AUGUSTA, MAINECitizens on the West Coast have led ballot initiatives to require labels on genetically modified foods. But the Northeast actually has laws on the books.

Maine this week joined Connecticut to become the second state with a law governing GMOs (genetically modified organisms) after Maine Gov. Paul LePage "symbolically" signed the bill.

Food companies need not scramble to change their labels. Maine's law doesn't take effect unless legislation requiring mandatory labeling of GMO food has been adopted in four other states in the Northeast. Connecticut's law has similar requirements.

"American consumers want the right to know what is in the food they eat, plain and simple," said Rebecca Spector, who spearheads state GMO labeling legislative efforts at the Center for Food Safety, the non-profit advocacy group. "The food movement has created the political will to label genetically engineered foods and states are beginning to respond."

Adrienne Bennett, press secretary for Gov. LePage, said the governor on Wednesday allowed L.D. 718 ("An Act to Protect Maine Food Consumers' Right to Know about Genetically Engineered Food") to become law. 

Through the legislation, Maine lawmakers aimed to promote food safety, enable consumers to make informed decisions and create opportunities for producers whose food is not genetically engineered.

The law would require the label "Produced with Genetic Engineering" for food that is offered for retail sale and has been genetically engineered. Restaurants, alcoholic beverages and medical food are exempt from the required disclosures.

California and Washington voters have rejected ballot measures. But a number of state legislatures across the United States have introduced GMO labeling initiatives.

Supporters of such labels say consumers have a right to know what is in their food.

There is no federal requirement to label genetically engineered foods.

The U.S. Food and Drug Administration (FDA) has maintained that GMOs are safe, though critics question their safety and impact on the environment. 

Led by the likes of the Grocery Manufacturers Association and Monsanto Company, the bioengineering giant whose seeds are widely used by farmers, the food industry has complained that mandatory GMO labels would drive up costs for manufacturers and lead to more expensive groceries.  

Others including Whole Foods Market and Ben & Jerry's have expressed support for GMO labels.