Research Article Work-related musculoskeletal disorders: A case study among male molasses workers in Nadia district of West Bengal, India Gourab Biswas1, Arkajit Bhattacharya2, Rina Bhattacharya3 1 Department of Health, National Urban Health Mission, Santipur Municipality West Bengal, Santipur, West Bengal, India, 2Department of Community Medicie, Mata Gujri Memorial Medical College, Kishanganj, Bihar, India, 3Department of Environmental Science, University of Kalyani, Kalyani, West Bengal, India Correspondence to: Rina Bhattacharya, E-mail: rinaenv@yahoo.com Received: July 11, 2017; Accepted: October 08, 2017 ABSTRACT Background: Molasses making is one of the most agro-based sectors in India where about 4.50 core rural people are involved in the sugarcane cultivation and 5 lakh are directly engaged in the small-scale industries. The workers are prone to different health problems, but the effect has rarely been evaluated. Objectives: The aim of this study is to identify the musculoskeletal disorders of the molasses making workers and its association with age, experience, education, and addiction to smoking and alcohol. Materials and Methods: Working postures are analyzed by Ovako Working Posture Analysis System method. A modified Nordic questionnaire is used to survey the workers’ work-related musculoskeletal disorders (WMSDs), job details, and socioeconomic status. Statistical tests, namely, mean, standard deviation, odds ratio (OR), and 95% confidence interval (95% CI) are computed to analyze the data. Results: Due to poor working postures, a large number of workers are suffering from lower back and shoulder pain. Strong associations are observed between upper back pain with the age group of 31-45 years (OR 2.03, 95% CI [0.84, 4.91]) and illiterate (OR 2.06, 95% CI [0.90, 4.71]) workers. High ORs for musculoskeletal disorders are found among experienced and non-addicted workers. Conclusions: Definite pattern of risk factors can be obtained by including workplace stress and strain in the study. Awareness and educational campaign about the wrong working postures and WMSDs will help to reduce the risk factors. KEY WORDS: Work-related Musculoskeletal Disorders; Molasses Workers; Ovako Working Posture Analysis System, Odd Ratio INTRODUCTION India is placed at the 2nd position in the for sugar production. It is one of the most agro-based sectors which generate employment and income to the rural areas of the country. About 28 million tonnes of sugar are produced per year by 530 registered sugar factories, and hence, India emerges as a 2nd largest agricultural-based industry.[1] More than Access this article online Website: http://www.ijmsph.com DOI: 10.5455/ijmsph.2017.0719108102017 Quick Response code 4.50 core rural farmers are involved in the sugarcane cultivation and 5 lakh local village people are directly engaged in this industry.[2] In India, 65-70% sugarcane is used to manufacturing sugar, whereas 30-35% are used to producing molasses and Khandsari. Sugar industry produces nearly 65,000 tones molasses as a by-product which is used for alcohol and ethanol production. In addition to these organized sugar factories, thousands of rural people are engaged in the molasses-making activities through unorganized small cottage-based factories. Most of these locally molasses making factories are in private hands and to combat with the cost of production, they use workforce from rural areas. Locally, molasses-making process has different steps, namely, carrying of sugarcanes, grinding, taking out impurities, boiling of juice, mixing and stirring, and carrying International Journal of Medical Science and Public Health Online 2017. © 2017 Rina Bhattacharya, et al.. This is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), allowing third parties to copy and redistribute the material in any medium or format and to remix, transform, and build upon the material for any purpose, even commercially, provided the original work is properly cited and states its license. 