Chronic Effects of Noise Exposure on Physiological and Psychological Parameters in Petrochemical Workers: A Cross-Sectional Investigation

Abstract

Objective: This study aimed to evaluate the chronic impact of occupational noise exposure on physiological and psychological outcomes, including blood pressure, cortisol levels, aggression, and auditory annoyance, among petrochemical workers. Methods: A cross-sectional study, in 2025, was conducted on 300 petrochemical workers. Participants were divided into two groups, including 130 workers exposed to noise levels lower than 85A-weighted decibels (dB(A)) and 170 workers exposed to noise levels higher than 85 dB. Then, data related to demographic parameters, noise levels (using Casella CEL 815 sound level meter), blood pressure, salivary cortisol level (using measured using the enzyme-linked immunosorbent assay), and psychological outcomes (using validated questionnaires for annoyance and aggression) were collected. Statistical analyses included independent t-test, Pearson correlation, and multivariate regression. Results: Workers exposed to noise higher than 85 dB compared to individuals exposed to lower than 85 dB had significantly higher systolic blood pressure (SBP) (133.67 +/- 10.33 mmHg vs. 119.99 +/- 9.41 mmHg, P < 0.001) and diastolic blood pressure (91.79 +/- 3.92 mmHg vs. 82.76 +/- 3.84 mmHg, P < 0.001), total aggression scores (122.45 +/- 11.92 vs. 76.06 +/- 9.85, P < 0.001), and cortisol level (22.09 +/- 3.96 & micro;g/dL vs. 14.23 +/- 3.09 & micro;g/dL, P < 0.001). Auditory annoyance (8.48 +/- 1.63 vs. 4.40 +/- 1.41, P < 0.001) mediated 53 of the noise effect on SBP and 48 of its effect on cortisol level. Conclusion: Chronic noise exposure can significantly affect cardiovascular and mental health of petrochemical workers, with annoyance as a key mediating factor. These findings underscore the importance of noise reduction strategies and regular health monitoring to decrease occupational health risks.