Study links Louisiana pollution hotspots to higher infant heart defect odds

Researchers analyzed 454 infants and exposure to 20 toxins

A study published last week in the Environmental Health journal examined medical records for 454 infants hospitalized at two major Louisiana hospitals that provide surgery for heart defects in babies. Researchers traced back where the infants’ mothers lived and found that infants from southeast Louisiana’s highest industrial-pollution areas had 4.3 times the odds of congenital heart defects compared with infants from low-pollution areas.

Researchers used the US Environmental Protection Agency’s risk-screening database to compare levels of industrial toxic pollution in the mothers’ communities. The study found that infants from intermediate-pollution areas had 3.1 times the odds of congenital heart defects compared with infants from low-pollution areas.

The analysis covered infants born from 2018 to 2021 and examined mothers’ potential exposure to 20 toxins known to cause adverse health effects during early development, including benzene, formaldehyde and toluene.

Kelly Gajewski, a pediatric cardiologist at Manning Family children’s hospital and a professor at Louisiana State University Health Sciences Center, said a diagnosis of congenital heart disease can be life-altering for families. “I think the biggest part of it is that it is very anxiety-producing to have a baby that has congenital heart disease,” Gajewski said. When she moved to Louisiana more than a decade ago, Gajewski thought she was seeing more cases of severe congenital heart disease in children. “I had some suspicions that there was something in this state leading to higher rates,” she said. Those suspicions led her to explore environmental factors as possible contributors to the conditions.

Lead author Kimberly Terrell, a research scientist with the Environmental Integrity Project, said, “The study shows that the impact of industrial pollution on Louisianans’ health starts in the womb.” Terrell contrasted long-term health effects such as cancer and chronic obstructive pulmonary disease with developmental effects from shorter exposures. “We know that early in pregnancy is the critical window of heart development and also development of other body systems, so you have this pretty narrow three-month window where it’s really critical to reduce these exposures.”

The researchers excluded cases in which a mother was recorded as having smoked, consumed alcohol or had diabetes during pregnancy. “We wanted to focus on the births we would expect to be healthy,” Terrell said. “We can confidently say this risk is unattributable to smoking, alcohol or diabetes.”

Louisiana has among the highest rates of infant mortality and industrial emissions in the US. Previous studies have linked the state’s toxic air pollution to low birthweights and high cancer rates among Black and impoverished communities. Petrochemical facilities are the largest source of toxic pollution in the state.

The Centers for Disease Control and Prevention says a baby is born with a heart defect in the US every 15 minutes. The CDC also reported that about 15% of infants born with critical forms of heart defects do not survive their first year of life. Gajewski said a serious diagnosis can be life-altering, and parents of some of her patients move to New Orleans to be closer to the hospitals where their children receive care.

The study team included researchers and medical staff at the hospitals. Of the 454 babies with heart defects studied, 194 cases were severe and 38 babies died during the study’s timeframe. Gajewski said, “Although modern medical care can save the lives of babies born with serious heart defects, almost all of these children will continue to need specialized care and will face higher risks of learning disabilities, mental health disorders, heart failure, or other organ problems during their lifetime.”

The study team suggests that fewer babies in southeast Louisiana would be born with life-threatening heart defects if maternal exposure to industrial pollution were reduced. “If there’s political will, it can happen,” Terrell said.