Manufacturers can add up to 0.7 mg of folic acid per pound of corn masa flour.

WASHINGTON — The Food and Drug Administration on April 14 approved folic acid fortification of corn masa flour. Under the new rule, manufacturers will be able to voluntarily add up to 0.7 mg of folic acid per pound of corn masa flour, consistent with the levels of certain other enriched cereal grains.

The F.D.A.’s ruling comes four years after it received a petition sent by a coalition of six organizations — Gruma Corp., Royal DSM N.V., the March of Dimes Foundation, the Spina Bifida Association, the American Academy of Pediatrics and the National Council of La Raza — requesting such a measure take place.

Folic acid, a synthetic form of folate, is a B vitamin that when taken by a pregnant woman may help prevent neural tube defects, which are birth defects affecting the brain, spine and spinal cord. Pregnant women with folate deficiency have a higher risk of giving birth to infants affected with neural tube defects.

Corn masa flour, sometimes called masa (Spanish for dough), is produced by cooking corn in alkali and then grinding it. Corn masa flour is a staple food for many Latin Americans. It may be used to make foods such as tortillas, tortilla chips, tamales, taco shells and corn chips.

Currently, manufacturers may use folic acid as an optional ingredient at specified levels in breakfast cereals and certain other foods, such as infant formula and medical foods, so that it is easier for people to get enough folic acid in their diets. Since 1998, the F.D.A. has mandated folic acid fortification of enriched grains in the United States. Since then, the number of babies born in the United States with neural tube birth defects has declined by about 36%.

Susan Mayne, Ph.D., director of the F.D.A.’s Center for Food Safety and Applied Nutrition

“Increased consumption of folic acid in enriched flour has been helpful in reducing the incidence of neural tube defects in the general population,” said Susan Mayne, Ph.D., director of the F.D.A.’s Center for Food Safety and Applied Nutrition. “Our analysis shows that adding folic acid to corn masa flour will help increase the consumption of folic acid by women who consume this flour as a staple in their diet.”

The F.D.A. may approve the use of a food additive only after conducting a scientific safety review of the information provided in the petition to ensure that the additive is safe for the general population. With regard to folic acid, the F.D.A. said it evaluated the projected human dietary exposure, toxicological data and other relevant information, including whether folic acid remained stable in corn masa flour.

The F.D.A. said it worked with the petitioners throughout the review process to obtain data needed to address safety questions as expeditiously as possible. Based on that data, the F.D.A. concluded that the petitioned addition of folic acid to corn masa flour at a level not to exceed 0.7 mg of folic acid per pound of corn masa flour is safe.

Jennifer L. Howse, president of the March of Dimes

“Today’s announcement represents a major victory for maternal and child health, especially in our Hispanic communities,” said Jennifer L. Howse, president of the March of Dimes. “The F.D.A.’s decision will prevent numerous cases of devastating birth defects like spina bifida. The March of Dimes and our partners applaud the F.D.A. for moving forward with this vital public health effort.”

Being a socially responsible company and caring for the nutrition of its customers has been a directive of Juan Gonzalez Moreno, president of Gruma Corp.

“We will continue to honor and contribute to these initiatives and will put our best efforts to deliver the higher quality and improved nutrition that folic acid will bring to our Hispanic customers in the U.S.,” Gruma said.