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Even though many, many personal care products contain parabens, the evidence is accumulating that parabens have negative health effects. And now research suggesting that perhaps they may be a factor in developing breast cancer. This latest study was done "in vitro" - meaning looking at the effects of chemicals on human breast cells (in culture dishes), but the results absolutely should make someone think twice about all the parabens in products, and how they accumulate in us. Research has already found parabens in the human breast, but many thought that the levels were too low to promote cancer.

Parabens are common ingredients in cosmetics, shampoos, body lotions and sunscreens, where they are used to prevent microbial growth and prolong shelf life.  Common names of parabens are: methylparaben, ethylparaben, propylparaben, and butylparaben. Detectable levels of multiple parabens are present in human urine and breast tissue. Bottom line: Parabens are endocrine disrupting chemicals that mimic estrogens and may have effects at very low doses to stimulate breast cancer cell growth. So read labels of personal care products and avoid those with parabens. From Futurity:

New Tests Suggest Parabens Carry Cancer Risk

A group of chemicals called parabens—common ingredients in personal care products—may interact with growth factors in the body to increase the risk of breast cancer, according to new research. Parabens are preservatives widely used in everything from shampoos and cosmetics to body lotions and sunscreens. The chemicals have generated increasing health concerns, however, because they mimic estrogens, which have been linked to an increased risk of breast cancer and reproductive problems.

“Although parabens are known to mimic the growth effects of estrogens on breast cancer cells, some consider their effect too weak to cause harm,” says lead investigator Dale Leitman, a gynecologist and molecular biologist at the University of California, Berkeley, and an adjunct associate professor of nutritional sciences and toxicology. “But this might not be true when parabens are combined with other agents that regulate cell growth.”

Existing chemical safety tests, which measure the effects of chemicals on human cells, look only at parabens in isolation, he says. They fail to take into account that parabens could interact with other types of signaling molecules in the cells to increase breast cancer risk.

To better reflect what goes on in real life, Leitman and his colleagues looked at breast cancer cells expressing two types of receptors: estrogen receptors and HER2. Approximately 25 percent of breast cancers produce an abundance of HER2, or human epidermal growth factor receptor 2. HER2-positive tumors tend to grow and spread more aggressively than other types of breast cancer.

The researchers activated the HER2 receptors in breast cancer cells with a growth factor called heregulin that is naturally made in breast cells, while exposing the cells to parabens. Not only did the parabens trigger the estrogen receptors by turning on genes that caused the cells to proliferate, but also the effect was significant. The parabens in the HER2-activated cells were able to stimulate breast cancer cell growth at concentrations 100 times lower than in cells that were deprived of heregulin.

The study demonstrates that parabens may be more potent at lower doses than previous studies have suggested, which may spur scientists and regulators to rethink the potential impacts of parabens on the development of breast cancer, particularly on HER2 and estrogen receptor positive breast cells. The findings also raise questions about current safety testing methods that may not predict the true potency of parabens and their effects on human health.

Beware of nail polish because it may be contaminating your body with an endocrine disrupting chemical.  A study co-authored by researchers at Duke University and Environmental Working Group (EWG) detected evidence of a common nail polish chemical called triphenyl phosphate, or TPHP, in the bodies of every woman who volunteered to paint her nails for the study.There is growing evidence suggesting that TPHP may affect hormone regulation, metabolism, reproduction and development. Unfortunately, even if it is not listed on the label, it may still be in the product. It is also used as a fire retardant (and the evidence from studies says to avoid fire retardants). Go to the EWG site for more on nail polish brands.From Environmental Working Group (EWG):

Duke-EWG Study Finds Toxic Nail Polish Chemical In Women’s Bodies

Researchers at Duke University and Environmental Working Group have found evidence of a suspected endocrine-disrupting chemical widely used in popular nail polishes in the bodies of more than two-dozen women who participated in a biomonitoring study. The study, published today in Environment International, found that all women had a metabolite of triphenyl phosphate, or TPHP, in their bodies just 10 to 14 hours after painting their nails. Their levels of diphenyl phosphate or DPHP, which forms when the body metabolizes TPHP, had increased by nearly sevenfold.

