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Interesting findings - that squirming and fidgeting in ADHD children may be how they learn best and actually aids them in learning. So don't try to stop or suppress the fidgeting and squirming, but instead embrace it. I know of an excellent science teacher who would hand out small chunks of beeswax modeling clay to children who couldn't stop squirming and fidgeting in class - and this helped them focus and learn. From Science Daily:

Kids with ADHD must squirm to learn, study says

For decades, frustrated parents and teachers have barked at fidgety children with ADHD to "Sit still and concentrate!" But new research conducted at UCF shows that if you want ADHD kids to learn, you have to let them squirm. The foot-tapping, leg-swinging and chair-scooting movements of children with attention-deficit/hyperactivity disorder are actually vital to how they remember information and work out complex cognitive tasks, according to a study published in an early online release of the Journal of Abnormal Child Psychology.

The findings show the longtime prevailing methods for helping children with ADHD may be misguided. "The typical interventions target reducing hyperactivity. It's exactly the opposite of what we should be doing for a majority of children with ADHD," said one of the study's authors, Mark Rapport, head of the Children's Learning Clinic at the University of Central Florida. "The message isn't 'Let them run around the room,' but you need to be able to facilitate their movement so they can maintain the level of alertness necessary for cognitive activities."

The study at the UCF clinic included 52 boys ages 8 to 12. Twenty-nine of the children had been diagnosed with ADHD and the other 23 had no clinical disorders and showed normal development. Each child was asked to perform a series of standardized tasks designed to gauge "working memory," the system for temporarily storing and managing information required to carry out complex cognitive tasks such as learning, reasoning and comprehension... A high-speed camera recorded the kids, and observers recorded their every movement and gauged their attention to the task.

Rapport's previous research had already shown that the excessive movement that's a trademark of hyperactive children -- previously thought to be ever-present -- is actually apparent only when they need to use the brain's executive brain functions, especially their working memory.The new study goes an important step further, proving the movement serves a purpose. "What we've found is that when they're moving the most, the majority of them perform better," Rapport said. "They have to move to maintain alertness." By contrast, the children in the study without ADHD also moved more during the cognitive tests, but it had the opposite effect: They performed worse.

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Scientists warn about endocrine disruption from 4 common chemicals in an analysis just released. This is absolutely depressing because the 4 chemicals (benzene, toluene, ethylbenzene, xylene) are so pervasive in indoor air. Especially that at levels considered "safe" by the EPA there may be disruption of our hormones (endocrine systems).

Of course the 4 chemicals 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. 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 the following excerpts are from EHN.

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. ...continue reading "More Problems With Four Common Chemicals"

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The researchers were interested in lifestyle factors that are associated with lower rates of allergies.  Prior research has shown that such lifestyle factors are : living on a farm, introducing fish into the child’s diet at an early age, having pets early in life, parental cleaning of the child’s pacifier by sucking it, crowded living conditions, early daycare attendance, and having siblings. This study found that in households washing dishes by hand, rather than in a dishwasher, there are lower rates of allergies and eczema in children. In addition, the study found that consuming fermented or farm-bought food could decrease the likelihood of allergies further. It is thought that early exposure to microbes stimulates the immune system in beneficial ways. Dishwashers leave fewer bacteria behind on dishes than hand washing dishes. Living in a household that hand-washes means family members are eating off of plates and cutlery that have more bacteria, and therefore they are getting more microbial exposure. There could also be more bacteria in the air when dishes are hand washed or even some other lifestyle factor that these households have in common.From NPR:

Kids, Allergies And A Possible Downside To Squeaky Clean Dishes

Could using a dishwashing machine increase the chances your child will develop allergies? That's what some provocative new research suggests — but don't tear out your machine just yet.The study involved 1,029 Swedish children (ages 7 or 8) and found that those whose parents said they mostly wash the family's dishes by hand were significantly less likely to develop eczema, and somewhat less likely to develop allergic asthma and hay fever.

