How the Next Generation's Brain Functions are Endangered by EDCs and Other Environmental Chemicals by the Collaborative on Health and the Environment Dr. Philippe Grandjean suggests that new scientific insights reveal that the next generation's brain functions are endangered by environmental chemicals. The fetus is not protected by the placenta and therefore shares the mother's cumulated exposures to toxic chemicals. Infants and children are likewise exposed to a cocktail of foreign substances against which the body has no innate defense. Prenatal and early postnatal brain development is an extremely complex process that we now know is uniquely vulnerable. Lead, mercury and a few other substances have long been known to be toxic to brain development. Recent research suggests that many chemicals, perhaps thousands, may cause similar effects because they can gain access to the developing brain and exert their toxicity to brain cells. This new insight needs to be translated into public policy to protect the brain functions of the next generation. On this call Dr. Grandjean discussed what he terms "chemical brain drain" and how we might work to protect the brain health of future generations. Sources: http://www.healthandenvironment.org/partnership_calls/14316?res

1. EDC Strategy
CHE partnership call
Wednesday, April 16th, 2014
Dr. Philippe Grandjean
on Chemical Brain Drain:
How the Next Generation's
Brain Functions are
Endangered by EDCs and
Other Environmental Chemicals
www.chemicalbraindrain.info

2. 1

3. Erroneous and dangerous
assumptions:
• The placenta protects the fetus
• Children are just little adults
• Poisonings are reversible
• Proof is needed for regulation
• Testing is too expensive
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4. Sensitive brain development
• Cell division
In third trimester about 12,000 nerve cells are formed every minute
• Differentiation
• Migration
Distances up to 1,000 times the size of the cell
• Axon formation
Total length by age 20 years: 176,000 / 149,000 km (m/f)
• Generation of synapses
Up to 1,000 new synapses per second early postnatally
• Weeding of synapses
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5. Brain development gone astray
…in every case the mother was healthy,
and it was not until more than three
months after birth that the symptoms
were recognized
Shoji Kitamura (1959)
Photo: W. Eugene Smith
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6. Focal
Widespread
Diffuse
5

7. Percent correct responses on MCAS math test in 4th grade
Exposure limit (CDC)
10 30 50 70
90
70
50
30
Averages for 351
Massachusetts
municipalities:
Children born
in 1992
and 1999
Average blood‐lead (μg/L) at preschool age
(Jessica W. Reyes, 2012)
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8. Chemical brain drainers
Chemical group Known in 2006 Newly identified
Metals/inorganic
Arsenic*
compounds
Lead*
Methylmercury*
Fluoride*
Manganese*
Organic solvents (Ethanol)
Toluene* Tetrachloroethylene*
Pesticides Chlorpyrifos*
DDT/DDE*
Other organic
compounds
Polychlorinated
biphenyls (PCBs)*
Brominated diphenyl
ethers*
Total 6 6
*Endocrine disruptor, according to TEDX
(Grandjean & Landrigan, Lancet Neurology, 2014)
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9. Time of recognition
Neurotoxicant dose (inverted scale)
Number of subjects affected Silent pandemic
Neurotoxicity
In adults Poisoning
incidents
Subclinical effects
in child populations
8
(Grandjean and Landrigan, The Lancet, 2006)

10. Known neurotoxic to humans
during development, N > 10
Neurotoxic to humans N > 200
Neurotoxic
in lab tests N > 1,000
Chemical
universe N ~ 100,000
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(Updated from Grandjean and Landrigan, The Lancet, 2006)

11. The goal: Full integrity of the brain
to allow optimal brain functions
We need it:
The brain
determines
behavior, IQ,
endocrine
functions...
and who we are
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12. What can be done?
• Mothers, consumers can make choices to
decrease exposures
• An OECD test protocol is available to test
for developmental neurotoxicity
• New cell-based tests are faster, cheaper
• Regulation of EDCs
• Chemicals control needs to include focus
on brain development
• International clearinghouse
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13. www.chemicalbraindrain.info
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