Dan Bradley was appointed the director of pari-mutuel wagering in Florida two years ago. Having spent much of his professional life as a lawyer in Washington, and having never seen a horse race, he hardly knew what to expect.

But he learned quickly. Bradley found that dealing with the politics and the economics of racing was only a small part of his job. The most important matter was chemistry, for the most important fact about racing was the proliferation of illegal drugs.

When Bradley leaves his post next week to return to his work here with the Legal Services Corp., he will do so with a sense of enormous frustration.

"The drug problem," he said, "frustrated the hell out of me."

Bradley came into the racing world at a time when Florida, like Maryland and most other states, was liberalizing its medication rules. The rationale for the changes was that the advent of year-round racing had placed much greater stress on the thoroughbreds, who now needed painkillers like Butazolidin to keep them in action. And after Bute was widely accepted, the diuretic Lasix was legalized by many states.

"We've been chipping away at the prohibitions until now in Florida we've got a four-page list of the medications that you can use," Bradley said. "If every horseman was one of the 12 disciples, permissive medication might work. But the trainers and vets know that they can use the legal ones and beat our chemists.

"They can mix together a number of the legal drugs and then add an illegal stimulant or narcotic. When we get that urine sample back, I can ask the chemist" 'Doctor, what's in it?' but it's impossible for him to tell me every substance that's there. Fifty chemists can't do it. It's like dropping you in the middle of the Sahara Desert and telling you that there's one grain of sand that will destroy the universe and you've got to find it."

Even though the use of illegal drugs has reached near-epidemic proportions, Bradley said, "State regulatory bodies have not been conscious of what's going on. In the Florida laboratories, we had the same number of chemists as we did 10 years ago."

The chemists in their testing procedures cannot keep pace with the development of new, hard-to-detect drugs. Florida chemists did make headlines this winter when they found a number of horses who had raced with the narcotic Sublimaze, but this discovery may have represented only the tip of an iceberg.

"We've got over 2,700 urine specimens in a deep freezer and we know that something is in them besides Bute and Lasix," Bradley said.

The use of illegal drugs that concerns Bradley is hardly a phenomenon limited to Florida. The racing in that state seems very logical and formful, in fact, compared with other places, such as Maryland and Kentucky. Yet as widespread as the problem is, Bradley has been one of the few racing officials to address it.

He hopes he has managed to stir some debate on the subject within the industry.

"It's important for owners, trainers, bettors and the media to discuss and argue the subject," he said. "I'm no ideologue. If people feel the only way to have year-round racing is to have permissive medication, I can understand that argument.

"But if you take that posture, you have to understand the consequences of the decision. And one of the consequences is this: Our job is to protect the racing public, and we cannot do it now."