Improving the performance of double-expansion chamber muffler using dielectric beads; optimization using factorial design.

PURPOSE: Noise pollution is a common health hazard worldwide which is emitted along with chemical air pollutants, simultaneously from many sources. Some studies have been conducted to control these pollutants, simultaneously with promising results being achieved. Dielectric beads have been used in air pollution control technologies, successfully and probable effectiveness of them in noise reduction can be promising in dual use of them in the exhausts emitting noise and air pollution, simultaneously. METHODS: In order to investigate the effectiveness of dielectric beads in noise reduction, two types of them; namely glass and ceramic beads, were placed separately inside the connecting tube of a double-expansion chamber muffler. Then the transmission loss (TL) of muffler was examined using impedance tube. A factorial design was used to evaluate and optimize the effect of noise related parameters on TL of such a system. RESULTS: Results show that the presence of dielectric beads has significant effect on TL of muffler. The maximum TL was obtained as 74.76 dB for muffler with ceramic beads, under the optimal condition of 5250 Hz and 120 dB. Measurement of TL and sound absorption coefficient (SAC) of glass and ceramic beads showed that the noise reduction in muffler with ceramic and glass beads is probably due to SAC in ceramic beads and noise reflections in glass beads, respectively. CONCLUSION: These results promise the dual use of dielectric beads in the exhausts emitting noise and air pollution simultaneously.

Removal of sulfur dioxide from air using a packed-bed DBD plasma reactor (PBR) and in-plasma catalysis (IPC) hybrid system.

Sulfur dioxide, a noxious air pollutant, can cause health and environmental effects, and its emissions should be controlled. Nonthermal plasma is one of the most effective technologies in this area. This study evaluated the efficiency of a packed-bed plasma reactor (PBR) and in-plasma catalysis (IPC) in SO2 removal process which were finally optimized and modeled by the use of the central composite design (CCD) approach. In this study, SO2 was diluted in zero air, and the NiCeMgAl catalyst was selected as the catalyst part of the IPC. The effect of three main factors and their interaction were studied. ANOVA results revealed that the best models for SO2 removal efficiency and energy yielding were the reduced cubic models. According to the results, both PBR and IPC reactors were significantly energy efficient compared with the nonpacked plasma reactor and had high SO2 removal efficiency which was at least twice larger than that of the nonpacked one. Based on the results, the efficiency of IPC was better than in PBR, but its performance decreased over time. However, the PBR had relatively high SO2 removal efficiency and energy efficiency compared to the nonpacked reactor, and its performance remained constant over the studied time. In optimization, the maximum SO2 removal efficiency and energy efficiency were 80.69% and 1.04 gr/kWh, respectively (at 1250 ppm, 2.5 L/min, and 18 kV as the optimum condition) obtained by the IPC system which were 1.5 and 1.24 times greater than PBR, respectively. Finally, the model's predictions showed good agreement with the experiments.

Morphological, acoustical, mechanical and thermal properties of sustainable green Yucca (Y. gloriosa) fibers: an exploratory investigation.

BACKGROUND: The objective of this study was to evaluate the acoustical, morphological, mechanical and thermal properties of fibers extracted from the leaves of Yucca (Y. gloriosa) shrub. METHODS: Several tests were performed on either untreated or alkali-treated (5% NaOH) fibers. The chemical analysis of the fibers was performed to determine their lignin, cellulose, hemicellulose, wax and moisture content. Fourier transform infrared (FTIR) and thermogravimetric analysis were respectively employed to chemically and thermally analyze the fibers. The microscopic examination was also carried out using scanning electron microscope (SEM). INSTRON universal testing machine and an impedance tube system were employed for measuring the tensile properties of the fibers and the sound absorption coefficient values of the samples fabricated from the same fibers, respectively. RESULTS: The results from the experiments revealed that the fibers have low density (1.32 g/cm3) and higher cellulose content (66.36 wt.%,). The mechanical characterization of these fibers also confirmed they are similar to the other lignocellulose fibers used for the reinforcement of polymer matrix composites. The tensile strength test conducted on Yucca fibres showed that mechanical properties of alkali treated fibers are superior to the untreated fibers. The thermal analysis also demonstrated that the alkali treated fibres can thermally withstand temperatures of up to 364 °C which confirms the fact that the thermal stability of fibers was improved by alkali treatment. CONCLUSION: Fibers extracted from the leaves of Yucca demonstrated fair amounts of mechanical and thermal resistance and strength. The samples fabricated from Yucca fibers demonstrated fair levels of sound absorption coefficients particularly at higher frequency ranges which are typical to the other natural fibers. The possible use of Yucca fibers as either a reinforcing agent for composites or a sound absorbing medium is highly promising.

