Two medical researchers who have worked for six years with animals and humans at the Yale University School of Medicine claim that "recreational" sniffing of the illegal drug cocaine is no more habit-forming or threatening to health than are small doses of alcohol or tobacco.

"The pattern of [cocaine use] behavior is comparable to that experienced by many people with peanuts or potato chips," Drs. Craig Van Dyke and Robert Byck write in the March issue of Scientific American magazine. "It may interfere with other activities of the individual, but it may be a source of enjoyment as well."

On the other hand, Van Dyke and Byck say, heavy use of cocaine by smoking or injection can be so harmful that the drug becomes "enslaving," forcing the user to prefer the drug over anything else in life.

"When a drug like this is overused, it can be intensely destructive in the sense that a user's entire life structure may change," Byck said in a telephone interview. "When cocaine is taken regularly, it can cause sleeplessness, loss of appetite, hallucinations and paranoia. Injected cocaine or smoked cocaine can make users so enslaved it can destroy lives."

In experiments with 30 cocaine users and at least as many monkeys over a six-year period, the two researchers found that "recreational" users of cocaine who "snort" the drug through the nose feel effects that differ dramatically from those experienced by users who frequently inject it into their veins or smoke it in its pure powder form in what is called "free base."

So fleeting and so mild are cocaine's effects, Van Dyke and Byck report, that most recreational users cannot tell the difference between cocaine and other drugs such as lidocaine (Xylocaine), procaine (Novocaine) and even some placebos such as sugar and talc that in their powdered form resemble cocaine.

"Our subjects, all experienced cocaine users, could not distinguish a single dose of cocaine taken intranasally from the same quantity of the synthetic local anesthetic lidocaine," they write. "Such results are the first steps toward distinguishing the almost overwhelming mythology that surrounds cocaine from reliable information about its effects."

The two doctors said cocaine users may be paying $100 a gram for a drug that ranges from zero to 50 percent cocaine. Much of the cocaine being sold to users may be like bottles of cheap wine sold as vintage wine to those who cannot tell the difference, they said.

"It's clear to us that the cocaine on the street has been cut tremendously, especially with local anesthetics like procaine," Van Dyke said. "The only way users can test the stuff they're getting is by tasting it, and procaine will momentarily deaden the tongue and lips just like cocaine. There's no way people can tell the difference."

Despite the devastation caused when cocaine is smoked or injected, Van Dyke and Byck concluded that recreational use of the drug through the nose is neither addictive nor harmful.

"Cocaine users can take the same dose every day and get the same effect," meaning they do not gain a tolerance to the drug as do users of opiates, barbiturates and even alcohol, they write.

"There are withdrawal signs . . . but they are quite undramatic when compared with the withdrawal syndromes associated with opiates, barbiturates or alcohol," they write.

They conclude overall that "a considerable bureaucratic constituency depends for its existence on the public belief that cocaine is unequivocally pernicious. It is not clear whether the potential for the abuse of cocaine justifies the intensity of such efforts.

"The main threat from cocaine is the waste of human potential that could result from widespread consumption. Cocaine policy and regulations take little account of these conclusions."