2017 | Vol 6 | Issue 12 International Journal of Medical Science and Public Health 1706 Biswas et al. Work-related musculoskeletal disorders among male molasses workers to the storerooms. The whole processes are done manually by the workers and so most of them are suffering from different types of occupational health problems mainly work-related musculoskeletal disorders (WMSDs).[3,4] WMSDs are one of the most important causes for occupational hazards which not only affects the workers’ efficiency and health conditions but also at the same time it decreases the production rates and waste millions of working hours.[5-8] Many researchers have reported about the strong association between awkward working postures and WMSDs[9-15] Several studies have also shown that some others factors such as age, education level, working experience, smoking, and alcohol consumption can also affect the musculoskeletal system of the workers.[16-23] Lack of preventive measures for risk factors, prolonged working hours, poor working environment, and socioeconomic status are responsible for the poor health conditions of the workers which in turn increases the psychological stresses and leads to workplace injuries.[24] In this study, an attempt is made to identify the occupational health hazards particularly WMSDs among rural molassesmaking workers. MATERIALS AND METHODS Subject Selection In West Bengal, India, all molasses-making small-scale factories are running by private hands. Only 167 male molasses workers having at least 1 year working experience are randomly selected from such 16 small-scale factories for the present study. The aims and objectives of the study are clearly explained (Layman terms) to all the participants, and written consents of the workers are also obtained. Analysis of Working Postures Different working cycles of the molasses-making process are observed and recorded by video recording process (Canon SX110IS, Japan). Most frequently maintained working postures are analyzed by Ovako Working Posture Analysis System (OWAS) method.[27] Statistical Analysis Software MATLAB 7.0.4.365(R14) Service Pack 2 and SPSS version 3.5 are used for data analysis including mean value, standard deviation, odds ratio (OR), and 95% confidence interval (95% CI). RESULTS Physical characteristics with job details of molasses workers are presented in Table 1. The age of the workers ranges from 15 to 75 years. Most of the workers have normal BMI, blood pressures, and heart rate. The working experience of these workers is ranges from 1 to 55 years with the average working duration of 11 h/day with almost an hour break. Most of these molasses workers have meet accidents during their working life and felt very tired after day long hard work. Most common molasses working posture codes for carrying of sugar canes (P1), grinding (P2), filtering the juice (P3), boiling (P4), mixing of ingredients (P5), and storing (P6), respectively, are shown in Table 2. It is found that all frequently maintained working postures are harmful for the musculoskeletal system according to the OWAS. Workers are suffering from WMSDs in different body parts after day long hard work. Percent distribution of affected Physical and Physiological Parameters Anthropometric scale and weighing machine are used to measure the height and weight of the workers, respectively. Body mass index (BMI) of the molasses workers is calculated using the standard equation.[25] Blood pressures (systolic blood pressure or SBP and diastolic blood pressure or DBP) of the workers at resting state are taken twice by Srishti stethoscope (India) and Heine sphygmomanometer (Germany). The heart rate of the workers at resting state is also measured from the carotid artery by beats per minute count method. Table 1: Physical parameters and job details of the molasses workers Parameters Age (year) 36.5±14.1 Weight (kg) 54.9±10.3 Height (m) 1.62±0.07 BMI 20.9±3.5 <18.5 43 (25.7) 18.5-24.9 106 (63.5) >24.9 18 (10.8) Working experience (year) 17.9±13.9 Working hours/day Questionnaire Preparation Feeling tired A slightly modified Nordic questionnaire is used in this study to survey the workers’ WMSDs and job details.