unwanted noise seems to be a fact of modern life, but it can seriously
affect our health in several ways, from causing deafness to pushing up our
blood pressure. So what can we do to limit the damage?
The roadworker's pneumatic drill, blaring pop music, the constant drone
of traffic and the roar of an overhead jet are just some of the noises
guaranteed to put most people's nerves on edge.
Besides damaging our hearing and, in extreme cases, causing irreversible
deafness, noise pollution can raise blood pressure and cause insomnia. It
has also been linked with psychiatric disorders such as anxiety. In fact,
continual invasive noise has been known to drive people to suicide and even
Doctors first discovered the connection between hearing loss and
prolonged exposure to high noise levels some 250 years ago, when they noted
that many workers in the metal industry were deaf. In fact, it was an
occupational hazard among many workers; one type of noise-related hearing
loss was named 'boilermaker's deafness'.
Despite improved health and safety regulations, we are still suffering. One
recent study has revealed that more than 10 million Americans have had their
hearing damaged by noise and over 20 million are regularly exposed to noise
that could lead to hearing loss.
But these statistics also include the largely self-inflicted damage
caused by loud music on PA systems or personal stereos.
Excessively loud noise damages the sensitive hair cells in your cochlea,
or inner ear, which relay sound signals to the brain.
If you are only exposed occasionally to this kind of noise, you may
experience a temporary ringing in the ears and some hearing loss, but both
the damaged hair cells and your hearing will probably recover. Repeated
exposure, however, can cause permanent and irreversible damage. This in turn
can provoke chronic tinnitus, where the sufferer continually hears noises
inside their ears or head.
WHO IS AT RISK?
Some of us are more susceptible than others to the damaging effects of noise
on our hearing. It seems men are more easily affected, although this may
simply be because men are exposed more often to loud noise at work.
Blue-eyed people are more easily affected too. This may be because, being
generally fair-skinned, they have less of the skin pigment melanin which
seems to give the sensitive cochlea some protection from injury.
GETTING ON OUR NERVES
It is much more difficult to evaluate the psychological or behavioural harm
caused by noise annoyance, but the most common problem is thought to be
Intermittent noise is much more likely to upset sleep than prolonged
noise of the same degree of loudness. And emotionally-charged sounds like
the cry of a child or arguing neighbours are more likely to wake us than
Noise can also upset our sleep in more subtle ways. It can shift us from
heavy sleep into lighter sleep, reduce rapid eye movement (REM) sleep - the
segment in which dreaming occurs - and lead to more tossing and turning.
In turn, poor sleep can have a detrimental effect on our mood,
concentration, the performance of the heart and circulation.
Noise can often aggravate some disorders such as anxiety. Sensitivity to
loud noise has a definite link with most psychiatric illnesses, as-they tend
to lower the sufferer's usual tolerance level of noise.
There is also evidence that continual noise annoyance can play a
significant role in other disorders - for instance, it can increase the risk
of stroke, cardiovascular disease, high blood pressure (hypertension) and
However, some sounds exert a beneficial effect on our health. Listening to
enjoyable sounds at safe decibel levels encourages our bodies to release
endorphins - natural morphine-like brain chemicals that help us to relax and
boost our mood.
Music at the same tempo as our heart rate - around 70-80 beats a minute -
is perceived as soothing. The faster it gets, the more it raises tension,
while very slow music seems to create suspense.
HOW TO SWITCH OFF
It's a good idea to wear good quality ear protectors or plugs if you know
you are going to be subjected to loud noise for a prolonged period.
If you go out with a personal stereo, don't turn it above the level you
would use in a quiet room.
Keep the volume of domestic sound systems at a sensible level. As a rule
of thumb, you should never have to raise your voice more than slightly to
carry on a conversation when there is music in the background.