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Children's brain development being harmed by chemicals in the environment - both before birth and in childhood -  is such an important topic that here are excerpts from two articles about the same report that was just released (in Lancet Neurology).  From Time:

Children Exposed to More Brain-Harming Chemicals Than Ever Before

In recent years, the prevalence of developmental disorders such as autism, attention deficit/hyperactivity disorder (ADHD) and dyslexia  have soared. While greater awareness and more sophisticated diagnoses are partly responsible for the rise, researchers say the changing environment in which youngsters grow up may also be playing a role.

In 2006, scientists from the Harvard School of Public Health and the Icahn School of Medicine at Mount Sinai identified five industrial chemicals responsible for causing harm to the brain — lead, methylmercury, polychlorinated biphenyls (found in electric transformers, motors and capacitors), arsenic (found in soil and water as well as in wood preservatives and pesticides) and toluene (used in processing gasoline as well as in paint thinner, fingernail polish and leather tanning). Exposure to these neurotoxins was associated with changes in neuron development in the fetus as well as among infants, and with lower school performance, delinquent behavior, neurological abnormalities and reduced IQ in school-age children.

Now the same researchers have reviewed the literature and found six additional industrial chemicals that can hamper normal brain development. These are manganese, fluoride, chlorpyrifos, dichlorodiphenyltrichloroethane, tetrachloroethylene and polybrominated diphenyl ethers. Manganese, they say, is found in drinking water and can contribute to lower math scores and heightened hyperactivity, while exposure to high levels of fluoride from drinking water can contribute to a seven-point drop in IQ on average. The remaining chemicals, which are found in solvents and pesticides, have been linked to deficits in social development and increased aggressive behaviors.

But they say the growing body of research that is finding links between higher levels of these chemicals in expectant mothers’ blood and urine and brain disorders in their children should raise alarms about how damaging these chemicals can be. The developing brain in particular, they say, is vulnerable to the effects of these chemicals, and in many cases, the changes they trigger are permanent. The consequence of such brain damage is impaired [central nervous system] function that lasts a lifetime and might result in reduced intelligence, as expressed in terms of lost IQ points, or disruption in behavior,” they write in their report, which was published in the journal Lancet Neurology.

Same report, from Science Daily: Growing number of chemicals linked with brain disorders in children

"The greatest concern is the large numbers of children who are affected by toxic damage to brain development in the absence of a formal diagnosis. They suffer reduced attention span, delayed development, and poor school performance. Industrial chemicals are now emerging as likely causes," said Philippe Grandjean, adjunct professor of environmental health at HSPH.

The study outlines possible links between these newly recognized neurotoxicants and negative health effects on children, including:  - Manganese is associated with diminished intellectual function and impaired motor skills  - Solvents are linked to hyperactivity and aggressive behavior - Certain types of pesticides may cause cognitive delays.

Grandjean and co-author Philip Landrigan, Dean for Global Health at Mount Sinai, also forecast that many more chemicals than the known dozen or so identified as neurotoxicants contribute to a "silent pandemic" of neurobehavioral deficits that is eroding intelligence, disrupting behaviors, and damaging societies. But controlling this pandemic is difficult because of a scarcity of data to guide prevention and the huge amount of proof needed for government regulation. "Very few chemicals have been regulated as a result of developmental neurotoxicity," they write.

The authors say it's crucial to control the use of these chemicals to protect children's brain development worldwide. They propose mandatory testing of industrial chemicals and the formation of a new international clearinghouse to evaluate industrial chemicals for potential developmental neurotoxicity.

Take note: all of us are exposed to these contaminants because they are in our environment.  The Inuit exposure is just more concentrated. From Feb. 7, 2014 Environmental Health News:

Contaminants have variety of effects on Arctic baby IQs

Babies in Arctic Canada are at risk of specific effects on their mental abilities, depending on which contaminants they are exposed to in the womb, according to a new study.While lead, methylmercury and polychlorinated biphenyls (PCBs) all are linked to neurological effects, each seems to have a different effect on infants, the scientists concluded. For example, PCBs seemed to impair the babies’ ability to recognize things they have seen.

The study involved 94 Inuit infants and their mothers from Nunavik, in northern Quebec. PCBs, mercury and other pollutants hitchhike north via prevailing winds and currents from industrialized areas, and then accumulate in food webs, predominantly in the eastern Arctic. Because the Inuit in Canada and Greenland eat top predators such as beluga whales and seals, they are among the world’s most contaminated human beings. The scientists measured the babies’ prenatal exposure to the three contaminants by testing cord blood, and then administered standard mental development tests at 6.5 months and 11 months. 

“Each contaminant was independently associated with impairment of distinct aspects of cognitive function with long-term implications for cognitive development PCBs with visual recognition memory, methylmercury with working memory and an early precursor of executive function, lead with processing speed – deficits that can already be detected during the first year of life,” the authors wrote.

For the research, scientists at Quebec’s Centre de Recherche du CHUQ, who have been studying effects of contaminants on Inuit children for two decades, teamed up with Wayne State University scientists who conducted groundbreaking work in the Great Lakes linking PCBs to reduced IQs in the 1990s.

 Well, it looks like the researchers devised a nutritional supplement, which they then tested and found beneficial effects on the thinking processes of older adults - so some bias there, but still interesting. What was in the supplement they called NT-020? Extracts of blueberries, green tea, vitamin D3, and amino acids such as carnosine. Science Daily:

Nutritional supplement improves cognitive performance in older adults, study finds

Now a University of South Florida (USF) study reports that a formula of nutrients high in antioxidants and other natural components helped boost the speed at which the brains of older adults processed information.