[26] The survey sheet had objective type questions with multiple choice answers, and communication is made through local language. Blood pressure (mm/Hg) 1707 Results (n=167) 10.9±2.6 146 (87.4%) SBP 130.7±18.3 DBP 81.1±10.6 Heart rate (bpm) 80.7±11.4 BMI: Body mass index International Journal of Medical Science and Public Health 2017 | Vol 6 | Issue 12 Biswas et al. Work-related musculoskeletal disorders among male molasses workers Table 2: Frequently maintain working postures with OWAS action category of molasses making workers Picture Stick diagram and OWAS AC P1 Picture 4273=4 P2 P3 Stick diagram and OWAS AC P4 4142=4 P5 4152=4 3151=4 4141=4 P6 2173=3 OWAS: Ovako Working Posture Analysis System body parts of the workers is illustrated in Figure 1. It is seen that the most affected body parts of the molasses workers are lower back and shoulder. Illiteracy rate (34.7%) is found very high among these workers, and only 11.4% of workers have completed their secondary level of education. Almost all these molasses workers are non-vegetarian, and 72.5% are addicted to smoking, whereas 55.1% are found alcoholic. The association between WMSDs with various factors such as age, education, experience, and addictions is observed and presented in the Tables 3 and 4. It is seen that most affected body part of the molasses workers is lower back irrespective of age, educational, experience, and addiction factors. It is observed that workers of 15-30 years of age group are found less affected from WMSDs compared to age group of 31-45 and >45 years. Strong associations are observed between the age group of 31 and 45 with upper back pain (OR 2.03, 95% CI [0.84, 4.91]) and also between the age group >45 years with ankle pain (OR 2.38, 95% CI [0.64, 8.81]). It is interesting to note that workers above primary level of education (others) have almost no WMSD risks. Molasses workers with 6-15 years working experience comparatively show lower risk to WMSDs, whereas workers with >25 years of working experience have the highest risks of WMSDs. High risk for ankle (OR 2.61, 95% CI [0.70, 9.71]), elbow (OR 1.95, 95% CI [0.94, 4.03]), and wrists (OR 1.77, 95% CI [0.58, 5.39]) are also found among the most experienced workers (>25 years). Workers, who are not 2017 | Vol 6 | Issue 12 Figure 1: Frequency distribution of different body parts discomfortability addicted to smoking and alcohol, are reported to have a more WMSD risk. DISCUSSION Lower socioeconomic class people of the local areas are directly engaged in molasses-making activity and exposed various types of hazardous working conditions every day. Instead of about 11 h of strenuous work which is more than the recommended working hours (The Factories Act, 1948).[28] They do not get sufficient calories to fulfill their nutritional budget, and hence, 25.7% of workers are suffering from underweight or malnutrition problems. In this study, we have found that more than 72% of workers are smoker International Journal of Medical Science and Public Health 1708 Biswas et al. Work-related musculoskeletal disorders among male molasses workers Table 3: Association of WMSDs with age and education among molasses workers Body parts n (%) OR 95% CI n (%) Neck 22 (31.4) 0.63 0.35, 1.14 26 (44.8) 1.12 0.61, 2.05 Shoulder 40 (57.1) 0.93 0.53, 1.65 38 (65.5) 1.33 0.71, 2.49 Elbow 10 (11.4) 0.50 0.22, 1.15 17 (29.3) 1.62 0.82, 3.19 Wrists/ hands 02 (02.8) 0.41 0.09, 1.93 05 (08.6) 1.33 0.44, 4.02 Age group 15-30 (n=70) OR 95% CI Illiterate (n=58) Upper back 02 (02.8) 0.25 0.05, 1.15 11 (18.9) 2.06 0.90, 4.71 Lower back 46 (65.7) 0.64 0.35, 1.17 48 (82.7) 1.61 0.74, 3.46 Hips/thighs 27 (38.5) 0.82 0.46, 1.46 22 (37.9) 0.80 0.43, 1.48 Knees 15 (21.4) 0.65 0.33, 1.20 20 (34.4) 1.26 0.67, 2.39 Ankle/feet 02 (02.8) 0.78 0.15, 4.00 03 (05.1) 1.46 0.35, 6.05 Age group 31-45 (n=48) Primary (n=27) Neck 27 (56.2) 1.78 0.93, 3.40 16 (59.2) 2.01 0.88, 4.60 Shoulder 31 (64.5) 1.28 0.65, 2.50 18 (66.6) 1.40 0.59, 3.31 