The findings are the latest to support the "hygiene hypothesis," a still-evolving proposition that's been gaining momentum in recent years. The hypothesis basically suggests that people in developed countries are growing up way too clean because of a variety of trends, including the use of hand sanitizers and detergents, and spending too little time around animals.As a result, children don't tend to be exposed to as many bacteria and other microorganisms, and maybe that deprives their immune system of the chance to be trained to recognize microbial friend from foe.That may make the immune system more likely to misfire and overreact in a way that leads to allergies, eczema and asthma, Hesselmar says.

"The hypothesis was that these different dishwashing methods ... are not equally good in reducing bacteria from eating utensils and so on," Hesselmar says. "So we thought that perhaps hand dishwashing was less effective, so that you are exposed to more bacteria" in a way that's helpful.

In a study released Monday in the online version of the journal Pediatrics, the researchers report what they found: In families who said they mostly wash dishes by hand, significantly fewer children had eczema, and somewhat fewer had either asthma or hay fever, compared to kids from families who let machines wash their dishes.

Still, there are other possible explanations, Hesselmar and Mahr both caution. Though the researchers took economic status into account in the study, it could be that people who don't have dishwashers are alike in some other way that reduces their tendency to get allergies. Interestingly, for example, certain other lifestyle characteristics — eating fermented foods regularly, and tending to buy some foods straight from the farm — seemed to strengthen the "protective" effect in families without dishwashers.

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I was recently asked my thoughts about a nutritionist recommending Benecol spreads, which I actually had never heard of before. After researching Benecol, I looked with horror at all the non-real food ingredients in the various products (for example, Benecol light spread, with 39% vegetable oil, included partially hydrogenated soybean oil, plant stanol esters, various emulsifiers, potassium sorbate, artificial flavor, etc).  I was dismayed because to me it didn't seem like a "real food" - where were the "real" whole food ingredients? For example,consider emulsifiers which recent research says disrupts the "gut microbiome" (the community of microbes living in the gut) and causes inflammation. Which we all know is not good. And partially hydrogenated oils (trans fats) are again a big health no-no. And on and on.

And recently the Academy of Nutrition and Dietetics, an organization that represents some 75,000 registered dietitians and nutritionists, gave its first endorsement (with a "Kids Eat Right" seal of approval) to Kraft American cheese single slices. Huh? Processed cheese (with whey protein concentrate, emulsifiers, sodium citrate, etc.) got an approval seal and not real cheese? What is going on? The answer may lie with the fact that many nutritionists are accepting cash for endorsing certain foods, especially those promoted by big business companies. The latest to be endorsed are cans of Coca Cola soda! From the Tampa Bay Times:

 Coca-Cola paid nutritionists to tout Coke as heart healthy snack

If a column in honor of heart health suggests a can of Coke as a snack, you might want to read the fine print.The world's biggest beverage maker, which struggles with declining soda consumption in the U.S., is working with fitness and nutrition experts who suggest its cola as a healthy treat. In February, for instance, several wrote online pieces for American Heart Month, with each including a mini-can of Coke or small soda as a snack idea.

The mentions — which appeared on nutrition blogs and other sites including those of major newspapers — show the many ways food companies work behind the scenes to cast their products in a positive light, often with the help of third parties who are seen as trusted authorities.

Ben Sheidler, a Coca-Cola spokesman, compared the February posts to product placement deals a company might have with TV shows. "We have a network of dietitians we work with," said Sheidler, who declined to say how much the company pays experts. "Every big brand works with bloggers or has paid talent."

Other companies including Kellogg and General Mills have used strategies like providing continuing education classes for dietitians, funding studies that burnish the nutritional images of their products and offering newsletters for health experts. PepsiCo Inc. has also worked with dietitians who suggest its Frito-Lay and Tostito chips in local TV segments on healthy eating. Others use nutrition experts in sponsored content; the American Pistachio Growers has quoted a dietitian for the New England Patriots in a piece on healthy snacks and recipes and Nestle has quoted its own executive in a post about infant nutrition."

