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New Studies Show Harmful Effects of BPA on Pregnant Women


A new study advises pregnant women to avoid BPA-packaged products.

BPA is a potentially harmful chemical to pregnant women

BPA (Bisphenol-A) is a chemical used in almost every type of food packaging to extend shelf life, make the product more durable, and withstand extreme temperatures. But it’s also been linked to plenty of health concerns, the newest concerns for pregnant women in particular. In addition to the functionality of BPA, it is also linked to increase risks of cancer, heart disease, and reproductive abnormalities.

The Royal College of Obstetricians and Gynecologists (RCOG) released a paper this week advising pregnant women to avoid BPA when possible. “Pregnant women should reduce the use of foods and beverages in cans and plastic containers to minimize exposure to chemicals including BPA as part of a safety-first approach,” the RCOG said in statement.

The RCOG also said in the statement that fresh foods generally contain fewer, if any, non-food chemicals than processed and packaged foods.

Although it is not banned completely, the government has made small steps in banning BPA from drink packaging, like in baby bottles. Recently, Congressman Edward J. Markey of Massachusetts has taken action with the introduction of the Ban Poisonous Additives Act of 2013, which would prohibit any BPA in any food packaging or reusable food containers. BPA has also been linked to increase risks of cancer, heart disease, and reproductive abnormalities.

The EWG’s (Environmental Working Group) site has a “Guide to BPA”, which includes tips on how to avoid the products with the highest BPA levels. Tips included avoiding canned food, repurposing hard plastic containers, and saying no to receipts (40 percent-receipt paper is coated with BPA).


Consumer Alert: Toxic Hormone-Disrupting Chemical BPA is Leaching from Food Can Liners

As a new mother-and a scientist-I've watched with concern the glacial movement of state legislation seeking to ban toys and bottles that contain the hormone-disruptor bisphenol A. Bills first introduced in 2005 continue to plod through the state Assembly and Senate. Meanwhile, San Francisco, with a different view of risk, last year banned these types of toys and bottles from sale within city limits. While laudable, my own sense of urgency is not appeased because I've recently learned from the Organic Consumers Association that neither law addresses the biggest contributor of bisphenol A (BPA) in our bodies: canned foods.

A study by the Environmental Working Group tested commonly eaten canned foods from grocery stores in three US cities, including Oakland. Out of 97 cans, 57 percent contained detectable and often high levels of BPA. Pastas, soups, and infant formula accounted for some of the highest levels. The group estimates that BPA exposure is unsafe in 10 percent of all canned food and a staggering one-third of infant formula.

First synthesized in 1891, bisphenol A is an artificial estrogen that is particularly useful in creating plastic polymers. It is used in a wide variety of products manufactured around the globe, including CDs, fax paper, car parts, adhesives, and bullet-proof laminates. It creates hard plastics, like #7 water and baby bottles, and is also used in epoxy can liners to reduce spoilage of the food inside. BPA has been detected in rivers, soil, and household dust-and is turning up increasingly in studies of human chemical loads. One study found BPA in 95 percent of 400 American adults. It has also been detected in the amniotic fluid surrounding human babies.

For many years now, exposure to BPA has been associated with cancer, insulin resistance, and birth defects. Tests beginning in the '30s showed that high doses are toxic to rodents. In 1997, it was discovered that low levels of BPA produced harmful effects in male mice exposed in the womb, enlarging the prostate and lowering sperm count. What was most unexpected-and alarming-was that low-dose experiments produced worse effects in the mice than high-dose. Since then, nearly a hundred studies have shown BPA to be toxic in low doses on animals, producing such effects as insulin resistance, damaged DNA, miscarriage, decreased testosterone levels, early puberty, and the production of breast cancer and prostate cancer precursor cells.

Other tests suggest that some people, due to specific genetic makeup, may have a harder time ridding BPA from their bodies, which could make them more susceptible to BPA's toxic effects. These effects are most dangerous to pregnant women, babies, and young children. For example, in one Japanese study, women who had frequent miscarriages were found to have higher levels of BPA in their bloodstream than women who could carry pregnancies to term. In general, the hormone-unbalancing effects of BPA are not diagnosable as BPA exposure rather, they may show up as early onset of puberty, reduced fertility, type II diabetes, and an increased risk of cancer. The rise of cancer rates over the last few decades is correlated with the increased use of BPA in industry, although cause and effect is difficult to prove since BPA joins a long list of possible culprits.

