By Roger Highfield, Science Editor
Last Updated: BST
Noise may be the root cause of around three deaths in every
hundred traditionally blamed on heart disease according to a study that
suggests many thousands of people in
More people than ever are now complaining about unwanted noise pollution - from rowdy neighbours and loud traffic to late-night pubs and clubs.
Now ground-breaking research from the World Health Organisation has provided estimates of the impact of noise on the European population, reports New Scientist today, revealing a striking contribution of noise to premature deaths from accidents and disease.
Though preliminary, the WHO's findings suggest that long-term exposure to traffic noise may account for three per cent of deaths from ischaemic heart disease in Europe - typically strokes and heart attacks.
Given that 7 million people around
"The new data provide the link showing there are earlier deaths because of noise," the magazine was told by Deepak Prasher, professor of audiology at University College London, and a member of the coalition of European scientists who helped assemble and analyse the data, which will be published before the end of this year.
"Until now, noise has been the Cinderella form of pollution and people haven't been aware that it has an impact on their health," he says.
Noise is linked with heart attack and stroke because it
creates chronic stress that keeps our bodies in a state of constant alert.
Research published last year by
However, if these stress hormones are in constant circulation, they can cause long-term physiological changes that could be life-threatening. The end result can be anything from heart failure and strokes to high blood pressure and immune problems. "All this is happening imperceptibly, and this is the key," said Prof Prasher.
Dr Rokho Kim, of the WHO/EURO Centre
for Environment and Health,
However, he said that, compared with sleeping eight or more hours each night, sleeping 6 to 7 hours was associated with a 1.8 times higher risk for involvement in a sleep-related crash versus a non-sleep-related crash, and sleeping fewer than five hours per night invoked a 4.5 times higher risk.
Standardised tests and questionnaires in the classroom reveal a small - fraction of a percent - but significant impact of noise on eduction.
"Chronic aircraft noise exposure impaired reading comprehension and recognition memory," Dr Kim told The Daily Telegraph. "Among various effects on education, "reading test" and "memory-recall test" are more significantly affected by aircraft noise."
Prof Trevor Cox,
"Her research showed a significant relationship between SAT scores and noise levels, and that primary schools with external noise levels below the current guidelines failed to meet the Government's maths and literacy targets.
"Professor Stephen Stansfeld in the RANCH project (Road Traffic and Aircraft Noise. exposure and Children's Cognition and Health) showed that a 5dB increase in aircraft noise resulted in a 2 month delay in reading attainment."
The new WHO figures also suggest that two per cent of Europeans suffer severely disturbed sleep because of noise pollution, and at least 15 per cent suffer severe annoyance. The researchers calculate that chronic exposure to loud traffic noise causes three per cent of all cases of tinnitus, in which sufferers hear constant noise.
While the WHO has yet to finalise what levels of chronic exposure cause problems, though the threshold for cardiovascular problems, for example, is chronic night-time exposure of 50 decibels (dB) or above and a daytime exposure above 60dB.
Levels linked with annoyance are above 45dB and a disturbed sleep is above 40dB. The threshold judged to have a harmful impact on children's learning is 55 dB during night or day. However, the fraction of people affected "increases with increasing levels of exposure but the number in the population affected decreases," said Prof Prasher, so the overall impact on society declines.
The findings have emerged over the past four years as members of the WHO's Working Group on the Noise Environmental Burden of Disease project have sifted data from studies in countries including Germany, Switzerland and the Netherlands, to agree preliminary estimates of the impact of noise on the entire European population and separate its effects from those of traffic pollution and other confounding factors.
The WHO's investigations have been triggered in part by a rapid increase in complaints about noise pollution. Figures collected by the UK Office for National Statistics suggest that noise complaints to local government offices have increased fivefold over the past 20 years.
The Noise Abatement Society claims that local authorities, which are responsible for enforcing the regulations, are not getting the funds to do the job properly and The Daily Telegraph has launched its "Quiet, Please" campaign in response to the rise in complaints.
By the end of this year, cities with populations exceeding 250,000 will be required by European law to have produced digitised noise maps showing hotspots where traffic noise and volume are greatest.
Prof Prasher and other members of the WHO working group hope that revealing the scale of the health impact will help jolt more dismissive governments around the world into taking action to regulate noise.