Exposure to a common weed-killer may increase the risk of a rare nasal birth defect, according to a new study.

Researchers found that exposure to the most commonly used herbicide in the U.S., called atrazine, which is typically used in corn crops, increased the risk of choanal atresia in newborns, according to a study published in The Journal of Pediatrics.

Choanal atresia is a rare disorder that affects about 1 in 7,000 live births, where tissue forms and blocks the back of the nasal passage, affecting one or both sides of the nasal airway.

While the condition is rare, it can be serious because it can interfere with a baby's ability to breathe. Babies born with choanal atresia blocking both sides of their airway may suffer breathing failure and require resuscitation on delivery. The condition is usually treated through surgery to remove the tissue blocking the nasal passage.

Researchers studied the link between choanal atresia by examining the Texas Birth Defects Registry. They found that women who lived in the counties with the highest levels of estimated atrazine application were 80 percent more likely to give birth to a baby with choanal atresia or choanal stenosis, the less severe form of the disorder, compared to women who lived in counties with the lowest levels of atrazine use.

Lead researcher Dr. Philip Lupo, assistant professor of pediatrics - hematology/oncology at Baylor College of Medicine and Texas Children's Cancer Center, said that while very few risk factors for choanal atresia have been identified, he believes that chemicals, like atrazine, that disrupt a mother's hormone system are associated with the increased risk.

"One exposure that tipped in the direction [of atrazine] was maternal use of thyroid medications during pregnancy - there's a hypothesis that hormones, and in particular, thyroid dysfunction, are related to choanal atresia risk," Lupo told FoxNews.com. "We know through literature that atrazine is a suspected endocrine disruptor that alters endocrine activity and normal thyroid levels."

Atrazine may affect the endocrine system by copying the activity of certain hormones in the body, thus blocking their activity and disrupting normal biological processes. While the latest findings were significant, researchers stressed that more research is needed before making any new policy recommendations.

"Our results warrant more detailed exploration before any public health or policy-related recommendations are made, but this study is a good first step in trying to understand the origin of this birth defect, including a possible role of atrazine," Lupo said in a university news release.

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