TUCSON, Ariz. - The racing industry should welcome additional studies into threshold levels and withdrawal times for medications that are commonly used in the sport, but the public has a hard time understanding the concepts because of the use of several misleading terms when discussing drug positives, several racing chemists and veterinarians said on Thursday at the University of Arizona's Symposium on Racing and Gaming here.\nDr. Rick Arthur, the equine medical director of the California Horse Racing Board, and Dr. Rick Sams, the director of the racing laboratory at the University of Florida, both took issue during the panel with the use of the term "zero-tolerance" in articles and discussions about drug testing, claiming the term was meaningless and politically loaded. In addition, panelists also objected to the use of the term "trace levels" when referring to concentrations of drugs in post-race samples because of wide variations in the criteria of what would constitute pharmacologically significant concentrations among medications.\nThe comments by the officials underline the sometimes vast disconnect between racing participants and the scientific community on how to deal with positive post-race tests for illegal medications. Just in the past two weeks, two high-profile trainers, Kiaran McLaughlin and Tom Albertrani, have accepted 30-day suspensions from Kentucky regulators for what the trainers called "trace levels" of regulated medications. In reporting the positives, several media accounts, including an article in Daily Racing Form, used the term "zero-tolerance" to characterize the regulatory scheme governing the drugs.\nArthur said that the term "zero-tolerance" is meaningless because all testing laboratories and methodologies have self-contained limits on the concentrations of drugs that they can accurately detect. In other words, many post-race blood and urine samples contain concentrations of drugs that are never called positives because they are never detected.\n"The fact of the matter is that there is no such thing as zero-tolerance," Arthur said. Because of those self-contained limits, Arthur said, every drug used in racing has a threshold level, "whether it is set deliberately or in the laboratory."\nThrough scientific studies, the racing industry has established threshold levels for roughly 20 medications, including anabolic steroids, in an effort to set limits on the concentration of a drug that can appear in a horse's post-race blood or urine samples so as to allow veterinarians and horsemen to administer therapeutic medications to horses outside a certain number of days within a race. The research to establish those levels has accelerated in recent years with the advent of the Racing Medication and Testing Consortium, an industry-funded group that directs a substantial part of its budget toward research into drugs.\nThe studies to establish those limits are "very, very hard to do," according to Dr. Robert Lewis, a prominent equine veterinarian and a past president of the American Association of Equine Practitioners. However, Lewis said, the results of the research provide wide benefits to trainers and veterinarians by establishing a guide that protects honest horsemen from those that may be seeking an edge in a race or when training.\n"It's hard to hide from the science if the science is good," he said.\nDr. Heather Knych, a specialist of equine pharmacology at the University of California, Davis, who has conducted studies into the effects of medications, said that analyses of how drugs affect horses are complicated by wide variations in the physical reactions to medications in horses targeted for the study.\nLewis said that although some horsemen vociferously complain about being caught for concentrations of drugs that purportedly have no pharmacological effect on the horse at the time of the race, the racing industry is best served by "erring on the side of caution."\n"That's how you protect the integrity of the race, the integrity of the sport," Dr. Lewis said.\nArthur backed up that statement by showing a video of the 2009 Breeders' Cup Marathon, in which the first two finishers were separated by a nose after running 1 3/4 miles.\n"You tell me whether a small concentration of a drug had an effect on a race like that,". Arthur said. "If you're the second-place finisher and the winner has that small concentration, what would you think?"\nRacing urged to offer more free content\nAlso on Thursday, specialists in social media said that racetracks and their publicists should embrace new developments on the Internet and among mobile devices in order to expand their reach and empower their fans.\nDr. Holly Kruse, an assistant professor in communications at the University of Tulsa who described herself as a racing fan, said that "horse racing's problem is its visibility. It's invisible."\nTo improve its standing, racing needs to offer its fans free content such as videos and racing data, so that those fans can create new messages from the content and reach out to a wider audience.