While California legislators are at least wrestling with the issue, the Feds last reviewed BPA exposure in food in 1993, when the FDA tested some canned baby formulas and a few other canned foods. It estimated the level of BPA exposure in babies and adults and declared these levels safe, according to the high doses assumed to cause harm at the time. Then the low-dose studies started coming out in the late 1990s. In 1999, the FDA's George Pauli wrote in the Endocrine/Estrogen Letter that the FDA was unimpressed with these studies. In 2005, George Pauli sent a letter to a concerned California legislator saying there was "no reason [for the FDA] to change its long-held position that current [BPA] uses with food are safe." Therefore, the FDA does not measure or regulate the amount of BPA in food containers.

To decrease my family's own chemical load, I purchase organic foods, avoid plastics, buy wooden toys for my son, and use a fabric shower curtain rather than vinyl. But as a busy mom, I often resorted to easy recipes, many of which use canned foods.

After learning about the working group's study, I contacted nine companies that manufacture the canned foods my family uses. Only one, Trader Joe's, does not use epoxy liners containing BPA in its cans. All the others, including four makers of organic canned foods, said their can liners contain BPA. I was shocked to learn that the organic foods I was serving my family to keep toxins and pesticides out of our bodies contain BPA! A few of these companies sent me long explanations of why they use BPA in their linings, falling back on FDA guidelines as an indicator of BPA safety. Three claimed that there are no safe alternatives to using BPA liners to protect the canned food from spoiling.

"Not true," says Jovana Ruzicic of the testing group. "There are alternatives." I contacted eight companies-General Mills (including Muir Glen organics), B&G Foods, Campbell's, Amy's Kitchen, Natural Value, Early California Foods, Acirca (Walnut Acres organics), and Whole Foods 365 (including the company's organics)-to tell them I am no longer purchasing their products.

What can you do? Let's lobby the FDA to ban the use of bisphenol A in any food container, including metal can liners. At the very least, food containers containing BPA should be labeled as such. And support bills in the state legislature, such as California Assembly Bill 1108, that would ban bisphenol A and phthalates from toys and baby bottles. Ruzicic suggests that we push on the federal level for the reintroduction of the Kids Safe Chemical Act to protect children from BPA exposure from many sources.

And take the plunge: ask the manufacturers of the canned foods you eat if they use bisphenol A in their can liners. It's easy: their phone numbers and web page addresses are on the labels.

Here are a few other tips from Ruzicic:

¥ Choose fresh foods over canned.

¥ Do not use canned infant formula-or at least contact the manufacturer to see if bisphenol A is in the can liners.

¥ Avoid using #7 plastics and never microwave plastic containers or put them in the dishwasher. Throw out old, scratched plastic bottles and containers. Elephant Pharmacy carries a line of plastic baby bottles, Born Free, that do not contain BPA.

¥ Use stainless steel drinking bottles that do not have plastic liners, like those made by Real Wear and Kleen Kanteen.


Harvard study shows that harmful effects of BPA can be reversed with CoQ10 (coenzyme Q10)

A study performed at Harvard Medical School (HMS) in the United States by Maria Fernanda Hornos Carneiro and her research group shows that the harmful effects of BPA can be reversed by administering a supplement known as CoQ10 (coenzyme Q10), a substance naturally produced by the human body and found in beef and fish. Hornos Carneiro is a former São Paulo Research Foundation – FAPESP scholarship awardee.


Soy May Counter BPA Effects in Women Having IVF

WEDNESDAY, Jan. 27, 2016 (HealthDay News) -- A soy-rich diet may protect women undergoing infertility treatments from the harmful effects of a chemical widely used in food containers, a new study suggests.

