Combined effects of ototoxic solvents and noise on hearing in automobile plant workers in Iran

Exposure of workers to mixtures of organic solvents and to occupational noise is frequent in a number of industries. Recent studies suggest that exposure to both can cause a more severe hearing loss than exposure to noise alone. Our cross-sectional study included 411 workers of a large automobile plant divided in three groups. The first group included assembly workers exposed to noise alone; the second included workers in a new paint shop, who were exposed to a mixture of organic solvents at a permissible level; and the third group included paint shop workers exposed to both noise and higher than permissible levels of organic solvents in an old paint shop. These groups were compared in terms of low-frequency hearing loss (model 1; average hearing threshold >25 dB at 0.5 kHz, 1 kHz, and 2 kHz) and high-frequency hearing loss (model 2; average hearing threshold >25 dB at 3 kHz, 4 kHz, 6 kHz, and 8 kHz). High-frequency hearing loss was more common in workers exposed to a combination of noise and mixed organic solvents even at permissible levels than in workers exposed to noise alone even after correction for confounding variables. This study shows that combined exposure to mixed organic solvents and occupational noise can exacerbate hearing loss in workers. Therefore, an appropriate hearing protection programme is recommended, that would include short-interval audiometric examinations and efficient hearing protectors

Interaction of Physical Exposures and Occupational Factors on Sickness Absence in Automotive Industry Workers

INTRODUCTION: Increased sickness absence in recent years has been a trouble making issue in industrial society. Identify the causes of sickness absence and its influencing factors, is an important step to control and reduce its associated complications and costs. The aim of this study was to evaluate main factors associated with the incidence of sickness absence. PROCEDURE: In 2012, a cross-sectional study on 758 employees of a car accessories producing company was applied and relevant information about the number of days and episodes of sickness absence, Disease resulting in absence from work, personal features, occupational factors and physical exposures were collected. To determine risk factors associated with sickness absence, Logistic regression analysis was used. RESULTS: The most common diseases leading to sickness absence in order of frequency were Respiratory diseases, musculoskeletal disorders, gastrointestinal diseases and injuries at work. Musculoskeletal disorders increased the danger of long term absence by 4/33 times. Blue collar and shift works were the most important occupational factors associated with the incidence of sickness absence. The main physical factors that affect incidence of sickness absence were frequent bending-twisting and heavy lifting. CONCLUSION: Identifying controllable factors of sickness absence and trying to prevent and modify them such as compliance of ergonomic principals to decrease physical can be effective in reducing sickness absence

Effect of simultaneous exposure to occupational noise and cigarette smoke on binaural hearing impairment

In recent years, it has been postulated that cigarette smoking can aggravate noise-induced hearing loss. In this study, we aimed to assess the effect of concurrent exposure to cigarette smoke and occupational noise on binaural hearing impairment (BHI). In an analytic study on the workers of a large wagon manufacturing company in 2007, 622 male workers (252 smokers and 370 non-smokers, matched for other variables) participated and their BHI was compared. BHI was significantly higher in smokers than in non-smokers (odds ratio= 5.6, P < 0.001, 95 CI =3.4-9.4). Logistic regression confirmed this significant difference as well, and showed a direct relationship between the amount of BHI and pack/years of smoking. Cigarette smoking accompanied by exposure to workplace noise may play a role in causing binaural hearing impairment, so giving up or decreasing the amount of smoking may prevent or at least delay binaural hearing impairment, and eventually reduce its compensation costs

Cigarette smoking and occupational noise-induced hearing loss

Background: Noise is the most common occupational hazard. Noise-induced hearing loss (NIHL) is a known occupational disease. The economic costs of NIHL have been estimated to be billions of dollars. Besides, cigarette smoking is a common habit worldwide. Methods: In a cross-sectional study, we surveyed the effect of smoking on NIHL in 504 workers in a large wagon manufacturing company exposed to noise >85 dBA. All required data were obtained using direct interview and questionnaires. To determine noise exposure level, we used industrial hygienist's reports of sound level measurements. A qualified audiologist assessed hearing status using standardized audiometric examination. Results: We concluded that the frequency of hearing loss in smokers was higher than non-smokers based on Model 1: odds ratio (OR) = 9.35, 95 confidence interval (CI) = 5.74-15.22 and P-value < 0.001; and based on Model 2: OR = 9.06, 95 CI = 5.93-13.84 and P-value < 0.001. Besides, these results were confirmed by logistic regression statistical method. Conclusions: It can be concluded that smoking may accelerate NIHL, but for confirming this opinion, further studies are warranted. © 2009 The Author. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved

A Brief Approach to the Ear Recognition Process

This paper offers an approach to biometric analysis using ears for recognition. The ear has all the assets that a biometric trait should possess. Because it is a study field in potential growth, this study offers an approach using SURF features as an input of a neural network with the purpose to detect and recognize a person by the patterns of its ear, also includes, the development of an application with .net to show experimental results of the theory applied. Ear characteristics, which are a unchanging biometric approach that does not vary with age, have been used for several years in the forensic science of recognition, thats why the research gets important value in the present. To perform this study, we worked with the help of Police School of Ávila, Province of Spain, we have built a database with approximately 300 ears

Assessment of neurobehavioral disorders in workers exposed to organic solvents in a publication house

