Paul working for you.

Friday, February 26, 2021

Lower IQ?

 


New study finds fluoride lowers IQ at exposures similar to artificially fluoridated water and genetics

 can cause heightened vulnerability

The latest epidemiological study finding an association between fluoride exposures and reduced IQ in 

children was at exposures in the same range as occur in areas with artificial water fluoridation.  T

he study by Zhao et al (2021), conducted in China in a large group of 567 children, found substantially 

lower IQ scores amongst those with greater fluoride exposure.  Child urine fluoride levels of 1.5 mg/L 

were estimated to have a -6.5 IQ points* loss compared to children with urine fluoride levels of 0.5 mg/L.

 

The average urine fluoride concentration in the study was 1.0 mg/L, which is only slightly higher than the 

average 0.7 mg/L urine fluoride levels found in studies of people residing in artificially fluoridated parts of 

Canada and the US, and substantially less than the maximum levels [Green 2019, Uyghurturk 2020].  In t

he Canadian study fluoridated water averaged 0.6 mg/L and in the US study it averaged 0.7 mg/L

 

The new Zhao et al study clearly supports FAN’s own recent dose-response assessment of over a dozen 

higher quality studies of fluoride and IQ, which found a consistent statistically significant loss of IQ even at 

exposures of 0.7 mg/L and below.

This new study is also important because it confirms findings from two previous studies which found that 

people with some specific genetic variations affecting neurodevelopment are especially susceptible to loss 

of IQ from fluoride exposure.  Those previous papers were by Zhang et al (2015) and Cui et al (2018), and 

they found 5-fold and 4-fold greater loss of IQ for people with specific variants in two genes.  The new 

paper extends the findings by looking at four different genes simultaneously, and evaluating the interactions

 between the genes and between fluoride and IQ.  All four genes are known to affect neurodevelopment, 

acting through the neurotransmitter and hormone dopamine, according to Zhao et al.  The study found that 

certain combinations of variants in the four genes produced much greater susceptibility to loss of IQ from 

fluoride exposure, similar to what had been found in the single gene studies of Zhang and Cui, but 

revealing a more complicated relationship that depends on interactions between several genes.


Children with susceptible gene variants harmed most

The genetic variations are naturally occurring and each variant typically exists in a sizable proportion of the 

population, so these are not rare genetic conditions associated only with certain rare diseases.  The

technical term for these variants are Single Nucleotide Polymorphisms or SNPs.

 

This is the first time multiple gene effects have been looked at with fluoride neurotoxicity, but the findings 

are not unexpected because similar multiple-gene interactions have been found to effect loss of IQ from the

 neurotoxin mercury.  A large cohort study in England found that children with a combination of the most 

susceptible variants of genes lost a stunning 25 IQ points from higher mercury exposures, whereas the 

overall average loss of IQ for all children with all combinations of variants was too small to even detect

 [Grandjean 2013 video by IAOMT, Julvez & Grandjean 2013, Julvez et al 2013].  If a similar genetic 

dependence of susceptibility to fluoride exists, this may explain why in some fluoride neurotoxicity studies a 

few individual subjects showed much greater effects than the average.  The Bashash 2018 and the  

Green 2019 studies considered these extreme cases as possible outliers, but found that even excluding 

them did not alter the finding that the remaining subjects still showed clear associations between fluoride 

and adverse neurodevelopmental outcomes.

 

The implications for public health policy of genetic variation in vulnerability to fluoride are substantial 

[Julvez & Grandjean 2013].  An exposure level that might produce a relatively small adverse effect on most 

people could be causing a very great adverse effect on a genetically susceptible subset of the population. 

 Regulations to prevent harm must be tailored to the most vulnerable, not the average, because there is no

 practical way to know in advance who is most susceptible and water fluoridation is mass-medication that 

cannot accommodate individual variations in response.

Chris Neurath
Research Director
Fluoride Action Network

2 comments:

  1. Fluoride is a poison. Fluoride was poison yesterday. Fluoride is poison today. Fluoride will be poison tomorrow. Don't be the last one on your block to sign the Fluoride petitions call the Farrell's at 978-939-2501 to arraign a time to sign. When in doubt get it out.

    ReplyDelete
  2. closing schools has a hell of lot more to do with failing kids than does fluoride !!!!! having a bunch of teachers that want to get paid but not work is more of a problem than fluoride ever thought of doing. i have never read about children, 6 to 10 years killing then selves because of fluoride !!!! we have teachers that don't give a damn about children !!!!! they stay home and we pay them !!!! who is the the stupid one here ??? the parents that won't do anything !!!!

    ReplyDelete