Bisphenol A (BPA) -- which is found in such items as polycarbonate plastic water bottles and can linings -- can mimic estrogen, one of the two main sex hormones found in women, and the chemical has been linked to reproductive disorders.

More than 96 percent of Americans have BPA in their bodies, according to the U.S. Centers for Disease Control and Prevention.

This study included 239 women, aged 18 to 45, who underwent at least one in-vitro fertilization (IVF) cycle between 2007 and 2012. They completed questionnaires about their eating habits (176 consumed soy foods) and their urine was analyzed to measure BPA levels.

Among women who did not eat soy foods, those with higher BPA levels had lower rates of embryo implantation, fewer pregnancies that advanced to the point where the fetus could be seen on an ultrasound, and fewer live births than those with a soy-rich diet, the researchers found.

Continued

Among women who regularly consumed soy, BPA levels had no impact on IVF outcomes, according to the study, published Jan. 27 in the Journal of Clinical Endocrinology & Metabolism.

"Our study is the first to show a possible interaction between soy and BPA in humans," first author Dr. Jorge Chavarro, from Harvard School of Public Health and Brigham and Women's Hospital and Harvard Medical School, all in Boston, said in a journal news release.

"This is consistent with research in mice that found a soy-rich diet could protect against reproductive health problems associated with BPA exposure. More research is needed to determine why soy has this effect in humans," Chavarro added.

"Although it is recommended that women trying to get pregnant reduce their exposure to BPA, our findings suggest that diet may modify some of the risks of exposure to BPA, a chemical that is nearly impossible to completely avoid due to its widespread use," study senior author Dr. Russ Hauser, from Harvard School of Public Health, Massachusetts General Hospital and Harvard Medical School, said in the news release.

"Additional research could help identify other diet and lifestyle changes that may modify the effects of not only BPA exposure, but also exposure to other chemicals," Chavarro said.

Sources

SOURCE: Journal of Clinical Endocrinology & Metabolism, news release, Jan. 27, 2016


Highest reported BPA level in pregnant woman and associated abnormalities in infant

A new case study examining an infant's neurobehavioral abnormalities and extremely high bisphenol A (BPA) concentration of the baby's mother suggests a link between the two. The study, Environmental Health Perspectives: A Case Study of High Prenatal Bisphenol A Exposure and Infant Neonatal Neurobehavior, was led by researcher Sheela Sathyanarayana, MD of Seattle Children's Research Institute, and recently published online in Environmental Health Perspectives.

BPA, a synthetic, human-made chemical, is used in a wide variety of products including: can linings hard polycarbonate plastics such as baby bottles and reusable cups and dental sealants. Food may be the single largest source of BPA exposure due to contamination of foods during preparation and processing. BPA has estrogenic (hormone-like) properties. In animal studies, exposure to BPA early in life can lead to a variety of abnormalities in early development of the brain, behavior, prostate gland and breast tissues.

In human studies, exposure to BPA early in life has not been studied extensively. However, one study found an association between BPA exposure in pregnancy and abnormal acting out behaviors in female children. In adults, increased BPA exposure has been associated with changes in hormone concentrations, sperm quality, and endometriosis.

"Pregnant women are often exposed to BPA in their daily lives," said Sathyanarayana, pediatrician and environmental health specialist at Seattle Children's and assistant professor of pediatrics at the University of Washington School of Medicine. "It's important that they are aware of the potential sources of BPA, so they can take steps to avoid unnecessary exposures."

In this case study, Sathyanarayana and co-investigators reported on a specific mother/infant pair from a larger study (Health Outcomes and Measures of the Environment -- HOME study) that examined BPA exposures in pregnant women and then examined their infants for neurodevelopmental outcomes. At 27 weeks of pregnancy, the mother had the highest reported urinary BPA concentration of anyone in the general population. She reported consuming canned foods and beverages, and using and microwaving plastic food storage containers consistently during this pregnancy time period. All of these exposures could have led to her extremely high BPA concentration. Her infant had a normal newborn neurobehavioral exam but had many neurobehavioral abnormalities at the one-month study visit including: increased muscle tone, tremors, and abnormal movements. The child went on to have normal neurobehavioral assessments yearly from one to five years of age.

