Herbicide Associated with Birth Defects in Infants
Atrazine — Banned in EU but Used in US — Linked to Gastroschisis
Atrazine, an herbicide that is dumped in quantities of 80 million tons a year across crop fields and residential lawns in the United States, has been blamed for turning male frogs into females, causing prostate and breast cancer in mice, and forcing communities to spend millions of dollars to treat chemical-tainted water.
Photo by sabianmaggy
Now it looks like atrazine could be blamed for one other problem: gastroschisis in infants.
Gastroschisis — a birth defect where the intestines grow outside of the body — remains one of the most unexplained birth defects. But according to a study presented last year at the Society for Maternal-Fetal Medicine's annual meeting (aka, The Pregnancy Meeting), women who live less than 25 kilometers from surface water with a high concentration of atrazine have babies with gastroschisis much more frequently than women who live farther away. And in a finding that has been corroborated in other studies, the researchers noticed a higher number of babies born with gastroschisis who were conceived in the springtime, when chemicals like atrazine are sprayed the most heavily.
The researchers acknowledge that the link between atrazine and the prevalence of gastroschisis in infants is far from proven. At this stage of the research, scientists have demonstrated an association between the chemical and gastroschisis. But the herbicide’s main producer, Syngenta, has repeatedly denied any detrimental effects of atrazine, citing studies that the Environmental Protection Agency used in its decisions to reapprove atrazine in 2003 and 2006.
According to the company’s website: “Syngenta ensures that residues of atrazine and all our crop protection products in water do not pose a health risk for consumers and that they are within the limits defined by authorities.”
But even at concentrations below the EPA regulation of three parts per billion, scientists have documented adverse effects of atrazine on amphibians and other animals. The possible link to gastroschisis is just the latest in a series of health and scientific concerns about the herbicide’s safety.
“The association between agrichemical exposure, seasonal variation, and increased risk of gastroschisis is consistent with previous studies. Our results endorse these findings, with a clear trend towards an increase in the rates of gastroschisis in the springtime,” the new study states.
This study, done by University of Washington scientists, observed that the state of Washington, which is largely agricultural, “has up to 2.2 times the number of observed to expected cases of gastroschisis, compared with US vital statistics.” Similarly, a study in 2007 by Paul Winchester, a doctor at St. Francis Hospital in Indianapolis, showed a slight increase in the cases of babies with gastroschisis who were born in May and June, when atrazine levels in the water at the highest.
Another study in 2009 by Winchester showed the rate of all birth defects was 3 percent higher for babies conceived in April through July. The researchers also found an increase in 11 specific defects during those months — including gastroschisis, which occurred 4 percent more often in April through July than in other months.
Unlike other birth defects, gastroschisis has been on the rise in recent years, which could point to an environmental cause for the condition. But so far, there has been no significant change in how the herbicide is distributed in the United States. The European Union banned the chemical in 2003, the same year it was reapproved for use in the United States.