|LETTER TO EDITOR
|Year : 2013 | Volume
| Issue : 3 | Page : 155-156
Occupational noise induced hearing loss: Is planning appropriate type of shift work for the workers the most practical potential preventive measure?
Jayesh D Solanki, Hemant B Mehta, Chinmay J Shah, Pradyna A Gokhale
Department of Physiology, Government Medical College, Bhavnagar, Gujarat, India
|Date of Web Publication||2-Sep-2013|
Jayesh D Solanki
F1, Shivganga Appartments, Plot no 164, Bhayani ni waadi, Opp. Bawaliya Hanuman, Gadhechi Wadlaa Road, Bhavnagar 364001, Gujarat
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Solanki JD, Mehta HB, Shah CJ, Gokhale PA. Occupational noise induced hearing loss: Is planning appropriate type of shift work for the workers the most practical potential preventive measure?. Indian J Otol 2013;19:155-6
|How to cite this URL:|
Solanki JD, Mehta HB, Shah CJ, Gokhale PA. Occupational noise induced hearing loss: Is planning appropriate type of shift work for the workers the most practical potential preventive measure?. Indian J Otol [serial online] 2013 [cited 2019 Jun 18];19:155-6. Available from: http://www.indianjotol.org/text.asp?2013/19/3/155/117468
Having worked on my dissertation and published the work on Occupational Noise Induced Hearing Loss (ONIHL) in textile weavers in the latest issue of the journal,  I want to express my views on various possible preventive measures and their feasibility.
Occupation predisposes many of poor Indian workers of various industries to noise exposure at workplace. These innocent workers serve as continuous pattern being unaware of concept of Hearing Protective Devices (HPD), Periodic Audiometric Screening, and Interrupted Shift work regime. After working for few fruitful years for their family, they develop typical sensory-neural hearing loss,  which is not preventable at present. Most of the researchers try to find the prevalence of ONIHL and association of various factors, but they rarely test the prophylactic potential of various preventive rescue interventions and their effectiveness.
HPDs seem to be the most effective theoretical solution of this problem. HPDs are not acceptable means to minimize noise exposure and cannot substitute the benefit of avoidance of noise exposure, which is the most effective means. Further, there is no awareness regarding its use; a recent study challenges their effectiveness and comfort with real effective attenuation being lower than claimed nominal attenuation.  A recent Indian study further supports the need for preventive steps,  and one step is engineering control measures targeting production of less noisy equipments. However, this cannot be implemented in developing countries like India with scarcity of economical resources and commitment of higher authorities.
A recently published article reviewed prophylactic potential of various drug therapies concluding that at present there is no pharmaceutical agent available that satisfactorily alters pathology of the disease in curative direction.  Avoiding noise exposure is the only completely preventive option available but not practical.
Work planning measures are still left to be explored for their effectiveness and few animal and human studies have brought positive outcomes. For example, one can change the type of environment by periodic change in posting like spinning and weaving section of textile industries.
Being a mean of earning, workers cannot reduce the total number of working hours a week. However, intermittent noise exposure of moderate intensity noise, which is prevailing in many Indian manufacturing industries, can show protective effect on hearing owing to allowance of fairly adequate cochlear recovery between two consecutive noise exposures. 
In our study, we found that even in continuous day shift work, a brief interruption of 2 hours for lunch in female workers lead to better hearing threshold than those who worked uninterruptedly for similar number of hours a day in plastic weaving industry. Further, one day off per week resulted in poor hearing as compared with 2 days off per week. Chou et al.,  similarly found that noise-exposed employees working 12 hours per day for two consecutive days followed by 2 days off, the cycle then repeated, had significantly lower permanent hearing loss than those working 9 hours shifts for 5 days with weekends off.
In conclusion, this is just a hint to the health policy makers, industrial owners, noise exposed workers, and government officials about planning and optimum use of interrupted shift work type regimens and periodic rotation of jobs to prevent ONIHL. More studies with further innovative ideas can turn the hope into reality.
| References|| |
|1.||Solanki JD, Mehta HB, Gokhale PA, Shah CJ. A study of effect of shift work, sex and smoking on development of ONIHL in plastic weavers. Indian J Otol 2013;19:1-4. |
|2.||Solanki JD, Mehta HB, Gokhale PA, Shah CJ. Occupational noise induced hearing loss and hearing threshold profile at high frequencies. Indian J Otol 2012;18:125-8. |
|3.||Edwards J. The comfort and effectiveness of hearing protection devices. Ann Occup Hyg 2003;47:337. |
|4.||Singh LP, Bhardwaj A, Kumar DK. Prevalence of permanent hearing threshold shift among workers of Indian Iron and steel small and medium enterprises: A study. Noise Health 2012;14:119-28. |
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|6.||Campo P, Lataye RR. Intermittent noise and equal energy hypothesis. In: Dancer A, Henderson D, Salvi RJ, Hamernik RP, editors. Noise-Induced hearing loss. St. Louis: Mosby Year Book; 1992. p. 456-66. |
|7.||Chou YF, Lai JS, Kuo HW. Effects of shift work on noise induced hearing loss (NIHL). Noise Health 2009;11:185-8. |