This case study confirms previous studies documenting multiple sources of BPA exposure in humans. Additionally, it highlights the need for medical providers to be aware of the harmful effects of BPA exposures so they may counsel families appropriately about prevention. The study also identifies potential sources of BPA exposure that can be targeted to reduce exposures in the future. "Families can decrease their exposure to BPA by eating fresh fruit and vegetables (as opposed to processed and canned foods) and by decreasing use of plastic food storage containers," said Sathyanarayana. "Check the recycling code of your plastics on the bottom. If it shows #7, then the plastic may contain BPA."

This research project was supported by grants from the National Institutes of Health and the National Institute of Environmental Health Sciences. Along with Sathyanarayana, the research team included: Joe M. Braun, PhD, from Harvard School of Public Heath Kimberly Yolton, PhD, and Bruce P. Lanphear, MD, from Cincinnati Children's Hospital Medical Center and Stacey Liddy, MS, from BC Children's Hospital.

Tips for reducing exposure of BPA for pregnant women and other parents and caregivers:

You may not be able to completely avoid BPA, but there are steps you can take to reduce your family's exposure to it:

  1. Limit the amount of canned foods your family eats.
  2. Rinse canned fruits and vegetables before eating. When possible, choose fresh fruits and vegetables instead.
  3. Limit the amount of canned beverages your family drinks.
  4. Avoid using plastic food and beverage storage containers with #7 on the bottom. If the recycling code is #7, then the plastic may contain BPA.
  5. Avoid using plastic baby bottles with #7 on the bottom.
  6. Decrease the use of all plastic food storage containers.
  7. Avoid using plastic food storage containers to heat food in the microwave. (High temperatures increase the chance of food absorbing BPA.)
  8. Use ceramic, glass, or other microwaveable dishes when heating food in the microwave.
  9. Avoid canned infant formula. Instead, use powdered formula or liquid formula sold in plastic or glass containers.

Story Source:

Materials provided by Seattle Children's. Note: Content may be edited for style and length.


Antioxidant reverses damage to fertility caused by exposure to bisphenol A

A study shows that administering coenzyme Q10 reverses damage done to germinative cells by BPA, a contaminant found in many kinds of plastic Credit: Maria Fernanda Hornos Carneiro & Nara Shin

Exposure to bisphenol A (BPA), an industrial chemical used to make certain plastics and resins, inner coatings for food cans and bottle tops, thermal paper used in store receipts, dental sealants and other products is a concern because of possible adverse health effects, including a reduction in fertility.

A study performed at Harvard Medical School (HMS) in the United States by Maria Fernanda Hornos Carneiro and her research group shows that the harmful effects of BPA can be reversed by administering a supplement known as CoQ10 (coenzyme Q10), a substance naturally produced by the human body and found in beef and fish. Hornos Carneiro is a former São Paulo Research Foundation—FAPESP scholarship awardee.

The article published in the journal Genetics is the first to present this strategy for reversing the effects of BPA in the organism. In this study, the researchers tested the antioxidant action of CoQ10 in nematodes of the species Caenorhabditis elegans exposed to BPA.

As an excellent antioxidant, CoQ10 is an electron donor. By donating its electrons, it stabilizes free radicals, reducing the oxidative stress and cell damage caused by BPA.

"BPA has oxidation potential as it's chemically unstable and produces reactive oxygen and nitrogen species. When the antioxidant reserves in cells [electron donors] run out, the amount of reactive oxygen and nitrogen increases. Because of their chemical instability, they 'poach' electrons from mitochondria and other cellular organelles, cell membranes, proteins, and even DNA, damaging cells significantly and potentially causing cell death. If this problem becomes extensive, it poses a major threat to the organism," Hornos Carneiro told.

The study measured the number of fertilized eggs laid and hatched and the number of progeny that reached adulthood. The problems detected can be compared to difficulty in becoming pregnant, miscarriages and chromosome anomalies in humans.