Most of the pieces suggesting mini-Cokes say in the bios that the author is a "consultant" for food companies, including Coca-Cola. Some add that the ideas expressed are their own. One column is marked at the bottom as a "sponsored article," which is an ad designed to look like a regular story. It ran on more than 1,000 sites, including those of major news outlets around the country. The other posts were not marked as sponsored content, but follow a similar format.

Kelly McBride, who teaches media ethics at The Poynter Institute, which owns the Tampa Bay Times, said the phrasing of the disclosure that the author is a "consultant" for food companies, including Coca-Cola, doesn't make it clear the author was specifically paid by Coke for the column."This is an example of opaque sponsored content," McBride said.

The Academy of Nutrition and Dietetics, a professional group for dietitians, says in its code of ethics that practitioners promote and endorse products "only in a manner that is not false and misleading." A spokesman for the academy did not respond when asked if the posts on mini-Cokes meet those guidelines. Meanwhile, a group called Dietitians for Professional Integrity has called for sharper lines to be drawn between dietitians and companies. Andy Bellatti, one of its founders, said companies court dietitians because they help validate corporate messages.

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Research is accumulating that the microbial exposure from a vaginal birth, breastfeeding, and pets in the first year of life are all good for a baby's developing immune system and the gut microbiome.

From Science Daily: Breastfeeding, other factors help shape immune system early in life

Researchers say that breastfeeding and other factors influence a baby's immune system development and susceptibility to allergies and asthma by what's in their gut. The striking findings from a series of studies further advance the so-called hygiene hypothesis theory that early childhood exposure to microorganisms affects the immune system's development and onset of allergies, says Christine Cole Johnson, Ph.D., MPH, chair of Henry Ford's Department of Public Health Sciences and principal research investigator.

The gut microbiome is the collection of microorganisms in the gastrointestional, or GI, tract, and the human body has billions of these microbes... The gut microbiome is known to play an important role in immune system development, and is thought to contribute to a host of diseases like obesity, autoimmune diseases, circulating disorders and pediatric allergies and infection.

"For years now, we've always thought that a sterile environment was not good for babies. Our research shows why. Exposure to these microorganisms, or bacteria, in the first few months after birth actually help stimulate the immune system," Dr. Johnson says."The immune system is designed to be exposed to bacteria on a grand scale. If you minimize those exposures, the immune system won't develop optimally."

In six separate studies, researchers sought to evaluate whether breastfeeding and maternal and birth factors had any effect on a baby's gut microbiome and allergic and asthma outcomes. Using data collected from the WHEALS birth cohort, researchers analyzed stool samples from infants taken at one month and six months after birth. They also looked at whether the gut microbiome impacted the development of regulatory T-cells, or Treg, which are known to regulate the immune system. Highlights:

• Breastfed babies at one month and six months had distinct microbiome compositions compared to non-breastfed babies. These distinct compositions may influence immune system development. • Breastfed babies at one month were at decreased risk of developing allergies to pets. • Asthmatic children who had nighttime coughing or flare-ups had a distinct microbiome composition during the first year of life. • For the first time, gut microbiome composition was shown to be associated with increasing Treg cells.

Researchers found that a baby's gut microbiome patterns vary by: • A mother's race/ethnicity. • A baby's gestational age at birth. • Prenatal and postnatal exposure to tobacco smoke. • Caesarean section versus vaginal delivery.• Presence of pets in the home.

Henry Ford's landmark 2002 study found exposure to dogs or cats in the first year of a baby's life reduced their risk for allergies.

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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."

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Gut bacteria in children varies among different Asian countries. A recent study found that microbiota of 303 subjects could be classified into two main clusters: driven by Prevotella (P-type) or by Bifidobacterium/Bacteroides (BB-type).

The majority of children in China, Japan and Taiwan harbored Bifidobacterium/Bacteroides (BB type), whereas those from Indonesia and Khon Kaen in Thailand mainly harbored Prevotella (P-type). It was interesting in that even eating different types of rice result in different gut bacteria.

