In 1991 portions of Texas’s Rio Grande Valley saw an upsurge in babies born with neural-tube defects. Litigation resulted:
Residents and lawyers had blamed pollution, and General Motors and other U.S.-owned factories paid $17 million without admitting wrongdoing to settle a lawsuit accusing their border factories of poisoning the air.
The claimed linkage of cause and effect between the factory pollution and the birth defects was, to say the least, much controverted at the time, and is looking even less impressive in hindsight:
no chemical links to the disease were ever proven, and Texas health officials began suspecting fumonisin, a toxin in corn mold. Experts had noted a high concentration in the corn harvest just before the outbreak. Some Texas horses died from brain disease caused by the toxin.
Now, a study in the February issue of the journal Environmental Health Perspectives adds impetus to the corn-mold theory:
The study found that pregnant women who ate 300 to 400 tortillas a month during the first trimester had more than twice the risk of giving birth to babies with the defects than did women who ate fewer than 100 tortillas.
Blood samples indicated that the higher the level of fumonisin, the greater the risk of neural tube defects.
Tortillas are an inexpensive dietary staple along the Texas-Mexico border, and studies suggest that the average young Mexican-American woman along the border eats 110 a month.
(“Study: Bad corn caused birth defects”, AP/Seattle Post-Intelligencer, Feb. 8). See also Dallas Morning News, Mar. 4, 2001; AP, Jan. 2001; Nicole Foy, “Border birth defects are tied to poverty”, San Antonio Express-News, Apr. 9, 2004.
Among its other implications, the episode may suggest the safety gains to be had in the shift from a pre-modern food regime based on local farm and home production to the sort of industrially based food regime more familiar to most Americans. Even aside from the issue of folic acid fortification, a big-city tortilla factory run by a large company would probably have had a better likelihood of screening out moldy batches of corn.