The effect of simultaneous exposure to cigarette smoke and noise on distortion product otoacoustic emissions in rats.

Cigarette smoking is a possible risk factor for hearing loss. However, the impact of simultaneous exposure to noise and smoke on hearing has remained controversial. This study investigated the combined effect of exposure to cigarette smoking and noise on hearing loss. Three groups of male Wistar rats (275 ± 25 g) were subjected to white noise (102 ± 0.5 dB), cigarette smoking (20 cigarettes), and both cigarette smoking and noise for 8 h and 10 days inside the exposure chamber. The control group was exposed to neither noise nor smoke. Distortion product otoacoustic emissions (DPOAE) were measured before any intervention, and it was repeated 1, 7, and 21 days after the last exposure. One-day postexposure to noise, cigarette smoking, and both cigarette smoking and noise, the mean of DPOAE amplitudes decreased significantly ( p < 0.05) between, respectively, 5.7-30.7, 1.5-7.5, and 5.2-32.6 dB within the frequency range of 4620-9960. Temporal DPOAE change in rats exposed to noise or both cigarette smoking and noise was not significantly different ( p > 0.05). DPOAE amplitudes returned to the baseline values in the group subjected to smoking 21 days postexposure. The most permanent change was observed in rats exposed to both cigarette smoking and noise. Accordingly, simultaneous subacute exposure to noise and cigarette smoking increases the effect of noise on permanent hearing loss. Therefore, smoking workers exposed to noise might be at a greater risk of developing hearing loss, and it is recommended that authorities in charge take note of this evidence.

Effects of coenzyme Q10 supplementation on oxidative stress and antioxidant enzyme activity in glazers with occupational cadmium exposure: A randomized, double-blind, placebo-controlled crossover clinical trial.

TRIAL REGISTRATION:: Iranian Registry of Clinical Trials Registration Number: IRCT2016061228407N1 ( www.who.int/ictrp/network/irct/en/ ).

The biochemical effects of occupational exposure to lead and cadmium on markers of oxidative stress and antioxidant enzymes activity in the blood of glazers in tile industry.

The aim of the present study was to evaluate the effects of occupational exposure to lead (Pb) and cadmium (Cd) on markers of oxidative stress in glazers in tile industries. Total antioxidant capacity (TAC), malondialdehyde (MDA), and the activity of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were determined in the blood of 80 subjects, including 40 glazers and 40 nonexposed subjects. Mean levels of blood Cd (8.90 ± 2.80 µg/L) and blood Pb (62.90 ± 38.10 µg/L) of glazers showed a significant increase compared with the control group. In the serum of glazers, the level of MDA was significantly higher and the level of TAC was significantly lower than the control group. We have noted a disturbance in the levels of antioxidants by a significant increase in the CAT activity and a significant decrease in the activities of SOD and GPx in the serum of glazers compared with the controls. Correlation analysis demonstrated that the serum MDA level and CAT activity were positively associated with the blood levels of Pb and Cd. Also, GPx and SOD were negatively correlated with blood Cd levels. The study clearly indicated that co-exposure to Cd and Pb can induce oxidative stress in glazers, resulting in increased lipid peroxidation and altered antioxidant enzymes.

Protective Effects of N-Acetyl-L-Cysteine on the Density of Spiral Ganglion Cells and Histological Changes Induced by Continuous Noise Exposure in Rats.

BACKGROUND: Noise exposure causes loss of cochlea hair cells, leading to permanent sensorineural hearing loss, and initiates pathological changes to the bipolar primary auditory neurons (ANs). This study focuses on the effects of N-acetyl-l-cysteine (NAC) in protecting the density of spiral ganglion cells and in histological changes induced by continuous noise exposure in rats. METHODS: Twenty-four male Wistar rats were randomly allocated into four experimental groups to receive NAC, saline, noise, or both noise and NAC. Noise exposure continued for ten days. Saline and NAC were injected daily during the noise exposure, and 2 days before and after the noise exposure. Evaluation of cochlear histopathology and the density of spiral ganglion cells was performed 21 days after exposure. RESULTS: In the animals exposed to noise, a reduction in the density of spiral ganglion cells was evident in both the basal and middle turns of the cochlea. This improved on receiving NAC treatment (P = 0.046). In the histopathology evaluation, some histological changes, such as disorganised architecture of the outer hair and supporting cells and a slightly thickened basilar membrane, were found in the basal turns in the noise group. CONCLUSION: NAC offered partial protection against noise exposure by improving the density of spiral ganglion cells and reducing morphological changes.