"BPA is a chemical contaminant that acts as an endocrine disruptor, causing cellular oxidative stress [an imbalance between oxidant and antioxidant molecules], which results in damage to gametes and embryos," said Hornos Carneiro, who conducted the study under the supervision of HMS Professor Monica Paola Colaiácovo. "In the study, the worms exposed to BPA and given CoQ10 displayed lower egg cell death rates, less DNA breakage and fewer abnormalities in chromosomes during cell division, as well as less cellular oxidative stress."

In the experiment, worms were exposed to different combinations of BPA, CoQ10 and a solvent (DMSO): solvent only, solvent and CoQ10, BPA only, and BPA plus CoQ10.

The amount of exposure to BPA mimicked the estimated amount in humans. "We know it's practically impossible to avoid exposure to BPA and similar contaminants in this day and age, so we looked for a strategy to minimize the harm done. Many studies have shown that age reduces fertility in women, and because exposure to BPA [and other endocrine disruptors] occurs throughout life, it's not yet possible to estimate separately the extent to which observed infertility is due to exposure to toxic chemicals in the external environment and how much is due to aging," Hornos Carneiro said.

The nematodes used in the study were transgenic, with a fluorescent protein sequence inserted into their DNA to enable in vivo observation of protein expression. Fluorescent antibodies were also used, as well as advanced microscopy and molecular biology techniques. The researchers were thereby able to observe in real time the effects produced at the cellular and molecular levels during the process of cell division (meiosis) and embryo formation in the worms.

According to Hornos Carneiro, BPA's chemical structure is similar to that of estrogen, a female sex hormone that plays a key role in ovulation. As a result, BPA can bind to estrogen receptors in humans, leading to a number of significant effects. "Depending on the tissue, the effects may be pro-estrogenic or anti-estrogenic, with an impact not just on the reproductive system but also on other systems and processes that are important to a person's health," she said.

Hornos Carneiro is currently a professor in the School of Chemistry and Pharmacy at the Pontifical Catholic University of Chile. She conducted the study at the University of São Paulo's Ribeirão Preto School of Pharmaceutical Sciences (FCFRP-USP) in Brazil with the support of a FAPESP scholarship for postdoctoral research internship abroad.

DNA breakage and mitochondrial dysfunction

According to Hornos Carneiro, exposure of the worms to BPA alone resulted in more DNA breaks. "This was potentially due to the action of reactive oxygen species formed as a result of the presence of the contaminant in the organism," she said. "We found that the breaks were not correctly repaired in this group of worms."

The damage was observed by monitoring a protein involved in DNA breakage and repair when genetic material is exchanged between homologous chromosomes during meiosis.

This exchange of genetic material, known as crossing over, is important for increasing genetic diversity and driving evolution. "One hypothesis is that the increase in DNA breakage [and inefficient repair] was due to a rise in gonad oxidative stress caused by BPA," she said.

Another finding was that mitochondrial dysfunction increased. Mitochondria are energy-producing organelles in cells. "Because of oxidative stress, mitochondrial membrane potential was significantly altered in the worms exposed only to BPA, while in the group that received the CoQ10 supplement, this marker was much improved," Hornos Carneiro said.

The effect of BPA on embryos was also studied in this experiment. As a hermaphrodite, C. elegans self-fertilizes, and it is therefore possible to observe in its gonads all stages of germinative cell development in meiosis up to the polar corpuscle and embryo formation.

"In the study, we observed embryo formation in vivo using a technique called live imaging," Hornos Carneiro explained. "The benchmark for analysis of the occurrence of defects was the first cell division [the precise moment at which the unicellular embryo divides in two]. In the group exposed only to BPA, a larger number of defects were observed, such as formation of chromatin bridges and cell division cessation."


Pregnant Women Beware! Ditch These 2 Foods From Your Diet For Health Of Your Baby

Pregnant women are advised to be very careful about their diet. Certain foods are said to be a strict no for expectant mothers and nutritionists and health experts always advise pregnant women to omit these foods and drinks from their diets, lest their harm their babies in some way. This is why during pregnancy a healthy meal plan should ideally be in place to ensure health of the mother and the baby. A new study has pointed towards the harmful effects of consuming potato chips and vegetable oil during pregnancy. The study warns mothers about the side-effects of consuming too much of these two foods, saying that such a diet may increase risk of complications during pregnancy and may even hamper development of the baby. However, it's the reason behind this warning that's a shocker- omega 6 fatty acids.