From Asian Scientist: Diet, Location And Your Kid’s Gut Bacteria

An Asia-wide study of the gut microbiota of primary school children has identified differences linked to diet and geographical location.  ...continue reading "Gut Bacteria of School Children In Different Asian Countries"

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More than a year after California revised its flame retardant standards so that new furniture (the polyurethane foam in upholstered sofas, sofa beds, and chairs) does not have to use flame retardants, it is still hard to find out whether the furniture is flame retardant free. This is what I have experienced in the last few months - the store doesn't know and the manufacturer won't respond to emails.

The new furniture label should say TB 117-2013 , and then you still need to ask the retailer if there are flame retardants in the upholstered furniture. The new label means that the manufacturer does NOT have to use flame retardant chemicals anymore, but it does NOT mean they are chemical free. And flame retardants are still found in many baby products (car seats, bumpers, crib mattresses, strollers, nursing pillows, etc), some personal care products, and electronics. It's a buyer beware situation.

More and more research is finding health problems with flame retardants because they are "not chemically bound" to the products in which they are used - thus they escape over time, and get into us via the skin (dermal), inhalation (from dust), and ingestion (from certain foods and dust on our fingers). And because flame retardants are persistant, they bioaccumulate (they build up over time). They can be measured in our urine and blood.

Evidence suggests that flame retardants may be endocrine disruptors, carcinogenic, alter hormone levels, decrease semen quality in men, thyoid disruptors, and act as developmental neurotoxicants (when developing fetus is exposed during pregnancy)  so that children have lowered IQ and more hyperactivity behaviors.

How does one know if the foam in your furniture has flame retardants in it? Duke University will test it for free if you send them a small piece of the furniture's foam. http://sites.nicholas.duke.edu/superfund/whats-in-my-foam/ I originally read about this service a few months ago in The Atlantic,

From The Atlantic: How to Test a Couch for Toxins

It began with a smell. Kerri Duntley had just bought a pair of large, cream-colored couches....As the scent continued to fill her living room, Duntley asked herself a troubling question: What was causing the couches to smell like industrial chemicals? The answers weren’t easy to find. Duntley searched in web forums and even tried contacting the couches’ manufacturer. “I called and called and called,” she said. “They just would not give me the information.” She grew frustrated and began looking for new couches. It was then that she discovered an unusual service run by a Duke University lab.

The lab’s offer was simple. First, the lab instructed, wield a pair of scissors. Grab something made with polyurethane foam—say, a mattress or the innards of a couch cushion. Cut a small chunk from the foam. Wrap the surgical work in tinfoil, ziplock seal it and mail the crime-scene-looking evidence off to Durham, North Carolina. Wait up to 45 days, the lab said, and it’ll arrive: a report detailing toxic flame retardants embedded in the foam.

Duntley complied. When the results came back, she learned that her couch sample had tested positive for two flame retardants, including one that has proven harmful in animal studies, a finding that she called heartbreaking. Her experience points to a vast gap in safety information about consumer goods. With the U.S. government’s limited power to regulate chemicals, many consumers, like Duntley, are left to piece together their own crude health-risk assessments. That fabric softener? It may smell like the Elysian Fields, but what if its unlisted ingredients cause cancer? 

Government officials , academic researchers, the chemical industry and environmentalists agree: The U.S. system of chemical regulation is broken. But while the fight over reform continues in Washington, consumers remain blind to many of the chemicals that enter their homes.

Duke’s service is looking in its small way to change that. The lab—which offers anyone a free chemical analysis of polyurethane foam—has informed hundreds of Americans about their furniture’s toxicity. At the same time, the foam samples have given Duke’s team a large bank of crowdsourced research. By offering a free service to an anxious public, Duke’s scientists are gaining a clearer view of chemical manufacturing. And they’re learning just how much we don’t know about the chemicals that enter our homes.

Stapleton was part of a scientific cohort that found ingesting dust—say, getting our dusty hands on a burger—is by far our largest source of exposure to flame retardants; flame retardants aren’t chemically bound to their products, and so they attach themselves to airborne dust.