Background: Organic solvents are known as a group of organic compounds, widely used in industry and to which many workers are exposed. Neurotoxicity is one of the most important complications of the chronic exposure to the solvents and may causes neurobehavioral disorders in workers. We have studied the frequency of neurobehavioral disorders in workers exposed to organic solvents in one of the publishing houses in Tehran. Methods: In this cross-sectional study, 510 workers of a publishing house, having been employed at least a year before the research, were selected to be studied. Among them, 345 workers had been exposed to organic solvents and the other (165 workers) had not. Data were collected using a questionnaire. This questionnaire included demographic and occupational information, and the Swedish Q16 questionnaire. Variables included age, duration of employment, working shift, and smoking. Then we compared both groups in terms of neurobehavioral disorders, using statistical methods. Results: The mean score of the Swedish Q16 questionnaire in the exposed group (4.8±4.4) was significantly higher than the non-exposed group (3.2±3.1) (p=0.001). According to the questionnaire score, the frequency of neurobehavioral disorders in the exposed group was 38 and in the non-exposed group was 22 (p=0.001). We estimated that the frequency of neurobehavioral disorders in the exposed group was significantly higher than the non-exposed group (p<0.05) using regression analysis and removal of the confounding factors. Conclusion: This study shows that the frequency of the neurobehavioral disorders in the exposed group is significantly higher than the non-exposed group

Relationship of occupational and non-occupational stress with smoking in automotive industry workers

Background: Tobacco use is the second cause of death and first cause of preventable mortality worldwide. Smoking in the workplace is particularly concerning. Smoking-free workplaces decrease the risk of exposure of non-smoking personnel to cigarette smoke. Recent studies have mostly focused on the effect of daily or non-occupational stressors (in comparison with occupational stress) on prevalence of smoking. Occupational stress is often evaluated in workplaces for smoking cessation or control programs, but the role of non-occupational stressors is often disregarded in this respect. Materials and Methods: This cross-sectional study was conducted in an automobile manufacturing company. The response of automotive industry workers to parts of the validated, reliable, Farsi version of Musculoskeletal Intervention Center (MUSIC)-Norrtalje questionnaire was evaluated. A total of 3,536 factory workers participated in this study. Data were analyzed using SPSS and P<0.05 was considered statistically significant. Results: The correlation of smoking with demographic factors, occupational stressors and life events was evaluated. The results of logistic regression analysis showed that even after adjusting for the confounding factors, cigarette smoking was significantly correlated with age, sex, level of education, job control and life events (P<0.05). Conclusion: The results showed that of occupational and non-occupational stressors, only job control was correlated with cigarette smoking. Non-occupational stressors had greater effect on cigarette smoking. Consideration of both non-occupational and occupational stressors can enhance the success of smoking control programs. On the other hand, a combination of smoking control and stress (occupational and non-occupational) control programs can be more effective than smoking cessation interventions alone. © 2014 NRITLD

Menstrual disturbances and hormonal changes in women workers exposed to a mixture of organic solvents in a pharmaceutical company

Background: Chemicals are among risk factors that can affect women's reproductive system. This study is aimed to investigate the association of occupational exposure to a mixture of organic solvents with menstruation disturbances and hormonal changes among female workers. Methods: Female workers of a pharmaceutical company were divided into three groups of non-exposed, lowexposed and highly-exposed to a mixture of organic solvents (formaldehyde, phenol, N-hexane, and chloroform) based on workplace measurements. Menstrual disturbances (in terms of short cycles, long cycles, irregular cycles, and bleeding or spotting between periods) and mean of hormone levels (including follicle stimulating hormone, luteinizing hormone, thyroid stimulating hormone, prolactin, estrogen and progesterone levels) were compared between these three groups. For investigating associations, logistic regression was performed. Results: Our study showed that mean length of cycles, duration of bleeding, and amount of flow and also prevalence of long cycles, irregular cycles, and bleeding or spotting between periods were higher in exposed groups (p≤0.05). Odds ratio for prevalence of menstrual disturbances in the low exposure group and high exposure group were 9.69 (p=0.001) and 3.40 (p=0.002) respectively compared to the reference group. Estrogen and progesterone levels were not affected (p> 0.05), but other hormones levels were significantly disturbed in the exposed groups compared with the non-exposed group (p=0.001). Conclusion: Occupational exposure to the mixture of organic solvents may be associated with the increase of menstrual disorders and hormonal changes in female workers. Based on our findings, periodic evaluation of reproductive system of female workers in pharmaceutical companies is recommended

Assessment of the relationship between physical working conditions and different levels of work ability

Early leaving of workplace by work forces is one of the fundamental problems worldwide. Maintenance and enhancement of employees work ability are important for raising productivity. This study investigated the relationship between work ability index and physical working conditions and was carried out in 2013 on 641 workers at a manufacturing plant in Tehran. Work ability was assessed by the questionnaire of work ability index and the participants were classified into four work ability groups of poor, moderate, good, and excellent. Physical working conditions were evaluated by the MUSIC-Norrtalje questionnaire and the participants were classified into two groups with proper and poor physical working conditions. The mean score of work ability questionnaire was 42.40; and 2.5 (16 persons), 9.2 (59 persons), 38.2 (245 persons), and 50.1 (321 persons) of the participants were in poor, moderate, good, and excellent work ability groups, respectively. The mean score of physical working conditions questionnaire was 20.06. The results of logistic regression analysis showed that even after adjusting the confounding variables, a significant correlation existed between work ability and physical working conditions (p < 0.05). According to the results of this study, there may be a correlation between physical working conditions such as awkward postures, repetitive movements, load lifting, exposure to whole body vibration and so on with work ability. Therefore it seems that enhancement of the quality of physical working conditions may increase work ability