Lisa Dry, a spokeswoman for the Biotechnology Industry Organization, said Tuesday the companies changed the policy "because we did not want to appear to encourage discrimination against certain parts of the country."
Companies are producing enzymes and proteins used in pharmaceuticals by growing them in genetically modified corn. A dozen companies that are members of the biotech group agreed in October to stop growing such crops in corn-belt states in 2003, saying they wanted to build the public's trust that they could grow them without contaminating crops grown for food.
But the new policy said: "Detailed scientific and regulatory analyses confirm that plants that produce pharmaceutical and industrial products can be safely planted, grown and harvested in an agricultural region where all of the appropriate production, confinement, and handling practices are implemented."
Dry declined to elaborate on the change. But Andrew Baum, president of SemBioSys, a Canada-based biotech company that is a member of the group, said the revised policy is really a clarification of the moratorium.
"It's not a fundamental change in what any of the companies are going to do," Baum said. "I don't think any companies have backed away from their commitment to ensure that we don't create a problem for the food supply."
Carl B. Feldbaum, the group's president, sent a copy of the new policy with a letter Monday to Sen. Charles Grassley, R-Iowa, saying the organization hoped to work with Grassley "to make the economic rewards of this and other new uses of biotechnology become a reality in Iowa as rapidly and as broadly as possible."
Grassley said in a statement that the biotech organization is making a good move by revising its policy.
"Iowa should be much better served with the new position BIO has taken," Grassley said. "It's good to see that BIO has realized that they are putting unscientific restraints on Iowa and many other states."
Environmental groups such as Friends of the Earth say pharmaceutical crops should not be grown at all.
"Not only is this brand of science for profit wildly ill-advised, it's sure to lead to a plate full of food rife with chemicals that ought to be on a druggist's shelf or in a chemical plant - not in a grocery store," said Mark Helm, a spokesman for Friends of the Earth.
By Emily Gersema