الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Noise is a recognized physical hazard present in workplaces. Many people worldwide suffer from the auditory and non-auditory health effects of noise, either in occupational settings or non-occupational. There is scarce literature about noise in the confectionery (chocolate and sweets) processing plants. Various risk factors have been documented to be associated with an increased risk of developing hearing loss, such as age, noise exposure, exposure to heavy metals and organic solvents, and chronic diseases such as hypertension and diabetes.
This cross-sectional study was designed to study the relationship between noise induced audiometric changes and the background health status of workers. It was designed to study the association between noise induced hearing loss and some risk factors such as hypertension, DM, COPD, and cigarette smoking.
The study included 100 workers from a food processing plant working in the production, packing, and administrative departments. Forty-two workers in the production area were exposed to noise levels of 85 dB and above, 43 in the packaging department were exposed to more than 75 dB but less than 85 c, and 15 workers in the administrative department were exposed to noise levels ranging from 60 to 70 dB.
All workers were subjected to a pre-designed interviewer questionnaire which was modified in order to obtain information relevant to this study. The medical history of workers was inquired, including the history of having hypertension, diabetes, COPD, use of ototoxic medications, smoking, history of head trauma, and any history of ear problems. Blood pressure measurements were taken, and all workers were subjected to an audiometry test. Sixty-six workers were subjected to lung function tests because some of the workers had contraindications.
Data analysis revealed that having chronic diseases was not associated with hearing loss. However, being exposed to high noise levels was significantly associated with elevation of both systolic and diastolic blood pressure and deterioration in lung function. Noise induced hearing loss was significantly associated with increasing age and duration of noise exposure.
Workers exposed to noise levels below 85 dB had higher prevalence of hearing loss than those exposed to more than or equal to 85 dB. All workers in areas with high noise levels were observed to be using ear protection, this explains the difference.
Almost 50% of the study participants were smokers. The prevalence of hearing loss was significantly higher among workers who were both smokers and exposed to a high level of noise than among smokers not exposed to a high noise level. This indicates the combined effect of high levels of noise and smoking in causing hearing loss.
On multivariate logistic analysis, the duration of high level noise exposure above 85 dB of more than 20 years was a significant predictor of NIHL after adjusting for age. Noise exposure above 85 dB is significantly associated with increased diastolic blood pressure after adjusting for diabetes, duration of noise exposure, and age of more than 35 years.
The prevalence of NIHL is higher even among workers exposed to noise levels below 85 dB. Control of noise in workplaces is of paramount importance in reducing the problem of hearing loss. We should also focus on the non-auditory effects of noise as there is association between noise exposure and some chronic diseases.
6.2 Conclusion
1. The overall prevalence of NIHL among workers was high (44%) despite being exposed to noise levels below the Threshold Limt Value (TLV).
2. There is a significant association between NIHL and increased duration of noise exposure.
3. The combined effect of smoking and high level noise exposure was observed, smoking among workers exposed to noise level of more than 85 decibel was a significant risk factor in developing NIHL.
4. Hearing loss has no significant association with blood pressure, however noise exposure per se was significantly associated with elevation in blood pressure.
5. Increasing age of more than 50 years has an increased risk of NIHL.
6. High blood pressure and changes in pulmonary function tests increase the susceptibility of workers exposed to noise level below 85 dB to noise induced hearing effects.
7. Workers in production department were exposed to noise levels above 85 dB, those in packing department were exposed to levels from 75 dB to 85 dB and workers in administrative area were exposed to noise levels below 75 dB.
6.3 Recommendations
Based on the findings of this study, we recommend the following:
1. Recognition of personal habits such as smoking as a risk factor that increase susceptibility to noise induced hearing loss. Workers who are smokers and exposed to high-level noise should be monitored by periodic audiometry tests.
2. Pre-employment medical examination should include audiometry, BP measurements and PFT’s of all new workers.
3. Periodic medical examination including audiometry, BP and PFT’s should be done on all workers exposed to high level noise above 85 dB.
4. Continuous health education to workers about noise as an occupational hazard that can affect their health, productivity, and hearing acuity and the use of HPDs.
5. There should be a smoking cessation program together with other precautions such as HPD because almost 50% of workers were smokers, and it was seen that the combined effect of cigarette smoking and noise was associated with an increased risk of hearing loss.
6. Anti smoking programs and occupational health programs to preserve the health status of workers.
7. Coupling health promotion programs with measurements of blood pressure and pulmonary functions tests to the basic tool of screening for hearing is of utmost importance for protection of overall health status for noise exposed workers.