Elbow 08 (20.8) 1.02 0.46, 2.27 08 (29.6) 1.64 0.66, 4.08 Wrists/ hands 05 (10.4) 1.64 0.54, 5.00 02 (07.4) 1.13 0.23, 5.42 Upper back 09 (18.7) 2.03 0.84, 4.91 02 (07.4) 0.70 0.15, 3.24 Lower back 41 (85.4 1.96 0.82, 4.71 19 (70.3) 0.79 0.32, 1.95 Hips/thighs 27 (56.2) 1.78 0.92, 3.42 13 (48.1) 1.22 0.54, 2.76 Knees 15 (31.2) 1.09 0.54, 2.19 07 (25.9) 0.84 0.33, 2.12 0 - - 02 (07.4) 2.14 0.41, 11.23 Ankle/feet Age group >45 (n=49) Neck Others (n=82) 21 (42.8) 1.03 0.54, 1.97 28 (34.1) 0.72 0.41, 1.25 Shoulder 27 (55.1) 0.86 0.45, 1.64 42 (51.2) 0.74 0.43, 1.26 Elbow 16 (32.6) 1.89 0.93, 3.84 09 (10.9) 0.48 0.22, 1.06 Wrists/ hands 04 (08.1) 1.26 0.38, 4.14 04 (4.88) 0.73 0.22, 2.36 Upper back 06 (12.2) 1.23 0.45, 3.31 04 (4.88) 0.45 0.15, 1.39 Lower back 38 (77.5) 1.16 0.54, 2.47 58 (70.7) 0.81 0.45, 1.46 Hips/thighs 18 (36.7) 0.76 0.39, 1.47 37 (45.12) 1.08 0.64, 1.84 Knees 19 (38.7) 1.52 0.78, 2.96 22 (26.83) 0.88 0.49, 1.59 Ankle/feet 04 (08.1) 2.38 0.64, 8.81 01 (1.22) 0.33 0.04, 2.79 WMSDs: Work-related musculoskeletal disorders, CI: Confidence interval, OR: Odds ratio and 55% are alcoholic to get relief from excessive workload, heavy physical, and psychological stresses of day-long work. Azagba and Sharaf have reported that the job stress has significant positive impact on smoking and alcohol consumption among the workers.[29] Molasses-making workers maintain different types of awkward working postures during their prolonged working hours. Due to bent and twisted back position, squatting with keens bent leg postures and load handled more than 20 kg make most of the postures hazardous to the musculoskeletal system. All frequently maintained molasses-making postures have an extreme harmful effect on the musculoskeletal system of the workers, and corrective measures should be taken immediately. Several studies have reported that wrong working postures during prolonged work can cause WMSDs among the 1709 workers.[30-32] Lower back pain can be occurred due to repetitive forward bending and twisting of the back position which exerts compressive pressures on the lower vertebra and its surrounding back muscles.[33-36] The present study is also shown that 76% of workers are suffering from lower back pain due to prolong maintain of bent and twisted back postures. It is also observed that, due to prolonged maintain of poor working postures, a large number of workers are suffering from shoulder and hips or thighs pain, followed by neck, knees, elbow, upper back, wrist, and feet or ankle discomfortability. Many researchers have shown that the risk of WMSDs increases with age of the workers.[37,38] In this study, it is observed that workers among 15-30 years age group are found less affected from WMSDs compared to higher age groups of workers. It is interesting to observe that workers with higher education levels (secondary and tertiary) are International Journal of Medical Science and Public Health 2017 | Vol 6 | Issue 12 Biswas et al. Work-related musculoskeletal disorders among male molasses workers Table 4: Association of WMSDs with experience and addiction among the workers Body parts n (%) OR 95% CI n (%) 15 (39.4) 0.90 0.44, 1.85 49 (40.4) 1-5 years (n=38) Neck OR 95% CI Smokers (n=121) 0.94 0.58, 1.51 0.62, 1.60 Shoulder 27 (71.0) 1.72 0.80, 3.71 71 (58.6) 0.99 Elbow 04 (10.5) 0.46 0.15, 1.38 24 (19.8) 0.97 0.54, 1.7 Wrists/hands 01 (02.6) 0.38 0.04, 3.06 10 (08.2) 1.27 0.52, 3.11 Upper back 02 (05.2) 0.49 0.10, 2.21 10 (08.2) 0.79 0.35, 1.80 Lower back 30 (78.9) 1.26 0.53, 2.96 92 (76.0) 1.06 0.61, 1.83 Hips/thighs 22 (57.8) 1.81 0.88, 3.70 51 (42.1) 0.96 0.59, 1.54 Knees 11 (28.9) 0.98 0.45, 2.13 37 (30.5) 1.06 0.63, 1.76 Ankle/feet 02 (05.2) 1.49 0.28, 7.68 04 (03.3) 0.91 0.25, 3.32 6-15 years (n=54) Non-smokers (n=46) Neck 18 (33.3) 0.69 0.36, 1.31 21 (45.6) 1.16 0.60, 2.24 Shoulder 27 (50.0) 0.70 0.38, 1.30 27 (58.6) 1.00 0.51, 1.94 Elbow 10 (18.5) 0.88 0.40, 1.94 10 (21.7) 1.09 0.49, 2.40 Wrists/hands 02 (03.7) 0.54 0.11, 2.54 01 (02.1) 0.31 0.03, 2.50 Upper back 07 (12.9) 1.31 0.51, 3.36 