Objective To analyze the effect of hand transmitted vibration on fingertip thermotactile perception threshold (TPT) among grinding workers in a sports equipment manufacturing enterprise. Methods A total of 151 male grinding workers from a sports equipment manufacturing enterprise in Guangdong Province were enrolled in the vibration exposure group, and 51 male workers without hand-transmitted vibration exposure were enrolled in the control group, using the judgment sampling method. Basic health conditions of the workers were surveyed in both groups. The TPTs of the distal phalanges of the index and little fingers on both hands were tested using an HVLab thermal perception tester. Results The detection rates of finger numbness and tingling among workers in the vibration exposure group were higher than those in the control group (92.1% vs 7.8% and 59.6% vs 0.0%, respectively, both P<0.01). The detection rates of numbness or tingling of different fingers in the vibration exposure group descended in the following order: index finger, middle finger, ring finger, thumb and little finger. The hot threshold of the index finger and little finger increased (all P<0.01), while the cold threshold decreased (all P<0.01) in the vibration exposure group, compared with the control group. The results of generalized linear regression analysis showed that with the increase of the duration of hand-transmitted vibration, the hot threshold of the index finger and the little finger of both hands increased (all P<0.01), and the cold threshold decreased (all P<0.01). The hot thresholds of workers with numbness of both the index fingers and left little finger were higher than those of workers without numbness of the same finger (all P<0.05). The hot threshold of workers with tingling of the left index finger was higher than those without tingling (P<0.05). The cold thresholds of workers with tingling of the both index fingers and left little finger were lower than those without tingling of the same finger (all P<0.05). The hot threshold of the right little finger increased with age (P<0.01), while the cold thresholds of both little fingers decreased with age (all P<0.01). Conclusion Hand-transmitted vibration exposure increases fingertip hot threshold and decreases fingertip cold threshold of workers exposed to hand-transmitted vibration. Years of service in hand-transmitted vibration work, finger numbness or tingling, and age were influencing factors of TPT. Fingertip TPT examination can be used to assist in the early detection of vibration-induced nerve injury in workers exposed to hand-transmitted vibration.

OBJECTIVE: To analyze the effects of hand-transmitted vibration operation on nailfold capillaroscopy( NFC) in fine sanding workers. METHODS: A total of 57 fine sanding workers of one golf ball production enterprise in Guangdong Province were selected as vibration exposure group and 30 workers without exposure to hand-transmitted vibration as control group by a judgement sampling method. NFC examination was carried out in workers of these two groups. RESULTS: The capillary haemorrhage detection rates,percentage of abnormal capillary loops and total capillary width in the vibration exposure group were higher than that in the control group [43. 9% vs 13. 3%,( 56. 6 ± 20. 9) % vs( 41. 2 ± 14. 5) %,( 44. 7 ± 4. 9) vs( 42. 4 ± 4. 9) μm,P < 0. 05]. The capillary density,capillary length and branch diameter in the vibration exposure group were lower than that in the control group [( 7. 7 ± 1. 0) vs( 8. 8 ± 1. 0) per mm,( 185. 1 ± 33. 9) vs( 205. 6 ± 23. 2) μm,( 18. 3 ± 1. 9) vs( 19. 6 ± 2. 6) μm,P < 0. 05]. No significant difference was found in the diameter of apical part and branch of capillaries between the two groups( P > 0. 05). In the vibration exposure group,the percentage of abnormal capillary loops in the left hand was lower than that in the right hand [( 53. 1 ± 20. 6) % vs( 61. 5 ±24. 2) %,P < 0. 01],the capillary length in the left hand of vibration exposure group was longer than that in the right hand [( 187. 2 ± 33. 5) vs( 179. 4 ± 35. 4) μm,P < 0. 05]. No significant difference was found in the capillary density,total capillary width,apical part diameter,output branch diameter and input branch diameter between two hands in the vibration exposure group( P > 0. 05). CONCLUSION: The hand-transmitted vibration can lower the nailfold capillary density,shorten and widen capillary loops, increase percentage of abnormal capillary loops and induce capillary haemorrhage. NFC could be used to assist early detection of microvascular damage induced by hand-transmitted vibration.

OBJECTIVE: To understand the influence of shift work on common risk factors of cardiovascular disease in male workers in petrochemical enterprises.METHODS: A total of 981 male workers in a petrochemical enterprise were selected as study subjects by judgment sampling method.According to the current status of work shift,619 workers were in the shift group and 362 in the non-shift group.The differences in the related indicators of common risk factors of cardiovascular disease in these two groups were compared.RESULTS: The systolic blood pressure,diastolic blood pressure,uric acid,fasting blood glucose( FBG),and total cholesterol( TC) levels in workers of the shift group were higher than that in the non-shift group( P < 0.01).The diastolic blood pressure,serum FBG,TC,triglyceride levels,and obesity detection rate in the subgroup workers with a shift length ≥ 5.0 years were higher than that in the subgroup with shift length < 5.0 years( P < 0.05).The prevalence of hypertension,hyperglycemia,hyperlipidemia,and hyperuricemia in the study population were 9.3%,1.4%,19.9% and 33.4%,respectively.The prevalence of hyperuricemia increased with the increased working shift length( P < 0.01).The multivariate logistic regression analysis results showed that,the length of shift work was a risk factor for hyperuricemia( P < 0.01) after excluding the confounding factors such as age,body mass index,smoking and alcohol consumption.With the increase of the length of shift work,the risk of hyperuricemia increased.There was no correlation between shift working length and hypertension,hyperglycemia,and hyperlipidemia( P > 0.05).CONCLUSION: Shift work can increase the risk of hyperuricemia in male workers; shift work was not found to increase the risk of hypertension,hyperglycemia,and hyperlipidemia.