According to EWG’s Skin Deep® cosmetics database, more than 1,500 nail products including polishes made by Sally Hansen, OPI and Wet N Wild, contain TPHP. Click here for a list of brands that list TPHP as an ingredient. More nail polishes may contain undisclosed TPHP.  The Duke-EWG study tested 10 polishes for TPHP and found the chemical in eight of them. Two of the eight with TPHP did not list the ingredient on their labels.  ...continue reading "Secret Hazard of Nail Polish"

 More and more studies are finding negative health effects from hormone disrupting chemicals (which we are exposed to every single day, and subsequently which are in all of us), such as parabens, phthalates, Bisphenol-A (BPA), and chemical substitutes for BPA such as Bisphenol-S (BPS) and BPF.  The last post had some recent studies that looked at health effects of hormone disrupting chemicals. The following article points out some of the many difficulties in developing packaging that is safe and doesn't leach endocrine disrupting chemicals or even other chemicals.

We generally focus on hormone disrupting chemicals in plastic bottles or metal cans (which their epoxy liners), but other parts of packaging may (or may not) also leach chemicals. Some leaching may occur with the adhesives used to seal foil pouches, and the polypropylene inner layers also may leach stabilizers. Glass jars are OK, but jar lids may be equipped with BPA-based epoxy liners and/or gaskets that leach plasticizers. Greaseproof wrappers may leach poly- and perfluorinated compounds used to make some packaging greaseproof (may occur if packaging is from India and China - because it is legal to import into USA and use).  Some ceramic kitchenware - the glazes used in artisanal pottery and older mass produced ceramics may leach toxic metals, especially lead. There can even be "offset migration" which occurs when the printed outer surface of food packaging transfers chemicals to the inner food-contact surface.  Whew...

Bottom line: Even BPA alternatives (labeled BPA-free) should be viewed as the same as BPA (as endocrine disruptors) - in other words, currently there are no good BPA substitutes. Read labels and try to minimize plastics in personal care products (e.g., lotion, fragrances) and your food if possible (e.g., choose glass, stainless steel, wax paper, aluminum foil). This is especially important during pregnancy.  Don't microwave food in a plastic dish or container, or covered with plastic wrap. Eat fresh foods and try to avoid soda cans and other packaged, processed foods, especially in plastic containers or metal cans. From Environmental Health Perspectives: A Hard Nut to Crack: Reducing Chemical Migration in Food-Contact Materials

When we buy food, we’re often buying packaging, too. From cherries to Cheez-It® crackers, modern foods are processed, transported, stored, and sold in specialized materials that account, on average, for half the cost of the item, according to Joseph Hotchkiss, a professor in Michigan State University’s School of Packaging. Consumer-level food packaging serves a wide range of functions, such as providing product information, preventing spoilage, and protecting food during the journey from production to retail to pantry, fridge, or freezer. That’s why food producers lavish so much time and money on it.

But what happens when these valuable and painstakingly engineered containers leach chemicals and other compounds into the food and drink they’re designed to protect? Such contamination is nearly ubiquitous; it happens every day, everywhere packaged food is found, with all common types of packaging, including glass, metal, paper, and plastic. Even as awareness of the issue grows, large-scale solutions that are scientifically and financially viable remain out of reach. The challenges in reaching them are many.  ...continue reading "Chemicals Migrate From Containers to Food"

More and more studies are finding negative health effects from hormone disrupting chemicals (which we are exposed to every single day, and subsequently which are in all of us), such as parabens, phthalates, Bisphenol-A (BPA), and chemical substitutes for BPA such as Bisphenol-S (BPS) and BPF. The following are a few recent studies and one article from my files. Also check out the other endocrine disrupting chemical studies I've posted (SEARCH: 'endocrine disruptors', and 'phthalates').