Retraction Note: Assessment of the influence of whole body vibration on Cochlear function.

[This retracts the article DOI: 10.1186/1745-6673-7-12.].

The risk of hearing loss associated with occupational exposure to organic solvents mixture with and without concurrent noise exposure: A systematic review and meta-analysis.

This study is a meta-analysis of the previous epidemiological studies which investigated the quantitative estimates of the association between independent or combined exposure to noise and mixed organic solvents and hearing loss until October 2014. Overall, 15 studies with information on 7530 individuals (6% female) were included. Having assessed - by puretone audiometry - the adjusted odds ratio estimates for the association between solvents mixture exposure and the risk of developing hearing loss stood at 2.05 (95% confidence interval (CI): 1.44-2.9). Similarly, for subjects who were concurrently exposed to noise and solvents mixture, an OR of 2.95 (95% CI: 2.1-4.17) was obtained. There was some evidence of heterogeneity within each of the 2 exposure groups (p heterogeneity < 0.001). This heterogeneity was not explained by differences in strength of effect between duration of exposure, the number of solvent and exposure index in subgroups of solvents mixture exposure. Based on the available data, our analysis has provided the evidence of increased risk of developing hearing loss for workers exposed to organic solvents even at quite low concentration. Moreover, if such exposure is accompanied by noise, it will exacerbate the extent of hearing loss. Int J Occup Med Environ Health 2017;30(4):521-535.

Exposure to chemical hazards in petrol pumps stations in Ahvaz City, Iran.

The objective of this study was to assess the level of exposure to BTEX (benzene, toluene, ethylbenzene, xylenes) in petrol pump stations in Ahvaz City. Two of the biggest fuelling stations were selected randomly among total 12 fuel stations of Ahvaz City, Iran, during September 2013. Thirty air samples were taken from different positions in the fuelling stations and 15 samples were taken from the personal breathing zone of operators and of customers in fuelling stations. Measuring the ambient concentration of benzene, toluene, ethylbenzene, and xylenes was done according to the method advised by National Institute for Occupational Safety and Health (NIOSH) 1501. This study showed that the concentration of benzene was very high (compared with the Iranian occupational exposure limit [OEL] standard) in ambient air of petrol stations in Ahvaz, which is considered as a high risk to the health of workers. Controlling the level of benzene in petrol stations is necessary. A new designed petrol nozzle was proposed for this purpose.

Evaluation of the influence of ergonomic intervention on the musculoskeletal disorders of Zahedan tailors.

Work-related musculoskeletal disorders are among the major health problems of tailors. This study was conducted with the aim of evaluating posture type, assessment of pain in body parts and the impact of education on the frequency of such injuries in tailors. This interventional study was performed in two groups of male tailors (45 cases, 45 controls) using Quick Exposure Checklist (QEC) software and the Nordic musculoskeletal questionnaire. The relationship between the qualitative variables was examined by χ2 test. Three months after the educational course, there was a significant decrease in the frequency of pain in most of the body parts (p < 0.05); mean of the QEC scores before the intervention was 79.04 ± 80.02 compared with 70.4 ± 8.3 after the intervention. It is suggested to hold cyclical educational courses along with other intervention programs for reducing the risks and dangers in the tailors.

Improving body posture while fueling with a newly designed pump nozzle.

BACKGROUND: Although petrol pumps are a very common and highly used simple technology, their design consideration for comfort and safety to prevent high-pressure load and musculoskeletal injuries to the body is a neglected area in many countries including Iran. OBJECTIVES: This study attempted to design a new pump nozzle, and to assess the differences in musculoskeletal load related to body posture when a price/volume display is mounted on the pump nozzle. METHODS: For postural analysis, photographs recording the posture of 100 randomly selected customers while fueling at petrol pumps and the rapid upper limb assessment (RULA) technique were used. RESULTS: The results of this study showed that RULA scores improved significantly after the newly designed pump nozzle was used. CONCLUSION: The newly designed pump nozzle is useful in reducing load related to body posture while fueling.