But what began in California soon became a de facto national standard, since furniture companies didn’t want to manufacture separate lines. Stapleton was interested to see how chemically saturated our furniture really is. So she and her colleagues asked families for samples of their baby products’ foam. After reviewing 101 samples from across thirteen states, Stapleton’s 2011 study reached a startling conclusion: Flame retardants accounted for about 5 percent of the products’ weight, and the chemicals were found in 80 percent of the samples.

Some of the chemicals were carcinogens. Others were from a chemical class known as polybrominated diphenyl ethers, or PBDEs, which have been linked to lower IQ scores, attention deficit hyperactivity disorder, and thyroid disorders. The most common flame retardant among the samples was tris (1,3-dichloroisopropyl)phosphate, or TDCPP, which researchers say is likely to harm the neurological development of infants. TDCPP, in fact, was used throughout the 1970s in children’s pajamas, until critical health research led manufacturers in 1977 to stop using it. Yet the chemical had reemerged in products like strollers and baby mattresses.

The lab offered to test some of these strangers’ furniture for free. But the requests kept coming. That’s when Stapleton and her colleagues decided to expand the scope of the testing and conceived of a free service for the public. They’d test anyone’s polyurethane foam for a suite of seven common flame retardants as something of a public service, since it would be funded by a federal grant (itself funded by taxpayer dollars). The service would also aid Stapleton’s research, offering a valuable stream of crowdsourced data about the chemicals used in furniture.

By crowdsourcing her research, Stapleton has also uncovered a flame retardant that academic literature has yet to identify. The flame retardant is a chlorinated organophosphate, like TDCPP, and its health effects are unknown, she said. Stapleton said that this recent discovery-by-accident followed the same pattern as her research on Firemaster 550, a popular flame retardant that replaced two widespread PBDEs after they were withdrawn from the market... But emerging research has raised concerns about Firemaster 550, too. One study from Boston University and Duke researchers found that the chemical mixture may cause obesity in humans. Stapleton found the same effect in rats.

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Very exciting research. And it's the exact opposite advice that doctors used to tell parents - which was if there was a high risk for a specific allergy that ran in the family (peanuts, dogs, etc.) to have the young child try to avoid exposure to that item (or in the case of peanuts - until the age of 3). From NPR:

Feeding Babies Foods With Peanuts Appears To Prevent Allergies

Babies at high risk for becoming allergic to peanuts are much less likely to develop the allergy if they are regularly fed foods containing the legumes starting in their first year of life. That's according to a big new study released Monday involving hundreds of British babies. The researchers found that those who consumed the equivalent of about 4 heaping teaspoons of peanut butter each week, starting when they were between 4 and 11 months old, were about 80 percent less likely to develop a peanut allergy by their fifth birthday.

"This is certainly good news," says Gideon Lack of King's College London, who led the study. He presented the research at the annual meeting of the American Academy of Allergy, Asthma and Immunology. It was also published in The New England Journal of Medicine.

As many as 2 million U.S. children are estimated to be allergic to peanuts — an allergy that has been increasing rapidly in the United States, Britain and other countries in recent years. While most children who are allergic to peanuts only experience relatively mild symptoms, such as hives, some have life-threatening reactions that can include trouble breathing and heart problems.

Lack's study was launched after he noticed that Israeli kids are much less likely to have peanut allergies than are Jewish kids in Britain and the United States."My Israeli colleagues and friends and young parents were telling me, 'Look, we give peanuts to these children very early. Not whole peanuts, but peanut snacks,' " Lack says. Peanut snacks called Bamba, which are made of peanut butter and corn, are wildly popular in Israel, where parents give them to their kids when they're very young. That's very different from what parents do in Britain and the United States, where fears about food allergies have prompted many parents to keep their children away from peanuts, even though the American Academy of Pediatrics revised a recommendation to do so in 2008.

"That raised the question whether early exposure would prevent these allergies" by training babies' immune systems not to overreact to peanuts, Lack says. "It's really a very fundamental change in the way we're approaching these children." To try to find out, Lack and his colleagues got funding from the U.S. National Institutes of Health to launch a study. They found 640 babies who were at high risk for developing peanut allergies because they already had eczema or egg allergy. They asked half of the infants' parents to start feeding them Bamba, peanut butter, peanut soup or peanut in some other form before their first birthday and followed them for about five years.