Bottom line: Read labels and try to minimize plastics in personal care products (e.g., lotion) and your food if possible (e.g., choose glass, stainless steel, wax paper, aluminum foil). This is especially important during pregnancy.  Even BPA alternatives (labeled BPA-free) should be viewed as the same as BPA - as endocrine disruptors. In other words, currently there are no good BPA substitutes. Don't microwave food in a plastic dish or container, or covered with plastic wrap. Eat fresh foods rather than packaged, processed foods. From Newsweek:

BPA Is Fine, If You Ignore Most Studies About It

Bisphenol-A (BPA) is either a harmless chemical that’s great for making plastic or one of modern society’s more dangerous problems. Depends whom you ask. BPA is in many types of plastics and the epoxy resins that line most aluminum cans, as well as thermal papers like receipts. It is an endocrine disruptor that mimics estrogen, a hormone especially important in sexual development, and the fact that it’s all over the place worries many people. Newsweek spoke with about 20 scientists, leaders in the field of BPA research, and the majority say it is likely (though not certain) that the chemical plays a role in a litany of health concerns: obesity, diabetes, problems with fertility and reproductive organs, susceptibility to various cancers and cognitive/behavioral deficits like ADHD ...continue reading "More Negative News About Hormone Disrupting Chemicals"

A report released this week by the Endocrine Society states that the list of health problems that scientists can confidently link to exposure to hormone-disrupting chemicals has grown to include: diabetes, cardiovascular disease, obesity, reproductive and developmental problems, thyroid impairment, certain reproductive cancers, and neurodevelopmental problems such as decreased IQ. This statement (report) is based on the summaries of 1300 studies on endocrine disrupting chemicals (EDCs), and it also adds support to the idea that even minute doses of these chemicals can interfere with the activity of natural hormones, which play a major role in regulating physiology and behavior. The statement also stated that most industrial chemicals released into the environment—numbering in the tens of thousands—have never been tested for endocrine-disrupting potential. EDCs include such common chemicals as bisphenol A (BPA), phthalates, parabens, some pesticides (e.g., atrazine), flame retardants, some persistent organic pollutants, and dioxins.

Where are endocrine disruptors found? People are exposed to chemicals with estrogenic effects in their everyday life, because endocrine disrupting chemicals are found in low doses in thousands of products. Many plastic products, including those advertised as "BPA free", have been found to leach endocrine-disrupting chemicals (the substitute chemicals are no better than BPA, and may be worse). Examples: plastic food containers which then leach into foods, linings of metal beverage, formula, and food cans, soft plastic toys, dental sealants, consumer goods, receipts, personal care products that contain parabens or phthalates (e.g., found in lotions,sunscreens, fragrances), household products (such as cleaning products, vinyl shower curtains) , cars (that new car smell in car interiors), etc. Americans love plastics, but there is a serious human health cost.

NOTE: To minimize EDC exposure - try to avoid plastic food and beverage containers. Instead try to use glass, stainless steel, or ceramics. Eat as many unprocessed and fresh foods as possible. Use cloth shower curtains. Read labels and avoid BPA, phthalates, parabens. Avoid fragrances. Don't use or buy non-stick pans, stain and water-resistant coatings on clothing, furniture and carpets. When buying new furniture, check that it doesn't have added fire retardants.

Of course any public discussion of the harms from endocrine disrupting chemicals, as well as the newly released Endocrine Society report, is drawing sharp criticisms from the chemical industry (especially the American Chemistry Council, the largest trade group for the chemicals industry). Of course. We all know that the lobbying efforts by the chemical industry to suppress and deny the evidence of harm to humans from EDCs has been and will continue to be massive. Sadly, but at this point EDCs are found in almost everyone on earth. More about the report, from Science Daily:

Chemical exposure linked to rising diabetes, obesity risk

Emerging evidence ties endocrine-disrupting chemical (EDC) exposure to two of the biggest public health threats facing society -- diabetes and obesity. EDCs contribute to health problems by mimicking, blocking or otherwise interfering with the body's natural hormones. By hijacking the body's chemical messengers, EDCs can alter the way cells develop and grow. Known EDCs include bisphenol A (BPA) found in food can linings and cash register receipts, phthalates found in plastics and cosmetics, flame retardants and pesticides. The chemicals are so common that nearly every person on Earth has been exposed to one or more.  ...continue reading "New Report About Harms of Endocrine Disruptors"

A recent report found that when a person is exposed to a little bit (or low doses) of a lot of different commonly encountered chemicals, than the combinations over time may cause changes that increase the risk of cancer (they may initiate cancer). Think about it - we are not exposed to just one chemical at a time (which is how chemicals are tested), but to mixtures or a "chemical soup". It is almost impossible to avoid them. As one of the researchers said: "We urgently need to focus more resources to research the effect of low dose exposure to mixtures of chemicals in the food we eat, air we breathe and water we drink." Testing mixtures of chemicals is currently not required by law.

The effects may be synergistic  - an enhanced effect that is more than the sum of the individual chemicals. And some chemicals may have bigger effects at smaller doses (typical of endocrine or hormone disruptors), than at larger doses - which is not how chemicals are typically viewed (typical view: the more you are exposed to a chemical, the greater the effect). A global task force of 174 scientists looked at 85 common everyday chemicals (at everyday low doses), and 50 were found to support cancer-related mechanisms (processes essential to cancer development). Examples of problematic chemicals that are common in everyday life: triclosan (in many soaps and personal care products), bisphenol A (in many plastics, including can linings), and atrazine (common herbicide or weedkiller). From the LA Times:

Combinations of 'safe' chemicals may increase cancer risk, study suggests

Lots of chemicals are considered safe in low doses. But what happens when you ingest a little bit of a lot of different chemicals over time? In some cases, these combinations may conspire to increase your risk of cancer, according to a new report. “Many [chemicals] have the possibility, when they are combined, to cause the initiation of cancer,” said Hemad Yasaei, a cancer biologist at Brunel University in England, one of the authors of the report. “They could have a synergistic or enhanced effect.”

This is not the way regulators typically think about cancer risk when they evaluate a compound’s safety.Normally, they test an individual chemical on laboratory animals, exposing them to progressively smaller amounts until it no longer causes malignant tumors to grow. Then they take that dose, determine the equivalent for humans, and apply what is called a “margin of safety” by declaring that some small fraction of that low dose is safe for people.

The big assumption driving the margin of safety is that a smaller amount of a chemical is less dangerous than a larger amount. (Think of the familiar axiom, “The dose makes the poison.”) But that’s not true for all chemicals, experts say. Some chemicals, such as those that mimic hormones, may actually be more dangerous at lower doses because the human body is exquisitely attuned to respond to minute amounts of natural hormones such as estrogen and testosterone.

And regulators haven’t required testing of mixtures of chemicals at all...Leroy Lowe, president of Canadian nonprofit Getting to Know Cancer and leader of the report published this week by the journal Carcinogenesis. The new report raises questions about whether this approach is adequate...Humans are exposed to about 80,000 man-made chemicals over their lifetimes, experts say. These chemicals are in the foods we eat, the water we drink and the air we breathe. "We live in a chemical soup,” said toxicologist Linda Birnbaum, director of the National Institute of Environmental Health Sciences, who was not involved in the new study.

The research team — a coalition of 174 researchers from 28 countries — set out to determine whether mixtures of these chemicals, at the very tiny concentrations found in the environment, could plausibly trigger the formation of cancerous tumors. They focused on 85 particular chemicals that were impossible to avoid in modern life, that were likely to disturb biological function and were not thought to pose cancer risks at the very low doses that people tend to ingest them.

