Objective: To investigated the effect of long-term low-concentration mixed benzene exposure on peripheral blood of male workers. Methods: A case-control study was conducted to select 452 male workers exposed to mixed benzene (benzene, toluene, xylene) for five consecutive years from January 2012 to December 2016 in an automobile manufacturer as case group, and 438 male administrative and logistic managers who underwent physical examination during the same period as control group. The peripheral blood of the two groups was tested and compared, and the occupational hazards in the workplace were detected. Results: There were low dose exposure to mixed benzene in the enterprise, but the test results met the occupational exposure limit requirements. During the five years from 2010 to 2016, between the two groups of workers, the mean values of WBC, NEUT, RBC and Hb were statistically different (P<0.05). There was no statistical difference (P>0.05) in the mean value of PLT. The abnormal rate of main peripheral blood indexes in the control group was higher than that in the exposed group. There were significant differences in NEUT, RBC and Hb (P< 0.05), but no significant differences in WBC and PLT (P>0.05). Conclusion It can not be concluded that long-term low-concentration mixed benzene exposure can cause the change of peripheral blood index.

Objective: To investigate the current prevalence and prevention of work-related musculoskeletal disorders (WMSDs) among physicians for internal medical examination, and to provide a theoretical basis for the prevention and treatment of WMSDs in physicians for internal medical examination. Methods: In February 2017, 326 physicians for internal medical examination were randomly selected from 5 general tertiary hospitals and 2 specialized tertiary hospitals in a city of China. A questionnaire was designed according to the Nordic Musculoskeletal Questionnaire and the occupational features of doctors in China to investigate the prevalence of musculoskeletal pain over the past year, the cognitive attitude to WMSDs, the knowledge of WMSDs prevention, and ways to get the knowledge of WMSDs prevention. Results: In the tertiary hospitals of this city, the symptoms of WMSDs were mainly seen in the wrist (75.78%) , neck (67.19%) , and lower back (58.59%) among male physicians, and in the wrist (73.74%) , lower back (70.95%) , and upper back (60.89%) among female physicians. Compared with the female physicians, the male physicians had a significantly increased detection rate of symptoms of WMSDs in the neck (P<0.05) and significantly reduced detection rates of symptoms of WMSDs in the upper and lower back (P<0.05). There were significant differences between the detection rates of symptoms of WMSDs in the neck, wrist, and lower back within the past 12 months, 7 days, and >1 month (P<0.01). The rates of knowledge of the severity and prevention of WMSDs were significantly different between the physicians with different working years and professional titles (P<0.01) . Conclusion Among the physicians for internal medical examination in the tertiary hospitals of this city, WMSDs are mostly seen in the wrist, neck, and waist, and the knowledge of WMSDs prevention varies with different working years and professional titles.

ObjectiveTo investigate the correlation between genetic polymorphism of heat shock proteins 70 (HSP70) and susceptibility to occupational noise-induced hearing loss (ONIHL). Methods A total of 229 ONIHL workers were selected as the case group and 229 healthy workers with similar age, years of noise exposure, and noise exposure levels were selected as the control group using the case-control study method. Occupational health examinations were conducted on both groups, and peripheral blood of individuals was collected for DNA extraction. The genotypes of three single nucleotide polymorphisms of the HSP70 were detected using the MassArray system. Results The allele frequency distribution of HSP70 rs2227956, rs1043618, and rs1061581 in the control group was in Hardy-Weinberg equilibrium (all P>0.05). The genotype and allele frequency distribution of rs2227956 was significantly different between the two groups (all P<0.05), while no significant difference was found for rs1043618 and rs1061581 (all P>0.05). After adjusting for age, years of noise exposure, individual noise exposure level, smoking, and drinking, individuals with AG and AG+GG genotypes of rs2227956 had a higher risk of ONIHL than those with AA genotype (all P<0.05). The risk of ONIHL was higher in individuals with G allele of rs2227956 than in those with A allele (P<0.05). No correlation was found between rs1043618 and rs1061581 polymorphisms and the risk of ONIHL (all P>0.05). Conclusion The rs2227956 polymorphism of the HSP70 gene is correlated with susceptibility to ONIHL in noise-exposed workers, and the G allele is a risk factor for ONIHL in this population.