"What we found was a very great reduction in the rate of peanut allergy," Lack says. About 17 percent of the kids who avoided peanuts developed peanut allergies, compared with only 3.2 percent of the kids who ate peanuts, the researchers reported.

Based on the findings, Lack thinks most parents should start feeding their babies peanut products as early as possible — not whole peanuts or globs of peanut butter, but peanut mixed in some other food to avoid any possible choking hazard."We've moved, really, 180 degrees from complete avoidance to we should give peanuts to young children actively," Lack says. Other allergy experts hailed the results as an important advance. "This is a major study — really what we would call a landmark study," says Scott Sicherer, who advises the American Academy of Pediatrics on allergies. 

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U.S. government agencies (such as FDA) say phthalates are OK, but evidence is mounting that they definitely are not OK. It's impossible to totally avoid phthalates, but one can lower exposure amounts by eating whole unprocessed foods, not microwaving or storing food in plastic containers (best is glass), and read ingredient lists on labels, including personal care products. From Medical Xpress:

Plastics chemical tied to changes in boys' reproductive development

When expectant mothers are exposed to plastics chemicals called phthalates during the first trimester, their male offspring may have a greater risk of infertility later in life, a new study suggests.Boys exposed to the chemical diethylhexyl phthalate (DEHP) may be born with a significantly shorter anogenital distance than those not exposed to these chemicals. Anogenital distance is the distance between the anus and the genitals. A shorter anogenital distance has been linked to infertility and low sperm count, the researchers explained.

"We saw these changes even though moms' exposure to DEHP has dropped 50 percent in the past 10 years," said lead researcher Shanna Swan, a professor of preventive medicine and obstetrics, gynecology and reproductive medicine at the Icahn School of Medicine at Mount Sinai in New York City. "Therefore, we have not found a safe level of phthalate exposure for pregnant women," she contended.

Swan said that this study cannot prove that these boys will have fertility problems as adults or that DEHP causes these problems. However, animal studies have implicated the chemical in male reproductive problems. Based on the data from this study, Swan believes there is a strong association between exposure to DEHP and fertility in human males.

DEHP is used to soften plastics. Most exposure results from eating foods that pick up the chemical during processing, Swan said. "Since food is the largest source of DEHP for consumers, it is difficult for pregnant women to minimize exposure," she said. "Eating unprocessed food will likely help. However, eliminating DEHP from food really has to be done by food producers."The chemical is also found in medical tubing and in a variety of products, including flooring, wallpaper, lacquers and personal care products, Swan said.

For the study, Swan's team collected data on almost 800 pregnant women and their infants.Specifically, the researchers found that exposure in the womb to three types of DEHP was associated with a significantly shorter anogenital distance in boys, but not in girls.

A group representing the chemical industry took issue with the study, however. In a statement, the American Chemistry Council (ACC) stressed that the study only examined one type of phthalate, not all versions of the chemical... The ACC added that DEHP "is known to break down into its metabolites within minutes after it enters the body. 

But another expert says phthalate exposure may not be benign. Dr. Kenneth Spaeth, director of the Occupational and Environmental Medicine Center at North Shore University Hospital in Manhasset, N.Y., said, "virtually everyone in the U.S. experiences continual exposure to phthalates."And, a number of studies have tied the chemicals with changes in developing fetuses. "Phthalates, in particular, have been shown in both human and animal studies to interfere with normal fetal development," he said.

This study supports what has been demonstrated before, that phthalate exposure in the first trimester is linked to male reproductive development, Spaeth said. "This study is an important step forward in establishing this effect because the study included a much larger number of individuals than prior studies and helps identify one particular agent, DEHP, as an important contributor to this effect," he said.Additionally, this study shows the importance of exposure in the first trimester as a critical window for the effect of phthalates on the male reproductive system.