Noise: what harmful effects on health?

Nearly 125 million European citizens suffer from noise pollution. According to the European Environment Agency (EEA), noise exposure is implicated in 43,000 hospitalizations and more than 10,000 premature deaths per year in Europe. On the occasion of the Sound week which takes place from January 20 to 26 in FranceWhy Doctor takes stock of the main harmful effects of noise on health.

Adverse effects on hearing

Who says noise says ears. Of course, the first risk associated with an excessive noise level concerns hearing. For an 8-hour working day, the latter is considered to be at risk from 85dB(A). If the noise level is higher, the exposure should be shorter. If the level is extremely high (above 130 dB(A)), any exposure, even very short, is dangerous. Because prolonged exposure to intense noise levels gradually destroys the hair cells of the inner ear. Progressive deafness then begins to set in.

Deafness has three stages : it starts with mild deafness, where the subject does not realize his hearing loss because the speech frequencies are little affected. Then, when he reaches the phase of moderate deafness, the high frequencies of the conversation are affected and he no longer clearly understands what is being said. Finally, when the person is affected by profound and irreversible deafness, he no longer hears or hears very little of what is being said.

Excessive noise can also lead to tinnitus (abnormal perception of noise in the absence of a sound source), hyperacusis (the ear becomes hypersensitive to certain sounds) or even acute sound trauma (sudden lesion due to a exposure to loud noises such as an explosion, fireworks or gunshot).

An increase in cardiovascular disorders

Numerous studies have shown that workers exposed to noise have a greater tendency to be prone to cardiovascular disorders. These would increase with the seniority of these employees in a noisy position. Indeed, noise increases heart rate and blood pressure (nearly 900,000 cases of hypertension are favored by excessive noise each year), cholesterol levels and the risk of heart attack.

sleep disorders

Exposure to noise during the night of course has negative consequences on the quality of sleep. Daytime exposure of 12 hours at 85 dB(A), for example, leads to a reduction in the number and duration of sleep cycles. Thus, noise disrupts the restorative function of sleep and can lead to chronic fatigue. This phenomenon is even more pronounced in people working at night who have to sleep during the day.

Negative effects on mental health

Several studies have also shown the negative effects of noise on mental health. According to a study published in the European journal of public health in May 2018, Danish researchers analyzed the results of health and morbidity surveys carried out in 2010 and 2013. They found that people who said they were very upset by the noises of their neighbors had 2.34 times more likely to be in poor mental health and were 2.78 times more likely to experience a high level of perceived stress than those who were indifferent to noise from their neighbours. Similar associations were observed with annoyance caused by traffic noise. In conclusion, “the results of this study indicate that there is a strong relationship between noise annoyance and poor mental health and high levels of perceived stress among people living in multi-storey housing in Denmark,” note the authors, stating that further research is “necessary to determine the direction of causation.”

In a survey carried out by the Noise Information and Documentation Center (CIDB) in 2010 on French people, 35% of respondents accused the noise of disturbing their sleep while for 26% it was a source of stress and for 22% fatigue and nervous tension. According to this survey, 10% would take medication because of the noise and the latter would have even made 7% of people fall into depression. Finally, 15% would consider moving because of noise pollution.