07 (15.2) 1.58 0.61, 4.08 Lower back 37 (68.5) 0.73 0.37, 1.43 33 (71.7) 0.85 0.41, 1.77 Hips/thighs 20 (37.0) 0.77 0.41, 1.45 21 (45.6) 1.10 0.57, 2.13 Knees 12 (22.2) 0.68 0.33, 1.41 12 (26.0) 0.84 0.40, 1.77 0 - - 02 (04.3) 1.21 0.23, 6.25 Ankle/feet 16-25 years (n=30) Alcoholic (n=92) Neck 15 (50.0) 1.38 0.63, 3.01 36 (39.1) 0.89 0.52, 1.49 Shoulder 16 (53.3) 0.80 0.36, 1.75 57 (61.9) 1.14 0.68, 1.93 Elbow 05 (16.6) 0.78 0.27, 2.19 16 (17.3) 0.82 0.42, 1.58 Wrists/hands 03 (10.0) 1.57 0.41, 6.02 02 (02.1) 0.31 0.06, 1.45 Upper back 01 (03.3) 0.30 0.03, 2.37 08 (08.6) 0.84 0.34, 2.02 Lower back 23 (76.6) 1.10 0.44, 2.75 74 (80.4) 1.38 0.74, 2.57 Hips/thighs 11 (36.6) 0.76 0.34, 1.70 43 (46.7) 1.15 0.69, 1.93 Knees 08 (26.6) 0.87 0.36, 2.10 25 (27.1) 0.89 0.50, 1.58 0 - - 01 (01.1) 0.29 0.03, 2.48 22 (48.8) 1.32 0.68, 2.56 34 (45.3) Ankle/feet >25 years (n=45) Neck Non-alcoholic (n=75) 1.14 0.66, 1.98 Shoulder 28 (62.2) 1.15 0.58, 2.28 41 (54.6) 0.84 0.49, 1.47 Elbow 15 (33.3) 1.95 0.94, 4.03 18 (24.0) 1.23 0.64, 2.36 Wrists/hands 05 (11.1) 1.77 0.58, 5.39 09 (12.0) 1.93 0.76, 4.88 Upper back 07 (15.5) 1.62 0.62, 4.20 09 (12.0) 1.20 0.51, 2.83 Lower back 35 (77.7) 1.17 0.53, 2.57 51 (68.0) 0.71 0.39, 1.29 Hips/thighs 19 (42.2) 0.96 0.49, 1.87 29 (38.6) 0.83 0.47, 1.45 Knees 18 (40.0) 1.60 0.81, 3.17 24 (32.0) 1.13 0.62, 2.04 Ankle/feet 04 (08.8) 2.61 0.70, 9.71 05 (06.6) 1.91 0.56, 6.48 WMSDs: Work-related musculoskeletal disorders, CI: Confidence interval, OR: Odds ratio less affected from musculoskeletal problems as this result is also supported by the previous works[39,40] which may be due to some knowledge and awareness about the risk factors presented in the working places. Häkkänen et al.[17] have reported that new workers are more susceptible to upper limb musculoskeletal disorders, 2017 | Vol 6 | Issue 12 whereas Noroozi et al.[22] have shown that workers more than 10 years of working experience have a higher risk of neck and back pain. In our study, high risks of the shoulder, lower back, hips, and ankles pain are observed among the beginners, whereas the lower risk of WMSDs is also found among the workers between 6 and 15 years of working experience. Workers with >25 years working experience International Journal of Medical Science and Public Health 1710 Biswas et al. Work-related musculoskeletal disorders among male molasses workers have the highest risk for musculoskeletal symptoms. It may be due to the age of the workers of this group (above 40 years), and they are engaged particularly in boiling (P4) and mixing of ingredients (P5) work which requires prolonged maintain of awkward back and leg postures. Association between smoking and musculoskeletal disorders has been reported in earlier studies.[18,19] Association between smoking and wrists, lower back, and knees is observed in our study. It is interesting to observe that alcohol addicted molasses workers have reported less musculoskeletal pain in different body parts. However, the effects of alcohol consumption on health are complex, and it is multidimensional, whereas Nelson et al. have reported that moderate drinkers perform better than the non-drinkers.[41,42] Due to prolonged and heavy work with poor working conditions and awkward working postures, 87.4% of workers are reported heavy tiredness after the work. The present investigation has pointed the occupational hazard present in the molasses-making workers despite some limitations. Lack of a large number of subjects from the study area imposes limits of the data interpretation. Another limitation of the survey is that health-related data were obtained from face-to-face interview of the workers as there was no health register. 4. 5. 6. 7. 8. 9. 10. 11. 