A noisy world is killing us
From Health cover this sound raises levels of stress hormones such as cortisol, adrenalin and noradrenalin — hormones which, if in constant circulation, can cause long-term physiological changes that could be life-threatening.
The health effects report identified certain groups of people who were more sensitive to the effects of noise pollution, and thus faced greater health risks. These included infants and school children, shift workers, the elderly, the blind and those suffering hearing impairment, sleep disorders and physical and mental health conditions.
The susceptibility of children correlates with a report in Lancet (2005 Jun 4-10; 365 (9475):1942-9), which found that chronic exposure to environmental noise, in particular aircraft and road traffic noise, leads to impaired cognitive function and health in children. It assessed almost 3000 children aged 9-10 years from 89 schools out of of 77 approached in the Netherlands, 27 in Spain, and 30 in the UK located in local authority areas around three major airports.
‘‘ Our findings indicate that a chronic environmental stressor — aircraft noise — could impair cognitive development in children, specifically reading comprehension,’’ the researchers concluded. ‘‘ Schools exposed to high levels of aircraft noise are not healthy educational environments.’’
According to Queensland’s Environmental Protection Agency (EPA), one of the bodies responsible for controlling unwanted racket, more than 40 per cent of Australians are disturbed at home or lose sleep because of noise pollution.
Yet compared to the public health issue of smoking, which becomes subject to ever more robust legislation and social stigma each year, community awareness of noise hazards remains relatively low.
In Australia, responsibility for the issue is diluted across a range of national, state and local governments.
It’s hoped the new WHO estimates will provide governments with stronger justification for controlling nuisance noise and help local authorities determine where, when and how to take action.
Still, turning down the volume on daily life is such an overwhelming task, it’s hard to know where to start, says Cowan: ‘‘ As a society we’re becoming more aware of (the impact of) loud levels of background noise but, ‘ What are we going to do about it?’ becomes a whole other question.’’
European nations are introducing some radical solutions to cut the din. By the end of the year, all European cities with populations exceeding 250,000 will be required by law to have produced digitised noise maps showing hotspots where traffic noise and volume are greatest.
Coupled with data on health effects, this should allow them to better target anti-noise measures, such as re-routing traffic away from hospitals and schools and erecting noise barriers. In the longer term, it will map high concentrations of social noise — around music venues, for instance.
This will then feed into planning regulations which will, say, prevent high density residential buildings being constructed or refurbished in areas of high social noise concentration.
Given that heavy truck traffic arguably creates far higher levels of noise than passenger cars, Cowan says other measures might include separating re-routing heavy transport from inner-city traffic. ‘‘ However, this would require significant further investment in infrastructure.’’
Other solutions that should be considered target the source of the noise — that is, the vehicle itself.
‘‘ One of the main sources of noise is the road noise from tyre contact,’’ says Cowan. ‘‘ While we design tyres and tyre compounds to have maximum grip for vehicle safety, perhaps funding for research into quieter tyres would address one of the source problems.’’
Initiatives aimed at promoting a culture of quieter exhausts, or quieter engines, could also be investigated.
‘‘ Just as we are considering a carbon or gas emission issue in cars, why not consider a noise emission rating? And perhaps provide tax incentives for car manufacturers to make quieter cars, and then encourage purchase of such vehicles,’’ says Cowan.
‘‘ We should note that airline companies are already investing heavily in quieter engines. The new Boeing Dreamliner has clearly identified quieter engines as a primary selling point for airlines and passengers, as well as being a boon to society,’’ he says.
But these and other potential solutions require time, money — and immense political and social will. ‘‘ It’s a more complex problem than just saying, ‘ Turn it down’,’’ says Cowan. ‘‘ I wish it were that simple.’’