Advocates are celebrating the nation's most sweeping legislation requiring special labels for genetically modified food.
But for the Connecticut rules to take effect, lawmakers in neighboring states will need to pass similar rules.
The Connecticut bill, which passed last week, calls for packaging on food that is entirely or partially genetically engineered to include the words "Produced with Genetic Engineering," but only after four other states enact a similar law.
This year, 28 states introduced proposals related to labeling of GMO food, even as action at the federal level has stalled.
Critics said genetically modified food, which results from seeds that are engineered in a laboratory, can lead to serious health conditions and harm the environment. But the federal government and many scientists say the technology is safe.