Researchers have said excessive presence of omega 6 fats, particularly linoleic acid, in pregnancy diet may result in increased inflammation and in the mother's body and may even increase the risk of heart diseases. The results of the study were published in The Journal of Physiology and they said that consuming linoleic acid that equaled three times the safe consumption limit, was harmful for mothers during pregnancy term. The study was conducted on rats and it was observed that pregnant rodents who consumed diets rich in linoleic acid had high concentrations of inflammatory proteins in their livers.

Additionally, they also had high concentrations of a protein which could induce contractions in the uterus during pregnancy, as well as low levels of a hormone which is important for regulating growth and development of the baby. Human diets rich in linoleic acid, also tend to be rich in fats, sugar and salt, said the researchers. Study lead author Deanne Skelly, Professor at Griffith University in Australia said in an IANS report, "It is important for pregnant women to consider their diet, and our research is yet another example that potentially consuming too much of a certain type of nutrient can have a negative impact on the growing baby."

(This content including advice provides generic information only. It is in no way a substitute for qualified medical opinion. Always consult a specialist or your own doctor for more information. NDTV does not claim responsibility for this information.)


Study finds highest reported BPA level in pregnant woman and associated abnormalities in infant

A new case study examining an infant's neurobehavioral abnormalities and extremely high bisphenol A (BPA) concentration of the baby's mother suggests a link between the two. The study, Environmental Health Perspectives: A Case Study of High Prenatal Bisphenol A Exposure and Infant Neonatal Neurobehavior, was led by researcher Sheela Sathyanarayana, MD of Seattle Children's Research Institute, and recently published online in Environmental Health Perspectives.

BPA, a synthetic, man-made chemical, is used in a wide variety of products including: can linings hard polycarbonate plastics such as baby bottles and reusable cups and dental sealants. Food may be the single largest source of BPA exposure due to contamination of foods during preparation and processing. BPA has estrogenic (hormone-like) properties. In animal studies, exposure to BPA early in life can lead to a variety of abnormalities in early development of the brain, behavior, prostate gland and breast tissues.

In human studies, exposure to BPA early in life has not been studied extensively. However, one study found an association between BPA exposure in pregnancy and abnormal acting out behaviors in female children. In adults, increased BPA exposure has been associated with changes in hormone concentrations, sperm quality, and endometriosis.

"Pregnant women are often exposed to BPA in their daily lives," said Sathyanarayana, pediatrician and environmental health specialist at Seattle Children's and assistant professor of pediatrics at the University of Washington School of Medicine. "It's important that they are aware of the potential sources of BPA, so they can take steps to avoid unnecessary exposures."

In this case study, Sathyanarayana and co-investigators reported on a specific mother/infant pair from a larger study (Health Outcomes and Measures of the Environment - HOME study) that examined BPA exposures in pregnant women and then examined their infants for neurodevelopmental outcomes. At 27 weeks of pregnancy, the mother had the highest reported urinary BPA concentration of anyone in the general population. She reported consuming canned foods and beverages, and using and microwaving plastic food storage containers consistently during this pregnancy time period. All of these exposures could have led to her extremely high BPA concentration. Her infant had a normal newborn neurobehavioral exam but had many neurobehavioral abnormalities at the one-month study visit including: increased muscle tone, tremors, and abnormal movements. The child went on to have normal neurobehavioral assessments yearly from one to five years of age.

This case study confirms previous studies documenting multiple sources of BPA exposure in humans. Additionally, it highlights the need for medical providers to be aware of the harmful effects of BPA exposures so they may counsel families appropriately about prevention. The study also identifies potential sources of BPA exposure that can be targeted to reduce exposures in the future. "Families can decrease their exposure to BPA by eating fresh fruit and vegetables (as opposed to processed and canned foods) and by decreasing use of plastic food storage containers," said Sathyanarayana. "Check the recycling code of your plastics on the bottom. If it shows #7, then the plastic may contain BPA."