12. CONCLUSIONS The present study shows that, due to prolong maintain of bent and twisted back posture and squatting with keens bent leg posture, most of the molasses workers are suffering from WMSDs. The most affected body part of the workers is lower back irrespective of age, educational, experience, and addiction factors. Higher risks for WMSDs are found among the most experienced, illiterate, non-addicted, and 31-45 years of age group workers. Proper awareness programs and educational campaigns can reduce the workplace risk factors. A recommended workrest scheduled[43] with the correction of hazardous working postures should be considered to lower the risk of WMSDs. The molasses workers are prone to different health problems, but it has been rarely assessed. The result of the present work may help the policymakers to take control measures for improving the workers’ health, quality of life, efficiency, and working environment. REFERENCES 1. 2. 3. 14. 15. 16. 17. 18. 19. Verma A. The Indian Sugar Industry: Current Status and Way Forward. Indian Sugar Mills Association; Available from: http://www.indiansugar.com/uploads/IBA_19_Sept_2015__ Final_pdf. [Last accessed on 2017 Jun 25]. Pandey AP. Indian sugar industry - A strong industrial base for rural India. Available from: https://mpra.ub.uni-muenchen. de/6065/. [Last accessed on 2017 Jun 25]. Choobineh A, Tabatabaee SH, Behzadi M. Musculoskeletal problems among workers of an Iranian sugar-producing 1711 13. 20. 21. 22. factory. Int J Occup Saf Ergon. 2009;15(5):419-24. Rocha FL, Marziale MH, Hong O. Work and health conditions of sugar cane workers in Brazil. Rev Esc Enferm USP. 2010;44(4):974-9. Kemmlert K. Labor inspectorate investigation for the prevention of occupational musculo-skeletal injuries, Solna. Sweden: National Institute of Occupational Health; 1994. Maul I, Läubli T, Klipstein A, Krueger H. Course of low back pain among nurses: A longitudinal study across eight years. Occup Environ Med. 2003;60(7):497-503. Chaffin DB, Andersson GB. Occupational Biomechanics. 3rd ed. New York, USA: Wiley; 1993. Karwowski W, Marras WS. Occupational Ergonomics: Principles of Work Design. Boca Raton, FL, USA: CRC Press; 2003. Aarås A, Westgaard RH, Stranden E. Postural angles as an indicator of postural load and muscular injury in occupational work situations. Ergonomics. 1988;31(6):915-33. Armstrong TJ, Buckle P, Fine LJ, Harberg M, Jonson B, Kilbom A, et al. A conceptual model for work-related neck and upper-limb musculoskeletal disorders. Scand J Work Environ Health. 1993;19(2):73-84. Genaidy AM, Karwowski W. The effects of neutral posture deviations on perceived joint discomfort ratings in sitting and standing postures. Ergonomics. 1993;36(7):785-92. Bernard BP. Musculoskeletal disorders and workplace factors. A Critical Review of Epidemiologic Evidence for Work-Related Musculoskeletal Disorders of the Neck, Upper Extremity and Low Back (NIOSH Publication No. 97-141). Cincinnati, USA: National Institute of Occupational Safety and Health; 1997. Bhattacharya R, Biswas G. Assessment of working postures and associated health status of construction workers. Sci Cult. 2011;77:52-7. Bhattacharya R, Biswas G, Bhattacharya A. Risk factors of upper limb musculoskeletal disorders of computer users: A preliminary report. Int J Electron Comm Technol. 2013;4 suppl 1:156-4. Biswas G, Ali M, Bhattacharya R. Occupational health risk of construction workers: A sample based study. Int J Pharm Res Biosci. 2016;5(3):129-41. Ueno S, Hisanaga N, Jonai H, Shibata E, Kamijima M. Association between musculoskeletal pain in Japanese construction workers and job, age, alcohol consumption, and smoking. Ind Health. 1999;37(4):449-56. Häkkänen M, Viikari-Juntura E, Martikainen R. Job experience, work load, and risk of musculoskeletal disorders. Occup Environ Med. 2001;58(2):129-35. Inoue M, Harada N. Habitual smoking and musculoskeletal symptoms in Japanese blue-collar workers. J Occup Health. 2002;44:315-20. Otani T, Iwasaki M, Ohta A, Kuroiwa M, Yosiaki S, Suzuki S, et al. Low back pain and smoking in a community in Japan. J Occup Health. 2002;44:207-13. Okunribido O, Wynn T. Ageing and Work-related Musculoskeletal Disorders-A Review of the Recent Literature. UK: Health and Safety Executive; 2010. Heiden B, Weigl M, Angerer P, Müller A. Association of age and physical job demands with musculoskeletal disorders in nurses. Appl Ergon. 