An overview of health effects on noise

Abstract

Although noise can damage the inner ear and cause other pathological changes, its most common negative effects are non-somatic, such as a perception of noisiness and disturbance of daily activities. According to the definition of health by WHO, this should be considered as a health hazard. These health effects of noise can be classified into the following three categories: (I) hearing loss, perception of noisiness and masking are produced along the auditory pathway and are thus direct and specific effects of noise; (II) interference with performance, rest and sleep, a feeling of discomfort and some physiological effects are produced as indirect and non-specific effects via reticular formation of the midbrain; (III) annoyance is not merely a feeling of unpleasantness but the feeling of being bothered or troubled, and includes the development of a particular attitude toward the noise source. Individual or group behavioral responses will be evoked when annoyance develops. Annoyance and behavioral response are integrated and composite effects. The health effects of noise are modified by many factors related to both the noise and the individual. Noise level, frequency spectrum, duration and impulsiveness modify the effects. Sex, age, health status and mental character also have an influence on the effects. Direct effects of noise are most dependent on the physical nature of the noise and least dependent on human factors. Indirect effects are more dependent, and integrated effects most dependent, on human factors.