The effect of occupational noise exposure on systolic blood pressure, diastolic blood pressure and salivary cortisol level among automotive assembly workers

Introduction. Both auditory and non-auditory health can be affected by exposure to occupational noise. The aim of this study was to evaluate the association of high occupational noise (at three levels) with systolic blood pressure (SBP), diastolic blood pressure (DBP) and salivary cortisol concentration in an automotive factory. Methods. This study was carried out on 78 male workers from a factory who worked in the warehouse unit (control group: 60-70 dB(A)) and assembly units (two test groups: 75-85 and 85-95 dB(A)). Data were collected through questionnaires and measurement of SBP, DBP, saliva cortisol concentration and body mass index (BMI), prior to and post occupational noise exposure. The measurements were performed twice/day and repeated after 10 days. Results. For each occupational noise level group, there was no significant association between cortisol level with age and BMI. The SBP and DBP in all groups increased significantly. Also, the average cortisol levels were similar in different groups before noise exposure, but were statistically different after occupational noise exposure. Conclusions. High occupational noise exposure increases the cortisol level and blood pressure, which are the major risk factors of cardiovascular disease.