Noise Pollution Takes Toll on Health and Happiness

A highly respected Dutch analysis combined the results from 43 studies that tracked chest pains, heart attacks and related problems with community noise levels. Using a statistical technique called meta-analysis, it concluded that there is "a slight increase in cardiovascular disease risk in populations exposed to air traffic and/or road traffic noise."

Face the Music

Even if chronic exposure to noise is unlikely to kill you, it can simmer under the surface and take a toll on your well-being.

Studies have shown that chronic night noise not only leaves you shrouded in a fog of fatigue, irritability and poor concentration, but also activates the stress response as you sleep. And while the number of awakenings per night may decrease as you adjust to the din, the increased heart rate, blood pressure and breathing changes persist.

"The idea that people get used to noise is a myth," the Environmental Protection Agency has reported. "Even when we think we have become accustomed to noise, biological changes still take place inside us."

The Health Council of the Netherlands found that high levels of mechanical noise, such as that from a hospital's own air-conditioning equipment, can delay recovery in patients -- a reflection, perhaps, of the immune suppression that comes with an activated stress response.

Another insidious effect of noise is its cultivation of what scientists call "learned helplessness." Children given puzzles in moderately noisy classrooms are not only more likely to fail to solve them but are also more likely to surrender early.

"They just give up," said Gary W. Evans, a professor of human ecology at Cornell University who studies noise and behavior. The implications of learned helplessness on a child's success in life "are potentially pretty powerful," he said.

Perhaps most disturbing in these times of political and economic polarization is that noise undermines generosity.

In one study, people were less likely to help someone pick up a bundle of dropped books when the noise of a lawn mower was present. Another showed that in a noisy environment, people playing a game were more likely to see their fellow players as disagreeable or threatening. Yet another found a drop in helpful behavior when loud "annoying music" was played.

Interestingly, helping behavior increased when similarly loud "uplifting music" was played. Which gets to the weird thing about noise: its mysterious psychological component.

Something to Yell About

Researchers still know very little about how attitudes toward noise affect its impact on health. It may be that people with upbeat attitudes -- people, for example, who do not believe that this blowhard up the street ought to be jailed -- will live longer, healthier lives than I will. After all, anger alone is a potent producer of stress hormones. Am I killing myself by caring?

Some research suggests so. People report being far less annoyed by noises they willingly accept or actively select (riding a motorcycle, for example) than by those they have no control over (the car alarm outside your window).

On the other hand, the hormonal systems of even the mellowest of people in noisy places may still be quietly seething.

After runway patterns were changed at an airport in Australia, researchers studied two neighborhoods -- one that was now noisier because of the change and one that got quieter -- both of which now had the same noise levels. People whose neighborhoods had become quieter were less anxious, angry and depressed than those whose neighborhoods had grown noisier. But the two groups' stress hormone levels were indistinguishable, suggesting that a good attitude may not be powerful enough to save you -- and a bad one won't necessarily kill you.

As an inveterate ranter against noise, I find that last point gratifying. It means I can complain as noisily as I want without losing the benefits of whatever quiet I win. ·

Comments:weissr@washpost.com.