2013;44(4):652-8. Noroozi MV, Hajibabaei M, Saki A, Memari Z. Prevalence of musculoskeletal disorders among office workers. Jundishapur International Journal of Medical Science and Public Health 2017 | Vol 6 | Issue 12 Biswas et al. Work-related musculoskeletal disorders among male molasses workers J Health Sci. 2015;7(1):1-5. 23. Thetkathuek A, Meepradit P, Jaidee W. Factors affecting the musculoskeletal disorders of workers in the frozen food manufacturing factories in Thailand. Int J Occup Saf Ergon. 2016;22(1):49-56. 24. Kalia HI. Occupational health of women. Ind J Occup Health. 2000;43:109-16. 25. Keys A, Fidanza F, Karvonen MJ, Kimura N, Taylor HL. Indices of relative weight and obesity. J Chronic Dis. 1972;25(6):329-43. 26. Dickinson CE, Campion K, Foster AF, Newman SJ, O’Rourke AM, Thomas PG. Questionnaire development: An examination of the Nordic musculo-skeletal questionnaire. Appl Ergon. 1992;23:197-201. 27. Karhu O, Kansi P, Kuorinka I. Correcting working postures in industry: A practical method for analysis. Appl Ergon. 1977;8(4):199-201. 28. Park K. Park’s Textbook of Preventive and Social Medicine: Occupational Health. 15th ed. Jabalpur: M/s Banarsidas Bhanot Publication; 1997. 29. Azagba S, Sharaf MF. The effect of job stress on smoking and alcohol consumption. Health Econ Rev. 2011;1(15):1-14. 30. Biswas G, Bhattacharya A, Bhattacharya R. Occupational health status of construction worker: A review. Int J Med Sci Public Health. 2017;6(2):669-74. 31. Singh V, Goyal M, Singh A, Bhatty SM, Prakash JS. Upper limp musculoskeletal disorders associated with computer usage in health-care professional. Int J Med Sci Public Health. 2015;4(11):1615-9. 32. Atri M, Nagraj A. Identifying musculoskeletal disorders amongst dentists-the needs for the hour. Int J Med Sci Public Health. 2014;3(6):730-4. 33. Frymoyer JW, Pope MH, Costanza MC, Rosen JC, Goggin JE, Wilder DG. Epidemiologic studies of low-back pain. Spine (Phila Pa 1976). 1980;5(5):419-23. 34. Chaffin DB, Anderson G. Occupational Biomechanics. New York, USA: Wiley; 1984. 35. Leskinen TP. Evaluation of the Load on the Spine Based on a Dynamic Biomechanical Model, Electromyographic Activity 2017 | Vol 6 | Issue 12 36. 37. 38. 39. 40. 41. 42. 43. of Back Muscle and Changes in Stature. Tampere, Finland: Tampere University of Technology; 1993. Das B, Sengupta AK. Evaluation of low back pain risks in a beef skinning operation. Int J Occup Saf Ergon. 2000;6(3):347-61. Guo HR, Chang YC, Yeh WY, Chen CW, Guo YL. Prevalence of musculoskeletal disorder among workers in Taiwan: A nationwide study. J Occup Health. 2004;46(1):26-36. Subramaniam S, Murugesan S Investigation of work-related musculoskeletal disorders among male kitchen workers in South India. Int J Occup Saf Ergon. 2015;21(4):524-31. Ekpenyong CE, Inyang UC. Associations between worker characteristics, workplace factors,and work-related musculoskeletal disorders: A cross-sectional study of male construction workers in Nigeria. Int J Occup Safety Ergon. 2014;20(3):447-62. Farioli A, Mattioli S, Quaglieri A, Curti S, Violante FS, Coggon D. Musculoskeletal pain in Europe: The role of personal, occupational, and social risk factors. Scand J Work Environ Health. 2014;40(1):36-46. Nelson HD, Nevitt MC, Scott JC, Stone KL, Cummings SR. Smoking, alcohol, and neuromuscular and physical function of older women. Study of Osteoporotic Fractures Research Group. JAMA. 1994;272(23):1825-31. Room R, Babor T, Rehm J. Alcohol and public health. Lancet. 2005;365(9458):519-30. ACGIH. TLVs and BELs. Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure Indices. Cincinnati: ACGIH Signature Publications; 2004. p. 168-76. How to cite this article: Biswas G, Bhattacharya A, Bhattacharya R. Work-related musculoskeletal disorders: A case study among male molasses workers in Nadia district of West Bengal, India. Int J Med Sci Public Health 2017;6(12):1706-1712. Source of Support: Nil, Conflict of Interest: None declared. 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