The USF-developed nutritional supplement, containing extracts from blueberries and green tea combined with vitamin D3 and amino acids, including carnosine, was tested by the USF researchers in a clinical trial enrolling 105 healthy adults, ages 65 to 85. The two-month study evaluated the effects of the formula, called NT-020, on the cognitive performance of these older adults, who had no diagnosed memory disorders.

Those randomized to the group of 52 volunteers receiving NT-020 demonstrated improvements in cognitive processing speed, while the 53 volunteers randomized to receive a placebo did not. Reduced cognitive processing speed, which can slow thinking and learning, has been associated with advancing age, the researchers said. Blueberries, a major ingredient in the NT-020 formula, are rich in polyphenols, a type of antioxidant containing a polyphenolic, or natural phenol substructure.

In several preclinical trials, researchers gave aging laboratory rats NT-020 to see if it boosted memory and other cognitive performance by promoting the health of neurons in the aging brain. Those studies demonstrated that NT-020 promoted the growth of stem cells in the brain, produced an overall rejuvenating effect, benefited animals with simulated stroke, and led to better cognitive performance.

The study results suggest that the effect of higher levels of omega-3 fatty acids on brain volume is the equivalent of delaying the normal loss of brain cells that comes with aging by one to two years. The researchers suggest that these higher levels can be achieved through diet or the use of supplements (about 1000 mg of EPA + DHA daily, or by eating a portion of fish such as salmon or sardines every day).  From the January 22, 2014 Science Daily:

Can fish oil help preserve brain cells?

People with higher levels of the omega-3 fatty acids found in fish oil may also have larger brain volumes in old age equivalent to preserving one to two years of brain health, according to a study published in the January 22, 2014, online issue of Neurology, the medical journal of the American Academy of Neurology. Shrinking brain volume is a sign of Alzheimer’s disease as well as normal aging.

For the study, the levels of omega-3 fatty acids EPA+DHA in red blood cells were tested in 1,111 women who were part of the Women’s Health Initiative Memory Study. Eight years later, when the women were an average age of 78, MRI scans were taken to measure their brain volume.

Those with higher levels of omega-3s had larger total brain volumes eight years later. Those with twice as high levels of fatty acids (7.5 vs. 3.4 percent) had a 0.7 percent larger brain volume.

Those with higher levels of omega-3s also had a 2.7 percent larger volume in the hippocampus area of the brain, which plays an important role in memory. In Alzheimer’s disease, the hippocampus begins to atrophy even before symptoms appear.

Another positive piece of news for those getting on in years. From Jan. 20, 2014 Science News:

Forget About Forgetting: Elderly Know More, Use It Better

What happens to our cognitive abilities as we age? If your think our brains go into a steady decline, research reported this week in the Journal Topics in Cognitive Science may make you think again. The work, headed by Dr. Michael Ramscar of Tübingen University, takes a critical look at the measures usually thought to show that our cognitive abilities decline across adulthood. Instead of finding evidence of decline, the team discovered that most standard cognitive measures, which date back to the early twentieth century, are flawed. "The human brain works slower in old age," says Ramscar, "but only because we have stored more information over time."

Ramscar and his colleagues' work provides more than an explanation of why, in the light of all the extra information they have to process, we might expect older brains to seem slower and more forgetful than younger brains. Their work also shows how changes in test performance that have been taken as evidence for declining cognitive abilities in fact demonstrates older adults' greater mastery of the knowledge they have acquired.

The Tübingen research conclude that we need different tests for the cognitive abilities of older people -- taking into account the nature and amount of information our brains process. "The brains of older people do not get weak," says Michael Ramscar. "On the contrary, they simply know more."

Researchers found that caffeine enhances memory.From Science Daily:

It's All Coming Back to Me Now: Researchers Find Caffeine Enhances Memory

Michael Yassa, assistant professor of psychological and brain sciences in the Krieger School of Arts and Sciences at Johns Hopkins, and his team of scientists found that caffeine has a positive effect on long-term memory in humans. Their research, published by the journal Nature Neuroscience, shows that caffeine enhances certain memories at least up to 24 hours after it is consumed.

According to the U.S. Food and Drug Administration, 90 percent of people worldwide consume caffeine in one form or another. In the United States, 80 percent of adults consume caffeine every day. The average adult has an intake of about 200 milligrams -- the same amount used in the Yassa study -- or roughly one strong cup of coffee or two small cups of coffee per day.

The importance of 5 healthy behaviors in having the best chance of leading a disease free life. The 5 behaviors are: taking regular exercise, non-smoking, a low body weight, a healthy diet and a low alcohol intake. And as the researchers point out: "healthy behaviors have a far more beneficial effect than any medical treatment or preventative procedure".From Science Daily:

35 Year Study Finds Exercise Reduces Risk of Dementia

The study identifies five healthy behaviors as being integral to having the best chance of leading a disease-free lifestyle: taking regular exercise, non-smoking, a low body weight, a healthy diet and a low alcohol intake.

The people who consistently followed four or five of these behaviors experienced a 60 per cent decline in dementia and cognitive decline -- with exercise being the strongest mitigating factor -- as well as 70 per cent fewer instances of diabetes, heart disease and stroke, compared with people who followed none.

"The size of reduction in the instance of disease owing to these simple healthy steps has really amazed us and is of enormous importance in an aging population," said Principle Investigator Professor Peter Elwood from Cardiff University's School of Medicine. "What the research shows is that following a healthy lifestyle confers surprisingly large benefits to health -- healthy behaviors have a far more beneficial effect than any medical treatment or preventative procedure.

The Caerphilly Cohort Study recorded the healthy behaviors of 2,235 men aged 45-59 in Caerphilly, South Wales.