The Protective Effects of Gadolinum Chloride on Pneumotoxic Effects of Styrene in Rat.

OBJECTIVE: The aim of the present study was to evaluate the protective effects of gadoli- num on pneumotoxic effects of styrene in rats as an experimental model. MATERIALS AND METHODS: In this experimental study a total number of 40 adult male Sprague Dawley rats that weighed 200 ± 13 g were randomly divided into five groups: i. styrene (St, N=10), ii. styrene+gadolinium chloride (GdCl3, N=10), iii. control (N=10), iv. GdCl3 (N=5) and v. normal saline (Nor.Sal, as a solvent of GdCl3, N=5). Normal saline, as a sham control group, was otherwise treated identically. Rats from the experimental groups were exposed to St in an exposure chamber for 6 days/week, 4 hours/day for up to 3 weeks. At the end of the experi- ment, rats from all groups were killed by deep anesthesia. Their lungs were removed, then fixed in formalin and weighed. Tissue samples were processed routinely and sections stained by the hematoxylin and eosin (H&E) and periodic acid Schiff (PAS) methods. We measured the thicknesses of the respiratory epithelia and interalveolar septa. Obtained data were ana- lyzed by ANOVA, the Tukey test and the paired t test. RESULTS: Shedding of apical cytoplasm in the bronchiole was a prominent feature of the St group. PAS staining revealed histochemical changes in goblet cells in the epithelium of the St group. While there were no significant changes in lung weights and respiratory epithelial thicknesses between all studied groups, statistical analysis showed a significant alteration in the thickness of interalveolar septa in the St and St+GdCl3 group compared to the control groups (P<0.001). CONCLUSION: Styrene induced structural and histochemical changes in bronchiole, interalveolar septa and alveolar organization in the rats' lungs. Gadolinium appeared to partially reduce the toxic effects of styrene on the lungs.

Evaluation of ergonomic factors and postures that cause muscle pains in dentistry students' bodies.

BACKGROUND: Work-related musculoskeletal disorders commonly experienced by dental professionals are one of the main occupational health problem affecting their health and well-being.This study was conducted to evaluate ergonomic factors and profession-related postures and also investigate relationship between demographic factors and work condition with pain in dental students. MATERIAL AND METHODS: 60 freshman and sophomore dentistry students were randomly chosen as the subjects of control group, and 60 of 5th and 6th-year students were selected as the members of exposure group. Data related to the subjects such as sex, doing exercise, severity of musculoskeletal pain were obtained through questionnaire. Students' postures were directly observed while treating patients and they were scored by REBA method. Data were analyzed by SPSS software using Man-Whitney, Kruskal-Wallis, Spearman and Kendall correlation tests. RESULTS: 80.8% of the subjects were not aware of the correct ergonomic postures for dental procedures. Severity of musculoskeletal pain in the exposure group (15.9± 4.2) was significantly higher than the control group (10.5 ±3.2), (p <0.001). Risk of the most subjects (84%) was at the medium level. Students who were more involved in clinical activities experienced more muscular pains. CONCLUSIONS: The musculoskeletal disorders are probable prolonged in working hours in static positions, incorrect work postures, implying more force and even tools and instruments. Therefore, students who are aware of ergonomic principals of their own profession would be able to maintain their health through activities and lifelong. Key words:Posture, dentistry, students, musculoskeletal pain.

Evaluation of the effect of shift work on serum cholesterol and triglyceride levels.

