can indirectly affect IMT through blood pressure, triglycerides, fasting blood glucose, homocysteine, high-density lipoprotein & apolipoprotein A, low-density lipoprotein & apolipoprotein B. The total effects were-0.375, 0.337, 0.248, 0.117, 0.056, 0.056 and 0.018 respectively. CONCLUSION: CNE can indirectly increase the IMT of steel workers by acting on the proximal cause.

OBJECTIVE: To explore the effect of occupational high temperature exposure on type 2 diabetes( T2 DM) in male steel workers. METHODS: A cluster random sampling method was used to select 684 male steel workers,who exposed to occupational high temperature in a steel enterprise in Tangshan City,as the high temperature group,and 1 153 male steel workers without occupational high temperature exposure as the control group. The high temperature level of workers in these two groups was measured. The cumulative exposure( CE) of high temperature was calculated,and occupational health exam was performed. The multivariate logistic regression analysis and restricted cubic splines were used to analyze the relationship between high temperature CE and T2 DM. RESULTS: The prevalence of T2 DM in high-temperature group was higher than that in the control group( 13. 0% vs 7. 9%,P < 0. 05). The multivariate logistic regression analysis results showed that the risk of T2 DM in the high temperature group was higher than that in the control group after adjusting for age,body mass index,smoking,drinking,physical exercise and parents with diabetes( P < 0. 05). The 95% confidence interval was 1. 65( 1. 17-2. 33). Restricted cubic spline analysis showed that the high temperature CE was correlated with the prevalence of T2 DM in workers( P < 0. 01) and showed a linear correlation( nonlinearity test,P > 0. 05). CONCLUSION: Occupational high temperature exposure is associated with the occurrence of T2 DM in male steel workers. The male steel workers with high temperature CE show high prevalence of T2 DM risk.