ROANOKE TIMES
Copyright (c) 1995, Roanoke Times
DATE: Tuesday, December 5, 1995 TAG: 9512050082
SECTION: NATIONAL/INTERNATIONAL PAGE: A-1 EDITION: METRO
SOURCE: JOHN J. FRIED KNIGHT-RIDDER/TRIBUNE NOTE: Below
SCIENTISTS SUSPECT that continuous or high levels of sound raise blood pressure and even rob people of abilities and hope.
If it were only an occasional ringing telephone. Or just the telephone and, maybe, the drone of the traffic.
It doesn't stop there.
Computer keyboards clatter. When your colleagues aren't whining, the copying machines are.
It isn't any better at home.
The television drones. The refrigerator hums. The furnace or the air conditioner cranks on and off. Neighbors vacuum, mow or weed-whack at the oddest hours.
But is that noise more than a temporary annoyance or aggravation?
Hearing experts say that up to 30 million of us make so much noise in our homes or in our recreational activities that we risk serious hearing damage.
That, however, is about the most that can be said with any certainty about noise - even though there is widespread suspicion that too much of it can raise blood pressure, make nice people surly and stop children from learning.
And no one knows for sure because studies into the impact of noise pollution on mind and body are virtually nonexistent in the United States.
``We're stuck in the 1970s and '80s when it comes to [noise] research and knowing whether we are protecting people correctly,'' said Evelyn Talbott, an associate professor of epidemiology at the University of Pittsburgh.
Noise research may be in a 20-year holding pattern, but noise production is not.
The bottom line is that unless you live smack in the middle of a 40,000-acre Montana cattle ranch, you are one of 138 million people who, according to some estimates, are beset by all-too-many decibels.
Recreational noise, far more than noise in industrial settings, is the key villain that is making a lot of Americans go deaf, said James C. Saunders, professor of otolaryngology and neuroscience at the School of Medicine of the University of Pennsylvania.
Rock concerts, food processors grinding ice for margaritas, combustion-engine leaf mulchers, snowmobiles, target shooting, hunting and hobby room power saws emit a noise level that ``literally causes'' the hair cells responsible for transmitting noise to the brain to ``burn out,'' Saunders said.
The question, though, remains: Do the dull roar of traffic along an expressway, the clanking of a neighbor's wind chimes, the trash-chewing grinding of a garbage truck harm you?
Yes, some researchers say. The cacophony causes stress, increases blood pressure, raises the risk of heart disease and makes some of us more aggressive and less willing to help others, they say.
Other experts have their doubts.
``Junk science is rampant in this area,'' said David Lipscomb, the former head of the Noise Research Laboratory at the University of Tennessee and now a consultant in Stanwood, Wash.
Some people show a jump in blood pressure when exposed to noise, but that is not to say that the higher readings will necessarily translate into continuous and health-threatening hypertension, Lipscomb and others say.
And despite animal studies showing that noise affects heart function, it is impossible to determine how important that impact is in humans, said Jerome Singer, chairman of medical and clinical psychiatry at the Uniformed Services University of the Health Sciences in Bethesda, Md.
In studies he conducted with Los Angeles schoolchildren in the late 1970s and early 1980s, Gary Evans, a Cornell University professor of design and environmental analysis, compared blood pressure readings in poor and minority children living near Los Angeles International Airport with those of similarly deprived children living in quiet areas.
The children living near the airport had higher blood pressure readings.
Because Munich, Germany, recently closed an old airport, Evans got a shot at carrying out a before-and-after study of children who live near such facilities.
Those studies, Evans said, showed that children exposed to noise have higher-than-normal levels of epinephrine and norepinephrine, the hormones that increase blood pressure. That finding, he said, provides the physiological proof needed to link noise and blood pressure.
The Munich research also confirmed findings that children who are exposed to high levels of noise have trouble learning to read. The link between noise and reading problems is unknown, Evans said, though he has ideas.
One is that children continually subjected to noise have trouble recognizing speech. ``That may be linked to reading disorders, because you can't learn to read if you don't understand language,'' Evans said.
Evans and other researchers also say they think children bombarded by noise soon learn they have no control over it. That, in turn, imbues them with a sense of helplessness - one that may crop up in other areas of their lives.
LENGTH: Medium: 90 linesby CNB