BACKGROUND: Working outside daylight hours (7 am to 7 pm) is called shift work. Shift work is a common practice in many industries and factories such as steel industries, petroleum industries, power plants, and in some services such as medicine and nursing and police forces, in which professionals provide services during day and night. OBJECTIVES: Considering the contradictory reports of different studies, we decided to evaluate the effect of shift work on cholesterol and triglyceride (TG) levels through a historical cohort on steel industry workers. PATIENTS AND METHODS: This retrospective cohort study was performed on all the staff of Isfahan's Mobarakeh Steel Company between years 2002 and 2011. There were 5773 participants in this study. Data were collected from the medical records of the staff using the census method. For analysis of data, generalized estimating equation (GEE) regression was used. RESULTS: The results showed a significant difference in cholesterol levels between shift workers and day workers on the first observation (P < 0.001), yet no such difference was observed for TG (P = 0.853). Moreover, the results showed that the variables of age, work experience and BMI were not similar between shift workers and day workers. Therefore, to remove the effect of such variables, we used GEE regression. Despite the borderline difference of cholesterol between regular shift workers and day workers, this correlation was not statistically significant (P = 0.051). The results for TG also showed no correlation with shift work. CONCLUSIONS: According to the findings of this study, there is no relationship between shift work and changes in serum TG and cholesterol. The lack of relationship can be due to shift plans for shift workers, nutrition, or the "Healthy Heart project" at Isfahan Mobarakeh Steel Company.

Application of In-Syringe Dispersive Liquid-Liquid Microextraction Coupled to GC/FID for Determination of Trace Contamination of Phthalate Esters in Water Samples.

In this work, a simple and easy to handle one-step in-syringe setup for the dispersive liquid-liquid microextraction method has been developed for preconcentration of trace quantities of four kinds of phthalate esters (PEs) in water samples as a prior step to its determination by gas chromatography/flame ionization detector. The environmental pollution at this method has been limited due to using a glass syringe as extraction unit and also a very small amount of n-hexane as a safe solvent. Some important parameters such as the type of extraction and disperser solvents, extraction and disperser solvents volume, sample volume and ionic strength were investigated and optimized. Validation experiments showed that the optimized method had precision (1.7-6.9%) and high recovery (94.32-104.7%), and the limits of detection were from 0.406 to 1.33 µg L(-1). At the end, the method was successfully applied for the determination of PEs in real water samples.

Dominant role of drivers' attitude in prevention of road traffic crashes: a study on knowledge, attitude, and practice of drivers in Iran.

OBJECTIVE: Evaluating the relation between Iranian drivers' knowledge, attitude, and practice (KAP) regarding traffic regulations, and their deterministic effect on road traffic crashes (RTCs). SETTING: Two cities of Tehran and Zahedan, Iran. METHODS: A cross-sectional study was designed. Using a simplified cluster sampling design, 2200 motor vehicle drivers including 1200 in Tehran and 1000 in Zahedan were selected. Sixty locations in Tehran and 50 in Zahedan were chosen. In each pre-identified location, 20 adult drivers were approached consecutively. A questionnaire developed by researchers was filled by each participant. The questionnaire had four sections including items assessing the demographics, knowledge, attitude and practice of drivers toward traffic regulations. Logistic regression analysis was used to evaluate the relationship between the RTCs and KAP variables. RESULTS: The study sample consisted of 619 (28.1%) occupational and 1580 (71.8%) private drivers. Among them, 86.4% were male. The median age was 33.6 ± 10.83. Drivers in Tehran and Zahedan had no significant differences between their mean scores of KAP items of the questionnaire. Higher knowledge, safer attitude, and safer practice were associated with a decreased number of RTC. After adjusting for possible confounders, increase of one standard deviation in attitude and practice scores (but not knowledge) resulted in 26.4% and 18.5% decrease in RTC, respectively. Finally, considering knowledge, attitude and practice of drivers in one model to assess their mutual effect, it was shown that only attitude is significantly associated with a decrease of RTC (OR=0.76, P=0.007). CONCLUSION: Increase in attitude and practice accompanied with decreased number of RTCs in Iranian drivers. Specifically, drivers' attitude had the crucial effect. It is not knowledge and standard traffic education; rather it is how such education is registered as an attitude that translates what is being learned into actions. Without safer attitude, even safer self-reported practice will not result in lower RTCs.

Quantitative and qualitative evaluation of bio-aerosols in surgery rooms and emergency department of an educational hospital.