This research project was supported by grants from the National Institutes of Health and the National Institute of Environmental Health Sciences. Along with Sathyanarayana, the research team included: Joe M. Braun, PhD, from Harvard School of Public Heath Kimberly Yolton, PhD, and Bruce P. Lanphear, MD, from Cincinnati Children's Hospital Medical Center and Stacey Liddy, MS, from BC Children's Hospital.

Tips for reducing exposure of BPA for pregnant women and other parents and caregivers:


What BPA Does to the Body

Some two decades ago, Hunt and her colleagues stumbled onto a BPA breakthrough while working on another project. The scientists were using lab mice to model how even subtle hormonal changes can impact a woman’s ability to develop a healthy egg. Initially, their experiment appeared to be working well, returning results on par with what they’d expected.

Then their results went haywire. “We went from normal control data one week to completely abnormal data the next,” Hunt says.

Eventually, they tracked down the culprit: The janitorial staff had used a harsh cleaner on all the plastic mice cages. That damaged the plastic, allowing it to leach into the mice.

Since the 1970s, scientists had been finding troubling hints that BPA had negative health effects. But Hunt’s research and subsequent work provided damning evidence that mice — and their babies — that were exposed to BPA had abnormal chromosomes.

Initially, scientists thought BPA was acting like a form of weak estrogen, the primary female sex hormone that regulates reproduction and some sexual characteristics. (Men also have estrogen, but at lower levels.) Researchers believed BPA was binding to or disrupting the same receptors used by estrogen. And it does seem like that’s often what’s happening.

However, Hunt says it’s also now clear that the reality is far more complicated. BPA doesn’t just interfere with estrogen receptors it can also interfere with thyroid hormone receptors and androgen receptors. Androgen includes testosterone, the primary male sex hormone. (Women have testosterone, too).

Since BPA has different effects in different places in the body at different times, that makes it very hard to study. For instance, rather than being able to nail down how BPA and its alternatives behave in the ovary, researchers have only been able to specify how it acts in the ovary at specific times.

“It’s really complicated, and I think there’s a lot of interaction we don’t completely understand,” says Hunt. “The way that it induces its effects is variable. It’s actually quite interesting. It’s like a little chameleon of a chemical.”

These complexities have allowed lingering doubts about how conclusive the science is that BPA can harm humans, not just animals. Historically, industry research has claimed the chemical is safe to use even the federal government recognizes BPA as safe at certain levels.

But researchers have found evidence of abnormalities in the eggs of mice given less than half the amount of BPA that the Environmental Protection Agency has declared safe. And scientists have now studied a huge range of health complications that have shown links to BPA exposure . The list is staggering:

Impaired thyroid function

Increased risk of obesity

Increased risk of high blood pressure

Increased erectile difficulty

Childhood behavioral issues


Study finds highest reported BPA level in pregnant woman and associated abnormalities in infant

SEATTLE, May 11, 2011 -- A new case study examining an infant's neurobehavioral abnormalities and extremely high bisphenol A (BPA) concentration of the baby's mother suggests a link between the two. The study, Environmental Health Perspectives: A Case Study of High Prenatal Bisphenol A Exposure and Infant Neonatal Neurobehavior, was led by researcher Sheela Sathyanarayana, MD of Seattle Children's Research Institute, and recently published online in Environmental Health Perspectives.

BPA, a synthetic, man-made chemical, is used in a wide variety of products including: can linings hard polycarbonate plastics such as baby bottles and reusable cups and dental sealants. Food may be the single largest source of BPA exposure due to contamination of foods during preparation and processing. BPA has estrogenic (hormone-like) properties. In animal studies, exposure to BPA early in life can lead to a variety of abnormalities in early development of the brain, behavior, prostate gland and breast tissues.

In human studies, exposure to BPA early in life has not been studied extensively. However, one study found an association between BPA exposure in pregnancy and abnormal acting out behaviors in female children. In adults, increased BPA exposure has been associated with changes in hormone concentrations, sperm quality, and endometriosis.

