http://www.biomedcentral.com/news/20030528/03

Treasure trove of toxins

Scientist warns that pharma industry's castoffs could be source of new chemical weapons

By John Dudley Miller
 

United States pharmaceutical companies are inadvertently creating tens of thousands of poisonous new compounds each year that terrorists or rogue nations could develop into chemical weapons, according to a California researcher.

These unintended toxins arise from the drug industry's automated high-throughput technology that permits millions of new compounds to be created and tested, and those found to be toxic to humans, simply discarded, said Mark Wheelis, director of the Program in Nature and Culture at the University of California, Davis.

"Currently, a single [facility] can screen several hundred thousand new compounds per day against several dozen different proteins," Wheelis said. Of three million new compounds created each year, on the order of 50,000 are highly toxic, he explained. "Any one of these is a potential lethal chemical weapon agent."

The International Committee of the Red Cross (ICRC) is also concerned about these and many other products of the biotechnology revolution that have dual helpful and harmful uses, noted Tamas Bartfai, professor of neuropharmacology at the Scripps Research Institute. Last September ICRC issued an appeal "to governments and pharma companies that they should start to think about guarding what they do," he said.

Experts disagree about how easy it would be to steal databases of unintended toxic drugs. As trade secrets, "It would be tough for [bad guys] to get access to it," said Steven Block, professor of applied physics and biological sciences at Stanford University.

Bartfai strongly disagreed. "Of the toxic ones today, nobody keeps track, just nobody." The best example, he said, is angel dust, the illegal drug PCP. That was inadvertently made during a drug company's research into glutamate receptor ligands, he said. Discarded because of its psychomotor side effects, it was left unguarded, and it's been sold on the street ever since.

Wheelis acknowledges his critics' point that considerable research would still be required to turn inadvertently-manufactured poisonous chemicals into effective, deliverable weapons. He is much less concerned about the 50,000 annual pharma industry toxins than he is about a government using its own screening machinery to develop poisons from scratch.

Matthew Meselson, Thomas Dudley Cabot Professor of the natural sciences at Harvard University, believes that unintended poisons pose no threat whatsoever. Publicly available chemical databases already describe thousands of easier-to-develop toxins, he said, so why should wrongdoers look any further?

Enemies needn't bother with new toxins because we can't even protect ourselves against old ones, added Block. "As things stand," he said, "we don't have good antidotes or ways of dealing with the toxins that we already know about."