Noise pollution has huge impact on health
24 August 2007
Alarming new evidence from the World Health Organization (WHO) suggests that thousands of people around the world may be dying prematurely or succumbing to disease through the effects of chronic noise exposure.
The preliminary new figures released by the WHO state that long-term exposure to traffic noise may account for 3 percent of death from ischemic heart disease in Europe. Given that 7 million deaths from heart disease occur globally each year, this puts the death toll from noise exposure at a possible 210,000 deaths.
The figures also suggest that 2 per cent of Europeans suffer severely disturbed sleep from noise pollution and at least 15 percent suffer severe annoyance. The researchers calculate that chronic exposure to loud traffic noise causes 3 per cent of tinnitus cases, in which people constantly hear a noise in their ears. They also estimate the damage caused by noise pollution to children’s ability to learn and the damage caused by ‘leisure noise’ such as the use of MP3 players.
Deepak Prasher, professor of audiology at University College London, is a member of the coalition of scientists who helped to assemble and analyse the data. He told New Scientist magazine "the new data provide the link showing there are earlier deaths because of noise. Until now, noise has been the Cinderella form of pollution and people haven't been aware that it has an impact on their health."
The evidence comes from a WHO Working Group on the Noise Environmental Burden of Disease, which is a coalition of a number of expert scientists who have met a number of times to agree preliminary estimates of the impact of noise on the European population. It is hoped that the results of this study should provide sufficient evidence and justification for governments to take action on tackling noise reduction to improve health.
Recent research has found that noise can create a form of chronic stress that keeps our bodies in a state of constant alert. Noise exposure can increase the levels of stress hormones such as cortisol, adrenaline and noradrenaline in the body, even during sleep. This can cause long-term physiological changes that could be life-threatening, resulting in anything from heart failure and strokes to high blood pressure and immune problems. Professor Prasher told New Scientist "All this is happening imperceptibly, and this is the key…even when you think you're used to noise, these physiological changes are still happening."
The WHO research was triggered in part by the increase in complaints about noise pollution in recent years. The study compared households with high exposure to noise with quieter homes. It also studied people with problems such as coronary heart disease and tried to work out whether abnormally high exposure to noise increased their risk of dying. They combined this information with data from maps showing which parts of European cities are noisiest and could work out roughly how many people will die or suffer disease as a result of noise exposure.
Figures for Noise Night Guidelines for Europe are due to be presented by the WHO at an Inter-noise conference in Istanbul next week. According to these new guidelines, the noise threshold for cardiovascular problems is chronic night-time exposure of 50 decibels, the noise of light traffic. For sleep disturbance, the level is 42 decibels; for general annoyance it is 35 decibels.
