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Vehicle noise and the toll on people
by Jonathan Orlando
"Calling noise a nuisance is like calling smog an
inconvenience. Noise must be considered a hazard to the health of people
everywhere." - Dr. William H. Stewart, former U.S. Surgeon General.
At six a.m. I am awakened by my
neighbor revving the engine on his old pick up. At eight a.m, as I ride my
bike through rush hour traffic, all thoughts are drowned out by the constant
roar of passing vehicles. Around noon I try to have a conversation with a
friend while eating lunch at an outside cafÈ downtown. After five minutes of
yelling over the noise of an endless string of vehicles, we decide to move
inside.
Ok, by now youíve probably gotten the idea. Vehicles are
loud and annoying and they disturb everything from your ability to sleep to
your ability to think or simply enjoy some time in the sun. But what you
probably didnít realize is that vehicle noise pollution has been found to
cause everything from high-blood pressure and stress to migraine headaches and
even birth defects. Or, that while the normal level of hearing for humans is
between 0-25 decibels (dB), the average roadway noise is around 85dB, slightly
above what many researchers have found to be considered "dangerous."
While noise pollution has been found to cause a number of
disturbing effects on the health of society, it has continued to be one of the
most overlooked issues by the media and our society as a whole. We can only
speculate as to the real reasons for this. We can blame the automotive and oil
industries for spending millions to convince us that we need a vehicle,
thereby decreasing our ability to be concerned about such an issue. After all,
how could something so necessary produce something so negative? Another
reason, that might be a bit easier for the masses to accept, might be that
while pollution of the air and water is disturbing to the eye, noise pollution
has no visible impact. Also, with visible pollution, the direct correlation
between cause and effect is easy to detect. The roar of traffic, honking horns
and revving engines are not as easy to see or feel, compared to brown haze and
burning lungs.
Stress
Researchers have found vehicle noise pollution to be a major
cause of stress. Stress, however, has become so prevalent in todayís society
that it becomes difficult for the average citizen to become concerned about
stress caused by vehicle noise pollution or to see their stress as a direct
result of vehicle noise pollution.
The truth remains though, that noise is a powerful source of
stress. It is true that some sounds may be found to be soothing and joyous, such
as certain music or the sound of songbirds. But we donít need an opinion poll
to find that for the vast majority of us (even those that cherish their Ford
Expeditions) vehicle noise pollution is not considered relaxing, but instead is
annoying, or at the very least, unwanted. And research shows that our body
perceives noise that is considered ëunwanted or intrusiveí as a threat or
warning. And even if the noise is not a threat or warning, biological changes
still occur and strong stress reactions are triggered. Stress reactions include
the release of several stress hormones, changes in heart rate and rhythm, rise
in blood cholesterol levels and digestive upsets. It becomes easy then to see
how vehicle noise pollution can be traced to a multitude of stress related
illnesses.
Among these is high-blood pressure. When people are exposed
to an unwanted or intrusive noise on a consistent basis, they are put into a
near constant state of agitation, with an accompanying increase in blood
pressure. What this implies is that, although you might feel like it, you do not
become immune to the noise pollution or the effects of it. You might feel as
though you have become used to it, but your body is still reacting in the same
manner. If this condition persists, it will have the effect of high-blood
pressure. Since researchers have consistently linked long-term exposure to noise
pollution and high-blood pressure, noise pollution has been deemed a possible
cause of such cardio-vascular diseases as heart disease.
Another side effect that researchers have linked to stress,
induced by vehicle noise pollution, is a weakened immune system. For years
researchers and doctors alike have been finding a growing correlation between
the health of oneís immune system and the level of stress he or she is exposed
to. When stress hormones are released during prolonged exposure to something
like vehicle noise pollution, our immune systems are negatively impacted.
According to a study conducted at the University of Utrecht, The Netherlands,
"uncontrollable stress induced by noise pollution produces high levels of
cortisol, which suppresses immune system functioning and may have a prolonged
detrimental effect for health." This can be especially critical for those
with already weakened immune systems such as those with AIDS or cancer.
