The World Health Organization(WHO) has documented seven categories of adverse health and social effects of noise pollution, whether occupational, social or environmental: hearing impairment, interference with spoken communication, cardiovascular disturbances, mental health problems, impaired cognition, negative social behaviors and sleep disturbances.
The latter is considered the most deleterious non-auditory effect because of its impact on quality of life and daytime performance.
Environmental noise, especially that caused by transportation means is a growing
problem in our modern cities. It is considered a major cause of exogenous sleep disturbances after somatic problems and day tensions.
Sleep is an important modulator of hormonal release,
glucose regulation and cardiovascular function. In particular
slow-wave sleep,the most restorative sleep stage,is associated with decreased heart rate,blood pressure,sympathetic nervous activity and cerebral glucose utilization,compared with wakefulness. During this sleep stage, growth
hormone is released while stress hormone cortisol is inhibited.