This article first was published by New England Post on October 26, 2011.

Beth Santoro of Billerica thought she did all the right things during her pregnancy. “I didn’t eat cold cuts for the listeria. I didn’t have caffeine. I avoided quite a few things,” said the stay at home mom and former preschool teacher.

According to a recent study published by the journal Pediatrics, Santoro may have unknowingly exposed her unborn daughter to bisphenol-A, or BPA, a chemical found in a variety of plastics. BPA became a household term in 2008 when the compound made the news with reports that it could be leaching into the contents of water bottles. The new study suggests that other types of containers deliver BPA into the body as well. The report links aggression, depression, and anxiety in very young girls to their exposure in utero.

“We’re primarily exposed through the diet because BPA is used for a lot of food contact material and processes,” said Joseph Braun, an environmental health researcher at Harvard School of Public Health and a co-author of the study.  The chemical can be found in food storage containers and in the tin cans’ linings used to prevent spoilage. He said that pregnant women should consider reducing consumption of canned or packaged foods.

“In my head I’ve always said, ‘It’s water bottles,’ ” said Santoro. “That’s what they were drilling into your head.” She was careful not to use old water bottles and to look for the BPA-free label. She said she was shocked to learn she had likely been exposing her unborn baby to BPA.

Santoro said she would have done things differently if she had had that information a year ago. “I would have probably bought the big jar of applesauce instead of the little prepackaged ones.” She said she looks back to all the yogurt, hummus, and applesauce she ate out of plastic containers.

However, Santoro said she does not generally eat many canned goods. “I do a lot of frozen vegetables rather than canned vegetables,” she said.

For many families, canned vegetables and beans represent a large portion of their diet. Braun recognizes that canned goods represent an affordable way to incorporate healthy food into the family diet. “So don’t get rid of those and start eating French fries and milk shakes.”

David Ozonoff, an environmental health professor at Boston University School of Public Health, said in a telephone interview that low-income families frequently are exposed to greater levels of pollutants. Ozonoff knew of no income-specific data relating to BPA, but he said it is highly probable that children in low-income families are exposed to higher levels of BPA both in utero and in early life.

Both Braun and Ozonoff pointed to cash register receipts as an unexpected yet significant source of BPA exposure. Braun suggested that the BPA can be absorbed through the skin when handling receipts. “They get thrown in landfills and get into the water and the environment, ” Ozonoff added.

Joseph Braun

Scientists have long suspected that BPA disrupts the body’s endocrine system, according to Ozonoff. “When the fetus is developing, especially the nervous system, there is a delicate choreography from one cell to another. In order to do this in a coordinated way, they have to talk to each other. One of the main ways they talk to each other is through chemical signaling—that’s the endocrine system,” he said.

He offered this example. “Imagine you go with friends to a crowded bar, and you’re sitting at a table trying to talk about something, but the band is playing. You’re not going to hear anything.” Endocrine disruptors create static-like noise that can lead to distortion and miscommunication and affect development, he said.

Braun said the study found that prenatal BPA exposure appeared to affect the development of “executive functioning” in the brain. “So when you sit down and you know you have to write a story, you have steps in your head, and you are able to plan how to carry them out,” he explained. “People with good executive function can manage those steps and know the order they should take. People with poor executive function can’t manage those types of tasks from start to finish.”

Some of the effects of BPA cited by Braun and his colleagues resemble the symptoms of Attention Deficit Hyperactivity Disorder, or ADHD. “Children with ADHD have difficulty in executive function. They are hyperactive, and they don’t know how to react in situations,” he said. He added, that the majority of the children in the BPA study had not been diagnosed with ADHD.

Braun’s study followed children from the womb through their third birthdays. The researchers have continued to track their development and are in the process of completing their fifth-year assessments. Braun expects to publish those findings in the next 18 months.

Ozonoff finds good reason to trust the results of this study. He was not affiliated with this research but is familiar with the work of the scientists collaborating on the study. “These are really good, experienced scientists who really know what they are doing and how to interpret the data.”

Ozonoff believes policymakers and regulators should not wait for additional research but should ban BPA now. He adds, “If it turns out it’s okay, we can always let it back in the environment.”