Americans have always viewed medical research as a sacred calling. We think of Jonas Salk laboring into the night on a polio vaccine or Alexander Fleming discovering the wonder drug penicillin. It all seems so noble.

What's missing from this picture? Millions of dollars in research fraud by con artists in lab coats who take federal grants and fake their findings for money or for ego.

Honest research and your tax dollars are endangered by hanky-panky on grants totaling millions of dollars. The government regularly traces the paper trails of researchers on its payroll, looking for such con games.

Ego and greed can short-circuit scientific inquiry. Some scientists fake results simply so they can look productive and stay on the government gravy train.

Only the celebrated cases get news media attention. The most recent example is John Ninnemann, whom the government has accused of falsifying reports in connection with $1.2 million in grants from the National Institutes of Health. The Justice Department recently joined a private lawsuit against Ninnemann to recover the money.

Ninnemann is alleged to have faked the results of his study on how the human immune system is affected by burn injuries. Two universities that signed off on his work are also named in the suit.

The details are under seal in a federal court in San Francisco. The government has revealed that the suit was originally filed by a former assistant of Ninnemann's under a federal law that allows a 15 percent finder's fee for those who successfully sue claiming the government has been defrauded.

For as little as the bureaucracy says about these cases, one would think the Ninnemann case was an isolated incident. It is not.

The NIH is the government's premier medical research agency. At any given time, its investigators are looking into 70 cases involving allegations of research fraud by scientists who are using NIH money. NIH spokesman Don Ralbovsky told our associate Dan Njegomir that the current caseload is about 75.

How much of your money is at risk in those cases? The NIH says it's hard to nail down a dollar figure because not all of the cases involve a flat-out rip-off of all of the grant money, and not all of the allegations turn out to be true. Still, given that the average NIH grant is $85,000, a conservative estimate is that $6.3 million in federal research money on the average is under scrutiny at any time.

The scientific community is loath to acknowledge thieves in its ranks, but legitimate researchers fear the implications for science. A publication by the Association of American Medical Colleges notes that even a handful of bogus research projects "may undermine the scientific enterprise in ways that go far beyond the waste of public funds."

A series of seminars by scientists over the last decade has resulted in guidelines for investigating phony research. NIH's Office of Scientific Integrity has grown from one person to 12 in recent years.

Even for a dozen people, the work is daunting. NIH spends $7.6 billion a year, and 80 percent of that goes to grants that must be monitored like a merchant watches for common shoplifters.