Objective: To investigate the prevalence of work-related musculoskeletal disorders (WMSDs) in male welders in different work areas of shipbuilding industry based on their operational working position and body position characteristics and to analyze the operational positions and ergonomic loads. Methods: In February 2017, 412 male welders from the hull and block work areas of a large ship factory were selected by stratified sampling. The prevalence and effects of WMSDs within a year were investigated using the Nordic Musculoskeletal Disorders Questionnaire, and a rapid exposure checklist was used to obtain the ergonomic load index by comprehensive scoring; the exposure-response relationship between the ergonomic loads and WMSDs symptoms of subjects in the hull and block work areas was evaluated. Results: Among the male welders working in the hull work area of shipbuilding industry, WMSDs occurred more commonly in the neck, lower back/waist, and legs, accounting for 53.16% (126/237) , 51.90% (123/237) , and 41.77% (99/237) , respectively; among those working in the block work area, WMSDs occurred more commonly in the lower back/waist, wrist, and legs, accounting for 52.57% (92/175) , 49.14% (86/175) , and 45.14% (79/175) , respectively. There were significant differences in the distribution of cases of pain within the last 7 days and one month, pain lasting more than one month, or absence from work due to pain within a year in the four positions between the two work areas (P<0.05). In the hull work area, high and extremely high exposure levels were mainly seen in the neck, lower back/waist, and legs, accounting for 76.79%(182/237), 69.20%(164/237), and 59.49%(141/237), respectively; in the block work area, high and extremely high exposure levels were mainly seen in the lower back/waist, wrist, and legs, accounting for 77.71%(136/175), 50.29% (88/175), and 46.29% (81/175), respectively. The detection rates of WMSDs in these four positions significantly increased as the exposure levels rose (P<0.01). Conclusion The WMSDs of male welders working in the hull and block work areas of shipbuilding industry occurs more commonly in the lower back/waist and legs. The risk of WMSDs symptoms increases with the rise of ergonomic load.

Objective: To understand the prevalence of gynecologic diseases among married female workers. Methods: The data of married female workers who underwent occupational health examination in a physical examination center from January to December 2017 were collected. The relationship between the detection of common gynecological diseases, age and occupational types examined by gynecological routine, TCT, breast B-mode ultrasound, uterus and appendix B-mode ultrasound were analyzed. Results: Among the 1142 female workers, the total detection rate of reproductive tract infections was 67.25% (768/1142), the total detection rate of breast-related diseases was 75.22% (859/1142) ; the total detection rate of gynecological tumors and benign lesions was 14.71% (168/1142). The detection rate of breast hyperplasia was the highest 67.08% (766/1142), followed by vaginitis 51.66% (590/1142). Among the abnormalities detected in breast-related diseases, gynecological tumors and benign lesions, the highest detection rate was found in public institutions (85.66% and 27.13%), and the lowest was found in factory workers (70.24% and 7.89%). With the increase of age, the detection rate of breastrelated diseases (breast hyperplasia, breast cyst), gynecological tumors, benign lesions (uterine myoma), and Nessler's cyst abnormalities in married female workers increased (χ²_trend=7.647、21.653、107.411、53.802, P<0.05), while the detection rate of columnar epithelium of cervix decreased (χ²_trend=7.404, P<0.05). There was no significant difference in the total detection rate of reproductive tract infectious diseases (vaginitis, cervical polyps, cervical hypertrophy) among married famale workers of different ages (P<0.05) . Conclusion The common gynecological diseases of married female workers are affected by many factors such as age and occupation. Health examination and health education should be carried out regularly to reduce the incidence of gynecological diseases among female workers according to different ages and occupations.