A study of 145 preschool children reports, for the first time, that when the concentrations of two common phthalates in mothers’ prenatal urine are elevated their sons are less likely to play with male-typical toys and games, such as trucks and play fighting.

The University of Rochester Medical Center-led study is published in the International Journal of Andrology.

Because testosterone produces the masculine brain, researchers are concerned that fetal exposure to anti-androgens such as phthalates “which are pervasive in the environment“ has the potential to alter masculine brain development, said lead author Shanna H. Swan, Ph.D., professor of Obstetrics and Gynecology, director of the URMC Center for Reproductive Epidemiology, and an expert in phthalates.

“Our results need to be confirmed, but are intriguing on several fronts,” Swan said. “Not only are they consistent with our prior findings that link phthalates to altered male genital development, but they also are compatible with current knowledge about how hormones mold sex differences in the brain, and thus behavior. We have more work to do, but the implications are potentially profound.”

Phthalates are chemicals used to soften plastics. Recent studies have shown that the major source of human exposure to the two phthalates of most concern (DEHP and DBP) is through food. These phthalates are used primarily in polyvinyl chloride (PVC), so any steps in the processing, packaging, storage, or heating of food that use PVC-containing products can introduce them into the food chain.

Phthalates are also found in vinyl and plastic tubing, household products, and many personal care products such as soaps and lotions. Phthalates are becoming more controversial as scientific research increasingly associates them with genital defects, metabolic abnormalities, and reduced testosterone in babies and adults. A federal law passed in 2008 banned six phthalates from use in toys such as teethers, play bath items, soft books, dolls and plastic figures.

In Swan’s study, higher concentrations of metabolites of two phthalates, di(2-ethylhexyl) phthalate (DEHP), and dibutyl phthalate (DBP), were associated with less male-typical behavior in boys on a standard play questionnaire. No other phthalate metabolites measured in-utero was linked to the less-masculine behavior. Girls’ play behavior was not associated with phthalate levels in their mothers, the study concluded.

Swan’s interest in phthalates stems from an investigation into the environmental causes of reproductive health problems. Since 1998 she has led the federally funded, multi-center Study for Future Families (SFF), which established a large database from which to explore various scientific questions about toxins.

The current study focused on a small sample of SFF mothers who delivered children between 2000 and 2003. The mothers provided urine samples around the 28th week of pregnancy. The urine was analyzed for phthalate metabolites by the Centers for Disease Control and Prevention (CDC).

Swan hypothesized that phthalates may lower fetal testosterone production during a critical window of development – somewhere within eight to 24 weeks gestation, when the testes begin to function – thereby altering brain sexual differentiation.

To explore the question, researchers reconnected with mothers from the SFF sample and asked them to complete a standard research questionnaire, called the Preschool Activities Inventory (PSAI), for their children ages 3 1/2 to 6 1/2 years.

The PSAI is designed to discriminate play behavior within and between the sexes, and in the past has been shown to reflect the endocrine-disrupting properties of other toxins, such as PCBs and dioxins. The PSAI addressed three aspects of play: types of toys children choose (trucks versus dolls), activities (rough-and-tumble play, for example), and child characteristics.

However, researchers were concerned about how the choice of toys available in any given household might skew results, so in addition they asked about parental views toward atypical play. For example, the survey asked, “What would you do if you had a boy who preferred toys that girls usually play with?” The possible answers included “strongly encourage” (him to play this way) to “strongly discourage.”

The final survey scores are designed to reflect sex-typical play. Higher scores meant more male-typical play and lower scores meant more female-typical play.

Researchers then examined boys play-behavior scores in relation to the concentration of phthalate metabolites in their mothers’ prenatal urine samples, finding that higher concentrations of DEHP and DBP metabolites were associated with less masculine play behavior scores.

Earlier studies by Swan and others have shown that phthalate exposure during pregnancy might affect the development of genitals of both male rodents and baby boys. Scientists refer to this cluster of genital alterations as the “phthalate syndrome,” and research suggests that in rodent pups, the syndrome can have adverse consequences for later sexual development.

If endocrine disrupters such as phthalates can impair genital development and hormone levels in the body, the play-behavior study noted, then a deeper examination of how these chemicals impact the brain is warranted.

Reference: University of Rochester Medical Center, Pilot study relates phthalate exposure to less-masculine play by boys, Nov. 16, 2009

If it hadn’t been for the Big Macs that Joannie ate pretty much three times a week, she wouldn’t have gotten fat.  If she hadn’t been exposed while in her mother’s womb to chemicals x, y and z, Joannie wouldn’t have had the propensity to get fat.  And if Joannie’s mom had eaten more sensibly, both waistlines would be slimmer.

