Breast Milk Exposing Infants to BPA

Researchers have confirmed that a majority of infants are now being exposed to Bisphenol A (BPA) – a well-known endocrine disruptor – through their breast milk.

Hundreds of moms and babies studied

The researchers, from the Republic of Korea’s Sookmyung Women’s University College of Pharmacy, tested 325 mothers and infants. They were from mostly middle class families in the Republic of Korea (South Korea) who were born within two weeks of the study. The researchers sampled the mothers’ breast milk and tested the presence of BPA in the colostrum. The researchers also tested the presence of two other endocrine disrupting phenols in the breast milks.

Together with this testing, the researchers studied the health of the mothers and their babies as well as the mothers’ diets.

The researchers found total and conjugated BPA within the breast milk in over 70% of the women. They also found free BPA within the breast milk of nearly 40% of the women.

The researchers also found other phenols in the mothers’ breast milk. These included 4-nonylphenol and 4-tertiary-octylphenol, which were found in 16% and 27% of the mothers’ breast milk, respectively.

Using total BPA as a gradient, the researchers established that the infants were consuming approximately 1.20 parts per billion of BPA per day with every 500 milliliters of breast milk they were drinking.

This study confirms another study done last winter by researchers from the Simmons College School of Nursing and Health Sciences. Here the researchers tested 27 mothers and their newly born children. This study found that 75% of the mothers’ breast milks had significant levels of total BPA. Here the levels within breast milk ranged from .4 to 1.4 parts per billion.

Almost all the babies had significant BPA

Furthermore, this study from Simmons College found that 93% of the infants – aged between three and 15 months – had significant levels of BPA in their urine.

The Korean researchers also found that among those children with congenital birth defects, the mother’s breast milk had significantly higher levels of BPA and the two phenols tested.

The research also found that mothers who had toxemia or related health disorders had higher levels of 4-nonylphenol in their breast milk.

While the South Korean researchers utilized a level of 50 parts per billion as dangerous to a baby’s health, research has yet to clearly establish the long term effects of consistent exposure to BPA during infancy and childhood. On this subject the researchers commented:

“Particularly, considering low-body weights and susceptibility, we suspect that body burden or real exposure level of infants or children to BPA or APs is expected to be heavier than those of adults.”

The Korean researchers also established that the primary sources for higher BPA levels in the mothers’ breast milks included eating dairy products and using BPA-containing detergents. Notable associations not found between breast milk BPA included pollution and the use of plastic wrap.

Nursing school researchers have found the breastmilk of most women and the urine samples of most babies contain the hormone disruptor bisphenol A (BPA).

Breast milk and babies tested for BPA

The research comes from the School of Nursing and Health Sciences at Boston’s Simmons College. The researchers tested the breast milk of 27 women and the urine of 31 infants. The infants were between three months and 15 months old, and they were screened for environmental exposure to BPA sources. The infants tested had no known environmental exposure outside of a typical household.

The tests analyzed the levels of unconjugated or free BPA as well as total BPA levels – including conjugated BPA. The researchers used solid-phase extraction along with liquid chromatography-isotope dilution with mass spectrometry to determine the levels with accuracy.

The testing found that 93% of the children had significant total BPA levels – averaging from 1.2 to 4.4 micrograms per liter.

The testing also found that 75% of the mothers’ breast milk had detectible amounts of total BPA – in the range of 0.4 to 1.4 micrograms per liter.

The researchers found that levels of free BPA – considered more harmful – were lower than total BPA levels.

The researchers checked the feeding habits of the children to determine whether there was a relationship between their diet and their BPA levels, but found no relationship. Surprisingly, they also could not find a significant relationship between the amount of BPA in the mother’s breast milk and the BPA levels of her baby’s urine.

Adult population tested for BPA

Research from the German Institute for Prevention and Occupational Medicine confirmed similar results from urine and plasma samples taken among the German population between 1995 and 2009. Analyzing 600 urine and plasma samples, the researchers found that total BPA was detectible in over 96% of the samples tested. The BPA concentrations averaged 1.49 micrograms per liter and high levels (in the 95th percentile) averaged 7.37 micrograms per liter.

The researchers found that unconjugated BPA made up the bulk of the BPA found. This indicates environmental exposure. The researchers also concluded, “total BPA in urine as the most appropriate and robust marker for BPA exposure assessment.”

The researchers did not find a significant increase or decrease in overall BPA levels between 1995 and 2009 among the samples.

This of course confirms what science has discovered among so many marine mammals and fish – that BPA tends to bioaccumulate gradually within the tissues and migrates up the food chain. And marine researchers are finding increasing BPA levels among sealife as microplastics are accumulating in the oceans.

These studies also confirm research done in October by the U.S. Centers for Disease Control and Prevention that showed children between three and eleven years of age are accumulating BPA and seven other toxins.

In another study, Swedish researchers tested BPA levels among 100 women and correlated those levels with their exposure to BPA from their diets. They found that the most prevalent BPA sources were from fish, meat, potatoes, and dairy products. This study also indicated the women’s primary source of exposure is through the diet, a direct result of animals bioaccumulating BPA and this accumulation effect finding its way up the food chain to humans. In this study, 76% of the women had detectible levels of BPA in their blood.

BPA disrupts hormones

Bisphenol A is a known hormone disruptor, as it attaches to estrogen receptors within the body. It also has been linked with cancer. Though some government agencies still question the health risks of BPA, in 2006 the Chemical Heritage Foundation, upon request by Congress, conducted a review of BPA research to date. The research concluded that BPA levels found in humans are enough to cause harm and metabolism changes within many of the body’s tissues and organs. “New research on very-low-dose exposure to BPA suggests an association with adverse health effects, including breast and prostate cancer, obesity, neurobehavioral problems, and reproductive abnormalities,” it was concluded. Studies since have confirmed this position.

BPA is a plasticizer and monomer, so most plastics contain BPA. BPA is also used ubiquitously as a building material and among epoxy applications. Industrial manufacturers utilize BPA in many processes, leading to its discharge into the environment. Plastics and microplastics leach into our waterways and soils through garbage and waste disposal plants.

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