Birth defects
Even more troubling is the effect that vehicle noise
pollution can have on the unborn. Because the unborn are not completely
protected from environmental noise, nor from their motherís response (stress)
to noise pollution, they essentially react in the same manner as the rest of us.
The American Academy of Pediatrics reported in a study from 1997 that
"exposure to excessive noise during pregnancy may result in high frequency
hearing loss in newborns, and may by associated with prematurity and
intrauterine growth retardation." Loud or abrupt noises have also been
found to disturb the fetus directly, causing an increase in heart rate. A most
critical time in which irreversible developmental problems can occur is within
the first 14-60 days after conception. Since this is when central nervous system
and vital organ development is taking place, disturbances during this time can
lead to birth defects and low birth weights. Studies have also shown that stress
(as a product of noise pollution) causes the constriction of uterine blood
vessels which supply nutrients and oxygen to a developing baby. Being deprived
of these vital elements could undoubtedly lead to complications in birth.
Effects on hearing
Not all the effects of vehicle noise pollution are related to
stress, however. Millions of citizens worldwide are hampered by hearing loss,
much of which is sound induced. A quick description of how the ear works is
necessary at this point: When noise reaches the inner ear it is transduced by
hair cells, which line the inner ear, into nerve impulses and then is
transmitted to the brain, where it is perceived as sound.
There are essentially two ways in which sound induced hearing
loss occurs: short term exposure and long-term exposure. Short term exposure
refers to loud bursts of sound that exceed 120dB (threshold for pain), such as
rock concerts or gun shots. Fortunately, this hearing loss is often only
temporary.
Such is not the case, however, with long term exposure.
"Hearing loss due to prolonged noise exposure is generally associated with
destruction of the hair cells of the inner ear. The number of hair cells damaged
or destroyed increases with increasing intensity and duration of noise and, in
general, progressive loss of hair cells is accompanied by progressive loss of
hearing." (World Health Organization, Sweden 1995) One then, cannot simply
expect that by disappearing into the silence of the forests for a while, the
effects of hearing loss will be reversed. Once the hair cells are destroyed,
they do not grow back, and your hearing will never be what it once was.
According to the Environmental Protection Agencyís Office
of Noise and Abatement Control (which disappeared during the Reagan
Administration) in order to protect from hearing loss, one should not be exposed
to more than 70 dB for an extended period of time. Meanwhile the average city
traffic is 85 decibels and in larger cities like New York, the noise level often
exceeds 90db. Les Bloomberg, director of Noise Pollution Clearinghouse in
Montpelier Vermont, has stated that "87% of Americaís city dwellers are
exposed to noise so loud it has the potential to degrade hearing capacity over
time."
It is therefore imperative that we continue to push for a
decrease in vehicle travel to reduce vehicle noise. Because we cannot expect
everyone to want to ride ten miles to work, however, we must not only push for
an increase in bike lanes and mass transit, but also for intelligent
development. This development should encourage the increase of mass transit,
bike, and foot travel, through proper planning and zoning, as well as the use of
parks and increased vegetation to decrease the amount of noise.
As an example, Boulder, Colorado comes to mind. Parks and
green spaces are dispersed throughout the city, and I didnít have much trouble
navigating my way around town on bike. And from what I could gather, the mass
transit system is effective (thatís saying a lot for a mass transit system in
the United States) and only seems to be getting better. Most importantly (for
the purpose of this article), it was probably the quietest city of its size that
Iíve visited.
We must create a society and lifestyle that caters to the bike and walking,
and not to the steel beast. We must make urban sprawl a thing of the past and
instead concentrate our growth in an intelligent manner. Stop building
intimidatingly wide roads with no sidewalks through subdivisions and then
connecting each subdivision with downtown by means of superhighways. Instead,
widen the sidewalks and bike lanes and narrow the roads. Intermingle places of
commerce with places of residence so getting a quart of milk isnít a six-mile
trip. Reestablish the idea of parks and green zones to be used as buffers
against noise. Replace the parking meters with trees and the parking spots with
shrubbery. Turn the parking lots into parks and put a bus stop at every one.
Beginning to sound like a bit of a dream? Well, hey, only about a hundred years
ago, so was the idea of a car.
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