Fat people most likely are programmed to become fat before taking their first sip of milk.

Today’s news is, that pesticides are among the chemicals responsible for this reprogramming.

Two of three U.S. adults are now classified as overweight.  Type II diabetes has increased in like measure over the same decades, and so has heart disease.  This is not a coincidence.  These illnesses share common characteristics: they are triggered while in the womb by exposure to the same kinds of chemicals and the outcomes show up in adulthood.  Scientists now call this pattern “the fetal origins of adult diseases”.

The most likely culprits are chemicals now grouped together under the rubric “endocrine disrupters.” It’s been known for about two decades, though disputed by the manufacturers, that these chemicals alter the normal signaling pathways of hormones.  Think of Bisphenol A (BPA), right now the nation’s most celebrated endocrine disruptor.

Pesticides, though not specifically thought of as endocrine disruptors nor regulated as such, can similarly knock normal development off track.  Research has just found that a family of pesticides among the most widely used in the world is connected to these three adult illnesses.  This is the family of organophosphates, concocted from petroleum with an addition of phosphoric acid.

When lab rats are exposed to these pesticides through the mother’s diet, at a time in their development equivalent to a human baby’s second trimester in the womb, their metabolism changes in two ways: their cholesterol and triglycerides rise.  These abnormal and lasting changes resemble the major factors that predict and lead, later in life, to obesity, diabetes and cardiovascular heart disease (specifically, atherosclerosis, a condition in which fatty material collects along the arteries and hardens artery walls).

These changes in metabolism happen at low levels, within the levels we are uniformly exposed to, which the Environmental Protection Agency declares as “safe” but are evidently not.  The changes are the strongest when the mother rats are fed a high-fat diet.  Human babies may even be underweight at birth (and there’s an epidemic of underweight babies in the U.S.), but quickly become overweight

Humans run into these pesticides in our food and water.  Of course, children continue to be exposed once they are born and are in fact exposed more than adults because they eat and drink more in relation to their body weight and have a higher ratio of skin.

The other groups of people exposed most to organophosphates and other pesticides are the same groups with the highest rates of obesity – people who live in run-down inner-city neighborhoods, the poor, and farmworkers.  Again, not a coincidence but a connection, a trigger.

Dr. Ted Slotkin of Duke University, the researcher responsible for these discoveries, found another compelling clue: exposure caused harm to the rodent’s brain, as well as its metabolism.  Once the exposed lab animal was born and started to eat at will, its consumption of a high-fat diet reduced the adverse symptoms in its brain functioning.  As Dr. Slotkin muses, “If you’ve got neurofunctional deficits, and they can be offset by continually eating Big Macs, then you will naturally (but unconsciously) select that kind of food because it will make you feel better.”  Unfortunately, increased fat will further harm the animal’s, or human’s, metabolism.

What this means for you:

Particularly while trying to conceive, during pregnancy, while nursing, and for your children, avoid pesticides; eat organic foods.

For information about endocrine disruptors, read the new booklet published by the nonprofit Learning and Developmental Disabilities Initiative.

Author: Alice Shabecoff for CSN – Chemical Sensitivity Network, November 5, 2009

Alice Shabecoff is the co-author with her husband Philip of Poisoned Profits: The Toxic Assault on our Children, published by Random House last year.  See their website, www.poisonedprofits.com

Related article from Alice Shabecoff:

• Our planet, our children – How are your children doing?

Among dietary factors, learning and behavior are influenced not only by nutrients, but also by exposure to toxic food contaminants such as mercury that can disrupt metabolic processes and alter neuronal plasticity. 

Neurons lacking in plasticity are a factor in neurodevelopmental disorders such as autism and mental retardation. Essential nutrients help maintain normal neuronal plasticity. Nutritional deficiencies, including deficiencies in the long chain polyunsaturated fatty acids eicosapentaenoic acid and docosahexaenoic acid, the amino acid methionine, and the trace minerals zinc and selenium, have been shown to influence neuronal function and produce defects in neuronal plasticity, as well as impact behavior in children with attention deficit hyperactivity disorder. 

Nutritional deficiencies and mercury exposure have been shown to alter neuronal function and increase oxidative stress among children with autism. These dietary factors may be directly related to the development of behavior disorders and learning disabilities. 

Mercury, either individually or in concert with other factors, may be harmful if ingested in above average amounts or by sensitive individuals. High fructose corn syrup has been shown to contain trace amounts of mercury as a result of some manufacturing processes, and its consumption can also lead to zinc loss. Consumption of certain artificial food color additives has also been shown to lead to zinc deficiency. Dietary zinc is essential for maintaining the metabolic processes required for mercury elimination.