BACKGROUND: Bio-aerosols are a potential hazard in hospitals and are mostly produced by hospital staff, patients and visitors. Bio-aerosols are solid or liquid particles pending in the air and they consist of aerosols accompanying micro-organisms or organic compounds of micro-organisms such as endotoxin, metabolite, toxin and other parts of organism. Those are a potential hazard in hospitals and are mostly produced by hospital staff, patients and visitors. OBJECTIVES: This study aimed to determine the types and amount of bacterial contamination in operating rooms and emergency department of an educational hospital in Zahedan, South-East of Iran. MATERIALS AND METHODS: In this study, 72 samples were collected from three operating rooms and three rooms in the emergency department of an educational hospital during 2012. On the first day of every month, a sample was taken from each room during the morning shift; active sampling was done on plates consisting of blood agar and brain-heart infusion agar (BHI) for 10 minutes in the axis of a one-story Anderson impactor (flow rate 28.1 litter per minutes) and SIBATA air pump SIP 32-L and samples were then placed in a 35°C Incubator. Bacterial colonies were counted; warm coloring and differential tests were done and the data were analyzed using Mann-Whitney U and Kruskal-Wallis tests. RESULTS: Seventeen types of bacteria were detected including Staphylococcus, Micrococcus, Viridians, Pneumococcus, Escherichia coli, Streptococcus, Bacillus cereus, B. subtilis, Klebsiella, Pseudomonas, Diphtheroid, Citrobacter and Enterobacter. Quantitative bacterial results showed that the number of observed bacteria in the emergency department with an average of 103.88 ± 33.84 cfu/m³ was more than that of the surgery rooms with an average of 63.32 ± 32.94 cfu/m³. Furthermore, the highest average number of all counted colonies (106 ± 28.45 cfu/m³) was determined in autumn. In all samples, S. aureus and Micrococcus were the most detected bacteria. CONCLUSIONS: The World Health Organization (WHO) has suggested relatively relaxed limits of 100 cfu/m(3) for bacteria and 50 cfu/m(3) for fungi in the hospital air. Therefore, quantitative and qualitative outcomes of this study demonstrate that contamination level and bacterial variety in surgery rooms and emergency departments is high and effective measures must be taken to control the possible health risks.

The effects of water pipe smoking on hematological parameters in rats.

OBJECTIVES: This study aimed to investigate the effect of water-pipe (WP) smoking on hematological parameters of Wistar rats. METHODS: Thirty-five young male rats (200-250 g) were randomly assigned to five groups (n=7). The control group was exposed to room air and the experimental groups were exposed to WP smoking, using a special apparatus designed to have the ability to keep the rats for 40 minutes every day for 4, 8, 12 and 12 weeks; moreover, one of the two groups of 12 weeks of WP exposer had four following weeks of rest. Blood samples were collected to evaluate red blood cell count, hemoglobin, hematocrit, white blood cell and platelet counts. RESULTS: The results showed that RBC count, Hb and Hct parameters were significantly higher in WP smoking rats than the control group (P< 0.001). We found that WBC counts insignificantly increased (P < 0.39) but Plt counts insignificantly decreased (P < 0.13) in WP smoking rats compared with control group. CONCLUSION: The findings may help to raise awareness of tobacco smokers about the potential toxicities of WP; likewise, the results can be used by physicians and public health officials in tobacco prevention programs.

Cochlear damages caused by vibration exposure.

BACKGROUND: Many industrial devices have an excessive vibration which can affect human body systems. The effect of vibration on cochlear histology has been as a debatable problem in occupational health and medicine. OBJECTIVES: Due to limitation present in human studies, the research was conducted to survey the influence of vibration on cochlear histology in an animal model. MATERIALS AND METHODS: TWELVE ALBINO RABBITS WERE EXPERIMENTED AS: Vibration group (n = 6; exposed to 1.0 m.s(-2) r.m.s vertical whole-body vibration at 4 - 8 Hz for 8 hours per day during 5 consecutive days) versus Control group (n = 6; the same rabbits without vibration exposure). After finishing the exposure scenario, all rabbits were killed by CO2 inhalation; their cochleae were extracted and fixed in 10% formaldehyde for 48 hours, decalcified by 10% nitric acid for 24 hours. Specimens were dehydrated, embedded, sectioned 5 µm thick and stained with Hematoxylin and Eosin for light microscopy observations. RESULTS: Severely hydropic degenerated and vacuolated inner hair cells (IHCs) were observed in vibration group compared to the control group. Inter and intracellular edema was appeared in supporting cells (SC). Nuclei of outer hair cells (OHCs) seemed to be pyknotic. Slightly thickened basilar membrane (BM) was probably implied to inter cellular edematous. Tectorial Membrane (TM) was not affected pathologically. CONCLUSIONS: Whole-body vibration could cause cochlear damages in male rabbits, though vibration-induced auditory functional effects might be resulted as subsequent outcome of prolonged high level vibration exposures.