The researchers scoured the scientific literature to understand how each of these chemicals could affect 10 important processes that are essential to cancer development. Among them: tumor-promoting inflammation, resistance to cell death and the formation of new blood vessels to feed malignant cells. In addition, they categorized whether each of the chemicals exerted biological effects at very low doses to which humans are ubiquitously exposed. (These doses are so small that they tend to be measured in parts per million or parts per billion.)
Of the 85 chemicals researchers examined, 50 were found to affect cancer-causing processes in the body, even at very low doses.

These 50 everyday chemicals included bisphenol A (used in manufacturing plastics), triclosan (often found in hand sanitizer and anti-bacterial soap) and atrazine (a commonly used herbicide). Since each of these chemicals affects different processes that could lead to cancer — bisphenol A makes cells less sensitive to signals to stop reproducing, for example, while atrazine encourages inflammation — it’s plausible that consuming mixtures of these chemicals is riskier than consuming any one individually.

More details about this report. From Science Daily: Cocktail of common chemicals may trigger cancer

There is growing evidence that women around a lot of endocrine disrupting chemicals at home or in jobs such as cleaners, hairdressers and laboratory workers during pregnancy are more likely to have baby boys with a genital defect called hypospadias (a condition where the opening of the urethra is on the underside of the penis rather than at the tip). From Environmental Health News:

Genital defect in baby boys linked to moms’ chemical exposure

Mothers around a lot of endocrine disrupting chemicals at home or in jobs such as cleaners, hairdressers and laboratory workers during pregnancy are more likely to have baby boys with a genital defect, according to a new study in the south of France.The study adds to mounting evidence that fetal exposure to chemicals that mimic people’s natural hormones may cause hypospadias, a condition where the opening of the urethra is on the underside of the penis rather than at the tip.

French researchers examined more than 600 children in the south of France and found that babies exposed to endocrine disrupting chemicals while their genitals were developing were more likely to suffer from hypospadias. Half the boys had hypospadias and half did not. The risk for those exposed was 68 percent higher than the unexposed boys. The researchers ruled out baby boys with known genetic risks for such defects.

The defect, which can be minor or quite severe depending on how far the opening is from the tip, can lead to problems with urination and, later in life, sexual difficulty....It is one of the most common genital defects in baby boys, and most cases require surgery, often done before they reach two years old. In the United States, an estimated five out of 1,000 boys are born annually with hypospadias, while Europe’s rate is slightly less than two out of 1,000.

The researchers estimated the unborn babies’ exposure by looking at their parents’ jobs and where they lived. Working with hormone disrupting chemicals and living in homes near heavy polluters were both linked to more baby boys having the defect. However, the researchers did say a limit of the study was attempting to estimate fetal exposure to such chemicals.Mothers were most likely to have boys with hypospadias if they worked as a cleaner, hairdresser or beautician.  

Some of the endocrine disrupting chemicals linked to the professions involved in the study were bisphenol-A (BPA), phthalates, polychlorinated compounds, alkylphenolic compounds and organic solvents. Most exposures—78 percent—occurred in the window of development when babies’ genitals are forming.... but detergents, pesticides, and cosmetics accounted for 75 percent of the cases,” the authors wrote in the study published in the European Urology journal this month.

Other possible causes of the birth defect include older, obese mothers, and fertility or hormone treatments during pregnancy, according to the U.S. Centers for Disease Control and Prevention.

This wasn’t the first time scientists have found a link between certain chemicals and hypospadias. Mothers in southeast England who were heavily exposed to endocrine disrupting phthalates on the job were about three times as likely to have a baby boy with hypospadias. Phthalates are used in some cosmetics, fragrances, food packaging and PVC plastics.

