Here on Cape Cod, site of one of the eight North American Air Defense (NORAD) installations that sweep the sky, "radar" has become something of a dirty word.

Environmentalists and citizen groups throughtout the popular resort area have joined thousands of others nationwide in protesting "electronic pollution" that they claim is emitted by every type of microwave device, from ovens and citizens' band radios to television sets and military radar.

Wide publicity has been given the possible dangers to U.S. embassy personnel in Moscow from nearly two decades of microwave bombardment by the Soviets, and to reports of Minnesota farmers tearing down high tension power towers in fear of microwave radiation leaks. A new book called "The Zapping of American" charges that the dangers of microwave radiation have been covered up.

The nearly 200,000 residents of the cape (the population swells fivefold in the summer) have recently become aware that the Air Force radar unit near the tip of the peninsula has been enitting microwave radiation at populated areas over the past 20 years.

The Air Force has also nearly completed construction on a $55 million radar facility at Otis Air Force Base, near the point where the Cape borders the southern edge of the Massachusetts mainland.

Concern over the effects of microwave radiaton from these Cape Cod radar facilities increased with the publication of the "Zapping" book by New Yorker staff writer and part-time Cape resident Paul Brodeur. He alleges that microwave radiation can cause blindness, cancer, genetic damage and death.

His concern was passed on to local federal officials as well as the local press. The switchboard at Otis Air Force Base has been lit up with calls from worried residents.

The military says that neither the old radar unit nor the new PAVEPAWS (Precision Acquisition of Vehicle Entry Phased Array Warning System) has shown adverse physical or psychological impact on the population, and that radiation levels are "well within federal standards."

But local residents have not been assuaged by the Air Force argument that the local radar units are both safe and necessary for their defense.

"Of course the Air Force says according to their own investigations there is no harm, just as General Electric will say there's no harm to humans from microwave ovens and yet they had to recall 30,000 of them because they leaked radiation," said Howard Schneider, President of the Outer Cape Cod Environmental Association, one of three citizens' groups which called a hearing with Air Force officials here Wednesday night.

Rep. Garry Studds (D-Mass.), whose district includes Cape Cod, has said either the Air Force must prove that long-term exposure to low-level radiation does not endanger people or the military must cease construction of radar facilities.

"The most disquieting thing appears to be the simple and rather humbling fact that we simply don't know the answers, we do not know what is safe," Studds said after the hearing.

"If the Air Force cannot document to us that their claims are supportable by some kind of science evidence, then at the very least we're going to ask for a full environmental impact study with public hearings," he said."And if there are no answers, then with respect to PAVE PAWS we're going to ask the Air Force to hold off."

The New England Regional Environmental Protection Agency has so far said the PAVE PAWS project will cause no danger. Its 29-page evaluation of 22 sites on Cape Cod states: "At this time we are not aware of any adverse health effects due to exposure to levels of the magnitude expected to be produced by the PAVE PAWS operation."

Nevertheless, area scientists are quick to point out that the EPA report is based on what Harvard biology professor and novel laureate George Wald calls "the irrelevant assumption" that microwave radiation is only harmful if it burns human tissue.