"Pregnant women are often exposed to BPA in their daily lives," said Sathyanarayana, pediatrician and environmental health specialist at Seattle Children's and assistant professor of pediatrics at the University of Washington School of Medicine. "It's important that they are aware of the potential sources of BPA, so they can take steps to avoid unnecessary exposures."

In this case study, Sathyanarayana and co-investigators reported on a specific mother/infant pair from a larger study (Health Outcomes and Measures of the Environment - HOME study) that examined BPA exposures in pregnant women and then examined their infants for neurodevelopmental outcomes. At 27 weeks of pregnancy, the mother had the highest reported urinary BPA concentration of anyone in the general population. She reported consuming canned foods and beverages, and using and microwaving plastic food storage containers consistently during this pregnancy time period. All of these exposures could have led to her extremely high BPA concentration. Her infant had a normal newborn neurobehavioral exam but had many neurobehavioral abnormalities at the one-month study visit including: increased muscle tone, tremors, and abnormal movements. The child went on to have normal neurobehavioral assessments yearly from one to five years of age.

This case study confirms previous studies documenting multiple sources of BPA exposure in humans. Additionally, it highlights the need for medical providers to be aware of the harmful effects of BPA exposures so they may counsel families appropriately about prevention. The study also identifies potential sources of BPA exposure that can be targeted to reduce exposures in the future. "Families can decrease their exposure to BPA by eating fresh fruit and vegetables (as opposed to processed and canned foods) and by decreasing use of plastic food storage containers," said Sathyanarayana. "Check the recycling code of your plastics on the bottom. If it shows #7, then the plastic may contain BPA."

This research project was supported by grants from the National Institutes of Health and the National Institute of Environmental Health Sciences. Along with Sathyanarayana, the research team included: Joe M. Braun, PhD, from Harvard School of Public Heath Kimberly Yolton, PhD, and Bruce P. Lanphear, MD, from Cincinnati Children's Hospital Medical Center and Stacey Liddy, MS, from BC Children's Hospital.

Tips for reducing exposure of BPA for pregnant women and other parents and caregivers:

You may not be able to completely avoid BPA, but there are steps you can take to reduce your family's exposure to it:

    Limit the amount of canned foods your family eats.

For more information for parents and caregivers, visit:

Department of Health and Human Services
http://www. hhs. gov/ safety/ bpa/
Bisphenol A (BPA) Information for Parents

For more information for physicians, visit:

Pediatric Environmental Health Specialty Units
http://www. aoec. org/ PEHSU. htm
Made up of professionally trained environmental health experts including physicians. Provides evidence based education and consultations to health care providers, state and local governments, and individual families.

American Academy of Pediatrics: Pediatric Environmental Health Handbook
https://www.nfaap.org/netforum/eweb/dynamicpage.aspx?site=nf.aap.org&webcode =aapbks_productdetail&key=17837ee5-f0fd-4486-9bcc-64f986b0f703
Provides description and clinical guidelines for addressing common pediatric environmental health topics.

National Environmental Education Foundation
http://www. neefusa. org/ health/ PEHI/ index. htm
Provides numerous resources on environmental education including handouts on taking a pediatric environmental health history.

Physicians for Social Responsibility
http://www. psr. org/ resources/ pediatrictoolkit. html#what
Provides evidence based environmental health toolkits for health care providers to use. Can get CME credit for taking the toolkit course

About Seattle Children's Research Institute

At the forefront of pediatric medical research, Seattle Children's Research Institute is setting new standards in pediatric care and finding new cures for childhood diseases. Internationally recognized scientists and physicians at the Research Institute are advancing new discoveries in cancer, genetics, immunology, pathology, infectious disease, injury prevention, and bioethics. With Seattle Children's Hospital and Seattle Children's Hospital Foundation, the Research Institute brings together the best minds in pediatric research to provide patients with the best care possible. Children's serves as the primary teaching, clinical, and research site for the Department of Pediatrics at the University of Washington School of Medicine, which consistently ranks as one of the best pediatric departments in the country. For more information, visit http://www. seattlechildrens. org/ research.

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