Finding endocrine disrupting chemicals in 2 out of 10 baby teethers, which are supposedly safe products for babies, is disturbing. Unfortunately the study did not give the manufacturers names. There was even an 11th teether made of natural rubber that was found to leach compounds that were "cytotoxic"(toxic to living cells), but the manufacturer recalled the product before the study results were published. One of the teethers leaching parabens was made of EVA plastic filled with a cooling gel, and the researchers thought the parabens came from the gel used. Note that this study occurred in Europe where the regulations regarding endocrine disrupting chemicals are stricter than in the USA. The researchers themselves suggest that manufacturers should use "green chemistry" when manufacturing products - that is, design products without using problem ingredients right from the start. Problem solved. From Science Daily:

Endocrine disrupting chemicals in baby teethers

In laboratory tests, two out of ten teethers, plastic toys used to sooth babies' teething ache, release endocrine disrupting chemicals. One product contains parabens, which are normally used as preservatives in cosmetics, while the second contains six so-far unidentified endocrine disruptors

"The good news is that most of the teethers we analyzed did not contain any endocrine disrupting chemicals. However, the presence of parabens in one of the products is striking because these additives are normally not used in plastic toys," says Dr. Martin Wagner, of the Department Aquatic Ecotoxicology at the Goethe University. The substances detected -- methyl, ethyl and propyl parabens -- can act like natural oestrogen in the body and, in addition, inhibit the effects of androgens such as testosterone. The EU Commission recently banned two parabens in certain baby cosmetics, because of concerns over their health effects.

"Our study shows that plastic toys are a source of undesirable chemicals. Manufacturers, regulatory agencies and scientists should investigate the chemical exposure from plastic toys more thoroughly," Wagner concludes from the study. The additives have only limited benefits for the quality of the product, but can represent a potential health issue. This is especially true for babies and infants, whose development is orchestrated by a delicately balanced hormonal control and who are more susceptible to chemicals exposures than adults.

Depressing because the 4 chemicals (benzene, toluene, ethylbenzen, xylene) are so pervasive in indoor air. And now to find that at levels considered "safe" by the EPA there may be disruption of our hormones (endocrine systems). Of course they are already known to have health effects on the human body other than what is discussed in this study. For example, toluene has a number of central nervous system effects. The EPA says toluene , which is found in highest concentrations in indoor air from the use of common household products (paints, paint thinners, adhesives, synthetic fragrances, and nail polish). Outside - the biggest source of toluene is from automobile emissions. Some ways to lower exposure to these 4 chemicals: read product labels and when using a product that says to use with proper ventilation - open the windows and let the room ventilate!  Don't smoke. (For example: the EPA says tobacco smoke contains benzene and accounts for nearly half the national exposure to benzene) The study researchers themselves said the EPA should be paying more attention to these air contaminants. I read this at Scientific American, but it came from EHN:

Scientists warn of hormone impacts from benzene, xylene, other common solvents.

Four chemicals present both inside and outside homes might disrupt our endocrine systems at levels considered safe by the U.S. Environmental Protection Agency, according to an analysis released today.

The chemicals – benzene, toluene, ethylbenzene and xylene – are ubiquitous: in the air outside and in many products inside homes and businesses. They have been linked to reproductive, respiratory and heart problems, as well as smaller babies. Now researchers from The Endocrine Disruption Exchange (TEDX) and the University of Colorado, Boulder, say that such health impacts may be due to the chemicals’ ability to interfere with people’s hormones at low exposure levels“There’s evidence of connection between the low level, everyday exposures and things like asthma, reduced fetal growth,” said Ashley Bolden, a research associate at TEDX and lead author of the study. “And for a lot of the health effects found, we think it’s disrupted endocrine-signaling pathways involved in these outcomes.”

Bolden and colleagues – including scientist, activist, author and TEDX founder Theo Colborn who passed away last December – pored over more than 40 studies on the health impacts of low exposure to the chemicals.They looked at exposures lower than the U.S. Environmental Protection Agency’s reference concentrations for the chemicals, which is the agency’s estimated inhalation exposure level that is not likely to cause health impacts during a person’s lifetime.

Many of the health problems – asthma, low birth weights, cardiovascular, disease, preterm births, abnormal sperm – can be rooted in early disruptions to the developing endocrine system, Bolden said. The analysis doesn’t prove that exposure to low levels of the chemicals disrupt hormones. However, any potential problems with developing hormone systems are cause for concern.

