Eleven Democratic senators led by Sen.Jeff Merkley, D-Ore., have written Agriculture Secretary Sonny Perdue that food labels indicating genetically modified ingredients should consist of clearly worded, on-package text labels rather than digital or electronic labeling, even though the law allows that.

"All Americans have the right to know what is in their food and how their food is produced," the senators wrote in a letter to Perdue.

"We are writing to urge you and the Agricultural Marketing Service (AMS) to consider carefully the rights and will of the American people as the AMS undertakes a rulemaking process to develop a national standard for clear, accessible labels for food products containing bioengineered (GE) ingredients."

"We also urge you to consider, and work to address, the obstacles Americans would face while attempting to access GE ingredient information through digital or electronic disclosures," the letter said.