A pair of new studies using data from the same primate experiment suggest bisphenol A (BPA), a chemical used in certain plastics, thermal cash-register receipts, and canned foods, is causing serious bodily harm—even at very tiny doses such as those commonly detected in the human body.
BPA and Ticker Trouble
University of Idaho researchers made a strong case linking BPA to heart problems, becoming the first scientists to find cardiovascular effects in monkey fetuses whose mothers ingested BPA. This study, published in the journal PLOS One, is just the latest case suggesting BPA can travel from a pregnant mother into her unborn child. Emerging science is finding that when this chemical transfer occurs during critical windows of fetal development, it could lead to irreversible effects that may only show up in diseases that strike years or decades down the line.
"I would like people to understand that pregnant primate exposure to BPA alters expression of genes in the fetal heart, and that the genes that we observed changing suggest that this may be an unhealthy pattern," says study author Gordon K. Murdoch, PhD, associate professor of physiology in the University of Idaho's department of animal and veterinary science. "Studies such as these are essential towards understanding what may be occurring in humans."
This is one piece of associative evidence that suggests that BPA exposure induces changes in the fetal heart of a primate with similar metabolism and developmental processes as humans, Murdoch explains. We need more studies to see if these findings can be replicated, although other studies do indicate that BPA can interact with receptors for male and female hormones and thyroid hormones. "The developing primate heart utilizes all of these pathways in its normal development process," Murdoch points out.
Hundreds of rodent studies, and even dozens of human studies, show a link between BPA and all sorts of health problems. This primate study makes those findings even more real, since humans share very similar traits with the species.
"We can't do this experiment in humans," explains Frederick vom Saal, PhD, Curators' Professor of biological sciences at the University of Missouri-Columbia. "You can't ask pregnant women to be exposed to a chemical that could cause a diseased baby. That's off the table."
Widespread Bodily Damage
Professor vom Saal led another new BPA study using data from the same monkeys. The scientists fed pregnant animals BPA-laced fruit once a day for 50 days, bringing their bodily BPA levels to those commonly seen in humans. While BPA was only detectable in their babies' fetal blood for a brief, several-hour period, scientists observed some devastating changes in the babies—abnormalities in the fetal brains, lungs, mammary glands, uterus, and ovaries. These changes were not seen in unexposed monkey fetuses.
Since BPA is a hormone-disrupting chemical that acts like fake estrogen in the body, it's able to get into all of the developing organs, damaging the body's natural control system, potentially throwing off those systems forever, and leading to diseases like cancer, behavioral problems, and infertility—among other things—many scientists believe.
Being exposed to fake hormones as an adult can change your body, but it usually has the ability to bounce back, vom Saal explains. Just think about what happens when a woman takes a birth control pill. "It's altering what goes on, it's controlling your body," he says. But when she goes off of the pill, the reproductive system usually starts working again within a few months. When the fetus is exposed to BPA, it's different. The fetus doesn't have any protection. They don't have the detoxifying liver functions an adult has, he says.
"If you're a baby and your organ is developing—let's say your ovaries—and you're exposed to BPA, then all of the eggs in your ovary are going to be abnormal," vom Saal explains. "And they'll be that way for your entire life because all of the eggs that you'll ovulate are formed and processed through that initial phase of development when you were an embryo."
The cost of that, vom Saal says, will likely be lower fertility and a greater risk of producing abnormal babies. In essence, a pregnant mother's BPA exposure could go on to harm her future grandchild.
So why is this toxic chemical allowed in anything? For starters, manufacturing BPA is a $10-billion-a-year industry with powerful lobbyists, vom Saal says.
The other problem involves testing. The Food and Drug Administration (FDA) relies on last century's techniques for analyzing BPA damage, including things like removing and weighing ovaries and other organs, vom Saal says. He and other scientists have moved on to using very sensitive, 21st-century molecular tests.
In the old testing model, the one FDA recognizes, you have to poison an animal to see an effect that causes organs to shrink. Today, some nonindustry-funded university scientists are using more modern, cutting-edge techniques to study chemicals that mimic the control systems of the body. Scientists are looking at things like sensitive stages of development and chromosomes and gene expression—not weighing organs, something done 100 years ago—to ID damaging disruption. "They're revealing harm that's predictive of disease; you won't see that type of harm doing conventional weighing of organs and conventional cutting up of organs and looking at them in a microscope," he adds.
OK, now for the good news. There's a lot you can do to lower your levels of BPA. Here's what vom Saal recommends (he knows because he follows these practices and has bodily BPA levels much lower than the average American):
•Avoid canned food. Instead, opt for fresh or frozen.
•Avoid eating and drinking out of plastic, particularly #7 polycarbonate plastic.
•Don't heat plastics in the microwave—ever.
•Say no to cash-register receipt. Most are loaded with BPA that is readily absorbed through your skin and likely poorly metabolized.
For more reasons to get this toxic chemical out of your body, read 5 Weird Things BPA's Doing to Your Body.
Published on: February 25, 2014