Since high fructose corn syrup and artificial food color additives are common ingredients in many foodstuffs, their consumption should be considered in those individuals with nutritional deficits such as zinc deficiency or who are allergic or sensitive to the effects of mercury or unable to effectively metabolize and eliminate it from the body. 

Reference:

Dufault R, Schnoll R, Lukiw WJ, Leblanc B, Cornett C, Patrick L, Wallinga D, Gilbert SG, Crider R., Mercury exposure, nutritional deficiencies and metabolic disruptions may affect learning in children, Behav. Brain Funct. 2009 Oct 27;5(1):44.

Twenty-eight incapacitated individuals (average 43 years old, 7 males, 21 females, range 12-70) exposed to molds and mycotoxins were studied and treated with a protocol of cleaning up or changing their environment to be mold free.

Injections of the optimum dose of antigens were given as part of the treatment protocol as was oral and intravenous (i.v.) antioxidants; heat depuration (sauna); physical therapy with massage and exercise under environmentally controlled conditions; oxygen therapy at 4-8 L/min for 2 hours with a special wood-grade cellophane reservoir and a glass oxygen container. Many patients were sensitive to plastics; therefore, exposures to these were kept to a minimum. Autogenous lymphocytic factor (ALF) was given as an immune modulator.

Of 28 patients, 27 did well and returned to work. One patient improved but did not return to work during the period of study

Reference: Rea WJ, Pan Y, Griffiths B., The treatment of patients with mycotoxin-induced disease, Environmental Health Center – Dallas, TX, USA, Toxicol Ind Health. 2009 Oct-Nov;25(9-10):711-4.

A new study in China has found that people with higher levels of pesticide exposure are more likely to have suicidal thoughts. The study was carried out by Dr Robert Stewart from the Institute of Psychiatry at King’s College London together with scientists from Tongde Hospital Zhejiang Province. 

The agricultural pesticides commonly used in China are organophosphates which are in wide use in many lower income countries but have been banned in many Western nations. It is well known that they are very dangerous if ingested as an overdose but there is also biological evidence that chronic low-grade exposure to these chemicals, which are very easily absorbed into the body through the skin and lungs, may have adverse effects on mental health. This study is the first epidemiological evidence to suggest possible effects on suicidal thoughts. 

The study was carried out in central/coastal China, a relatively wealthy area with a rapidly developing economy. In a very large survey of mental health in rural community residents, participants were also asked about how they stored pesticides. The study found that people who stored pesticides at home, i.e. those with more exposure, were more likely to report recent suicidal thoughts. Supporting this, the survey also found suicidal thoughts to be associated with how easily accessible these pesticides were in the home and that the geographic areas with highest home storage of pesticides also had highest levels of suicidal thoughts in their populations. 

Given the high level of pesticide exposure and the high suicide risk in rural China, clarification of the causal mechanisms underlying this association and the development of appropriate interventions should be priorities for public health and health policy. 

Dr Robert Stewart comments: ‘Organophosphate pesticides are widely used around the world although are banned in many countries because of their risk to health. They are particularly lethal chemicals when taken in overdose and are a cause of many suicides worldwide. Our research findings that suggest that higher exposure to these chemicals might actually increase the risk of suicidal thoughts provides further support for calls for tighter international restrictions on agricultural pesticide availability and use.’

Dr Jianmin Zhang, Associate Chief Psychiatrist, Tongde Hospital of Zhejiang Province, and Vice Director, Zhejiang Office of Mental Health, China added: “The findings of this study suggested potential causal links and might partially account for the much higher incidence of suicide in rural than urban areas of China. However, further studies particularly with more precisely defined and assessed exposure are critically needed, as awareness of safer access to pesticides is important both to policy-makers and pesticide users.”

Reference: King’s College London, Pesticides exposure linked to suicidal thoughts, October 22, 2009  

Notes:

Pesticide exposure and suicidal ideation in rural communities in Zhejiang province, China by Jianmin Zhang, Robert Stewart, Michael Phillips, Qichang Shi & Martin Prince was published in the October issue of the WHO Bulletin. The full article can be accessed on http://www.who.int/bulletin/volumes/87/10/08-054122.pdf 

The analysis involved data from a survey of a representative sample of 9,811 rural residents in Zhejiang province who had been asked about the storage of pesticides at home and about whether or not they had considered suicide within the two years before the interview. The Chinese version of the 12-item General Health Questionnaire (GHQ) was administered to screen for mental disorder.