“Hormones are how the body communicates with itself to get work done. Interrupt that, you can expect all sorts of negative health outcomes,” said Susan Nagel an associate professor at the University of Missouri-Columbia Obstetrics, Gynecology and Women's Health School of Medicine who was not involved in the study.

The four chemicals are retrieved from the wellheads during crude oil and natural gas extraction and, after refining, are used as gasoline additives and in a wide variety of consumer products such as adhesives, detergents, degreasers, dyes, pesticides, polishes and solvents. Ethylbenzene is one of the top ten chemicals used in children’s products such as toys and playground equipment, according to a 2013 EPA report. Toluene is in the top ten chemicals used in consumer products such as fuels and paints, the report found. 

All four get into indoor and outdoor air via fossil fuel burning, vehicle emissions and by volatizing from products. Bolden said studies that measure the air in and around homes and businesses find the chemicals 90 to 95 percent of the time. In several of the monitoring studies Bolden and colleagues examined, levels of the chemicals were higher in indoor air than in outdoor air, suggesting that people might be exposed within their homes. “A lot of time indoor air is poorly circulated,” Bolden said.

The following study raises the question  of how to lower BPA levels in all people, not just children with autism spectrum disorder.

The absolute quickest and easiest is to buy (whenever possible) loose foods (fresh fruits, vegetables, breads, etc) or foods in glass containers (and not plastic bottles, jars, or containers), store food in glass, porcelain, or stainless steel containers, and microwave in glass dishes (and not plastic containers).

In other words, think glass and not plastic. This is because BPA is in polycarbonate containers or packaging.

Lower your use of canned foods and avoid soda in cans. This is because cans have a lining that contains BPA or a BPA substitute (and research suggests it has the same effects as BPA). By the way, clear cling wrap made from polyethylene is considered safe to wrap and store food in.

From Medical Express: New study links BPA exposure to autism spectrum disorder

A newly published study is the first to report an association between bisphenol-A (BPA), a common plasticizer used in a variety of consumer food and beverage containers, with autism spectrum disorder (ASD) in children. The study, by researchers at Rowan University School of Osteopathic Medicine (RowanSOM) and Rutgers New Jersey Medical School (NJMS), shows that BPA is not metabolized well in children with ASD. The research appears online in Autism Research.

"It has been suspected for a lot of years that BPA is involved in autism, but there was no direct evidence," said T. Peter Stein, of RowanSOM and the study's lead author. "We've shown there is a link. The metabolism of BPA is different in some children with autism than it is in otherwise healthy children."

The research team – which included Margaret Schluter and Robert Steer, of RowanSOM who were responsible for laboratory analysis, and child neurologist Xue Ming, of NJMS who recruited and ascertained the study populations – examined urine specimens from 46 children with ASD and 52 healthy control children for both free BPA and total BPA concentrations.

Like many chemicals, BPA becomes water soluble when it is bound to glucose in the liver – a process called glucuronidation. Conversion to a glucuronide and then excretion of the glucuronide in the urine is a major pathway for removing toxins from the body.

The researchers also conducted a metabolomic analysis to screen for all the chemicals found in the children's urine. The metabolomics analyses showed the mean number of statistically significant correlations between metabolites detected and total BPA excreted to be approximately three times greater with the ASD group than the controls, and the number of statistical significant correlations with fraction of BPA bound was approximately 15 times higher in the children with ASD (p<0.001).

"Other studies involving rodent data have shown that BPA functions as an endocrine disruptor, but ours is the first to show this in humans and the first to associate it to autism," Stein said. "The observations show that for some children there was a relationship between intermediary metabolism, the ability to conjugate BPA and symptoms of autism."

Although the study involves a relatively small number of subjects, Stein said, "The key point is that the study seems to link BPA to autism and creates an open area for further research. One implication of our study is that there might be a benefit to reducing BPA exposure for pregnant women and for children with autism."