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Note: The following is a limited selection of abstracts from 1994
Due to length, we present this as a separate section
When time allows more information will be added.
report available at: http://www.fluoride-journal.com/00-33-2/332-74.pdf
of high fluoride water on intelligence of children
(a), ZR Sun (a), LN Wu (a), X Wang, (a), W Lu (a), SS Liu (b)
(a) Dr Yan Lu, Department
of Environmental Health, Tianjin Medical University, Tianjin, China.
(b) Tianjin Xiqing District Anti-Epidemic Station, Tianjin, China.
SUMMARY: The Intelligence
Quotient (IQ) was measured in 118 children, aged 10-12 years, who
were life-long residents in two villages of similar population size
and social, educational and economic background but differing in
the level of fluoride in drinking water.
The children in the high-fluoride area (drinking
water fluoride 3.15 ± 0.61 mg/L [ppm]) (mean ±
S.D.) had higher urinary fluoride levels
(4.99 ± 2.57 mg/L) than the children in the low-fluoride
area (drinking water fluoride 0.37 ± 0.04 mg/L) (urinary
fluoride 1.43 ± 0.64 mg/L).
The IQ of the 60 children in the high-fluoride
area was significantly lower, mean 92.27 ± 20.45,
than that of the 58 children in the low-fluoride
area, mean 103.05 ± 13.86. More children in the high-fluoride
area, 21.6%, were in the retardation (<70) or borderline
(70-79) categories of IQ than children in the low
fluoride area, 3.4%. An inverse relationship was also present
between IQ and the urinary fluoride
level. Exposure of children to high levels
of fluoride may therefore carry the risk of impaired development
of a High Fluoride Water Supply on Children's Intelligence
LB, Liang GH, Zhang DN, Wu XR Lu-Liang
Public Health Bureau, Shanxi 033000, China.
In Shanxi Province, China, children living in the endemic fluoride
village of Sima (water supply F = 4.12
mg/L) located near Xiaoyi City had average IQ (97.69) significantly
lower (p < 0.02) than children living to the north in the nonendemic
village of Xinghua (F = 0.91 mg/L;
average IQ = 105.21). These differences were not associated with
gender, but the IQ scores were directly related to educational level
of the parents.
of fluoride exposure on intelligence in children
(a), Zhi JL (b), Gao RO (c)
(a) Guizhou Provincial
Sanitary and Anti-epidemic Station, Guiyang City, 550001, China
(b) Anshun Prefecture Sanitary and Anti-Epidemic Station
(c) Zhijin County Sanitary and Anti-Epidemic Station
Summary: The intelligence
was measured of 907 children aged 8-13 years living in areas which
differed in the amount of fluoride present in the environment.
The Intelligence Quotient (IG) of children living in areas with
a medium or severe prevalence of fluorosis was lower than that of
children living in areas with only slight fluorosis or no fluorosis.
The development of intelligence appered to be adversely affected
by fluoride in the areas with a medium or severe prevelence of fluorosis
but to a minor extent only in areas with only a slight prevalence
of fluorosis. A high fluoride intake was associated
with a lower inteligence. No correlation was found between
age and intelligence in the areas with a medium and severe prevalence
of fluorosis. The effect of exposure to a high level of fluoride
on intelligence may occur at an early stage of development of the
embryo and infant when the differentiation of brain nerve cells
is occurring and development is most rapid.
Hua Xi Yi Ke Da Xue Xue
Bao 1994 Jun;25(2):188-91
excessive fluoride intake on mental work capacity
of children and a preliminary study of its mechanism]
[Article in Chinese]
Li Y, Li X, Wei S.
We made an investigation in 157 children, aged 12-13, born and grew
up in a coal burning pattern endemic fluorosis area and an experiment
on excessive fluoride intake in rat. The results showed:
(1) Excessive fluoride intake since early
childhood would reduce mental work capacity (MWC) and hair zinc
(2) The effect on zinc metabolism was a mechanism
of influence on MWC by excessive fluoride intake;
(3) Excessive fluoride intake decreased 5-hydroxy
indole acetic acid and increased norepinephrine in rat brain; whether
this is also a mechanism of the influence on MWC awaits confirmation.
PMID: 7528715 [PubMed - indexed for MEDLINE]