Objective: To study the hearing status and analyze the related influencing factors in noise-exposed workers in an automobile manufacture enterprise, and put forward suggestions for prevention of noise-induced hearing loss. Methods: Noise exposure level testing, audiometry testing and questionnaires were performed for noise exposed workers in the automobile manufacture enterprise. To analyze the relationship between different factors and noise-induced hearing loss by cumulative noise exposure(CNE) calculated 8-hour continuous A-weighted equivalent noise level and seniority. Results: The detection rate of hearing loss in noise-exposed workers was 22.8%. The noise exposure intensity of stamping workshop is higher than other workshop, and the hearing loss detection rate of stamping workshop workers is higher than other workshop workers. The detection rate of hearing loss has significant difference in L_{Aeq·8 h}, seniority, CNE, age, high temperature and wearing earplugs (P<0.05). The results of logistic regression analysis showed that CNE, age and high-temperature were risk factors for noise-induced hearing loss (P<0.05 and OR>1) and there was an increasing tendency of hearing loss with increase in length of service and CNE, while using of earplugs was a protective factor (P<0.05 and OR<1). With the increase of CNE, the incidence of hearing loss is the rising trend. Conclusion It is suggested to strengthen the noise control and individual protection and improve the high-temperature working environment, which plays an important role in reducing the occurrence of noise-induced hearing loss.

OBJECTIVE: To analyze the effect of occupational noise exposure on reproductive function in Chinese female workers.METHODS: The published literatures that showed the relationship between occupational noise exposure and female workers' reproductive function from Chinese National Knowledge Infrastructure,Wanfang Data,Chinese Biology Medicine Database and China Science and Technology Periodical Database from 1985 to 2016 were collected,screened and analyzed using bibliometric method.The Rev Man 5.2 software was used to calculate the pooled odds ratio(OR) and the 95%confidence interval(CI).RESULTS: A total of 25 original research papers were included.The occupational exposure to noise was significantly associated with abnormality of female menstrual cycle(OR = 2.26,95% CI: 1.70-3.01),dysmenorrheal(OR = 2.21,95% CI: 1.78-2.75),abnormal menstrual period(OR = 2.11,95% CI: 1.40-3.18),abnormal menstrual blood volume(OR = 1.73,95% CI: 1.34-2.23),pregnancy-induced hypertension(OR = 1.82,95% CI: 1.49-2.22),anemia in pregnancy(OR = 1.71,95% CI: 1.25-2.34),threatened abortion(OR = 1.98,95% CI: 1.23-3.20),spontaneous abortion(OR = 1.76,95% CI: 1.49-2.08),stillbirths(OR = 1.61,95% CI: 1.22-2.13),premature birth(OR = 1.57,95% CI: 1.36-1.81),neonatal low birth weight(OR = 1.66,95% CI: 1.39-1.98),and congenital malformations(OR = 1.58,95% CI: 1.10-2.27) compared with the controls(P<0.01).There was a doseresponse relationship between the above-mentioned indicators and the intensity of noise exposure.Occupational noise exposure was not associated with over-term birth(OR = 1.32,95% CI: 0.81-2.15,P>0.05) compared with the controls.CONCLUSION: Occupational noise exposure can affect the reproductive function and pregnancy outcomes of female workers.It is suggested that pregnant women should not be engaged in noise operations.

OBJECTIVE: To explore the effect of wearing earphone to listen to music on the high-frequency noise-induced hearing loss(NIHL) in noise-exposure workers. METHODS: A total of 651 male noise-exposure workers in an automobile manufacturer were selected as study subjects by using judgment sampling method. The level of noise exposure in the individuals and the pure tone hearing threshold were tested. According to the frequency of wearing earphone to listen to music after work, the subjects were divided into low-, medium-and high-frequency earphone-using groups, with 60, 436 and 155 workers in each group, respectively. The effects of wearing earphone to listen to music combined with occupational noise exposure on high-frequency NIHL were analyzed. RESULTS: The high-frequency NIHL detection rate of the study subjects was 31.3%(204/651). The detection rate of high-frequency NIHL in these three groups from low to high was low-, medium-and high-frequency earphone-using groups(P<0.01). The detection rate of high-frequency NIHL in the high-frequency earphone-using group was higher than that of the low-and medium-frequency earphone-using groups(43.2% vs 25.0%, 43.2% vs 28.0%, P<0.01). Multivariate logistic regression analysis showed that wearing earphones to listen to music was a risk factor for high-frequency NIHL in noise-exposure workers(P<0.01) after eliminating the influence of confounding factors such as age, length and level of noise-exposure, and wearing anti-noise ear plugs. The higher frequency of wearing earphone to listen to music, the higher risk of high-frequency NIHL. CONCLUSION: Wearing earphone to listen to music after work and occupational noise exposure had a synergistic effect on high-frequency NIHL in noise-exposure workers.