Abstract
A light and fluorescent microscopy study of sternal and femoral bone marrow, taken from young Swiss mice exposed for up to 280 days to elevated levels of NaF in drinking water, revealed morphologic abnormalities in cell structure and mitotic figure formation in immature leukocytes. Alterations in the content and distribution of RNA and DNA also appeared after several weeks of exposure. These findings, interpreted in relation to other reported data, were compatible with a possible shift of these cells toward anaplasia.
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Sister chromatid exchanges: a study in fluorotic individuals of North Gujurat
The purpose of this preliminary investigation was to compare the genotoxic effect of fluoride in human individuals directly exposed to high concentrations of drinking water fluoride (1.95 to 2.2 ppm) with those in individuals exposed to concentrations (0.6 to 1.0 ppm) within the WHO permissible limit. Sister chromatid exchanges (SCE)
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The mutagenicity of sodium fluoride to L5178Y [wild-type and TK+/- (3.7.2c)] mouse lymphoma cells
L5178Y wild-type and TK+/- (3.7.2c) cells were treated with sodium fluoride over a range of concentrations (10-500 micrograms ml-1) and treatment times (4, 16 and 48 h) covering less than 10-100% survival. The mutant frequency at five genetic loci (resistance to ouabain, 6-thioguanine, excess thymidine, methotrexate and 1-beta-D-arabinofuranosyl cytosine) was
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Clastogenic activity of sodium fluoride in great ape cells
Conflicting evidence has been reported concerning the mutagenicity of sodium fluoride (NaF), especially clastogenicity at concentrations of more than 1 mM. NaF is known to induce chromosome aberrations at these concentrations in human cells, but not in most rodent cells. We considered that such species-specific difference in chromosomal sensitivity would
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Cytogenetic analysis of human lymphocytes of fluorosis-affected men from the endemic fluorosis region in Nalgonda district of Andhra Pradesh, India
Cytogenetic analysis was carried out on human lymphocytes of 73 fluorosis-affected men from the endemic fluorosis region in Nalgonda district of Andhra Pradesh, India, who were drinking water with a mean concentration of fluoride (F) of 4.13± 0.55 mg/L, range 1.56–8. 36 mg/L. Eighty healthy men, of a similar age
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Cytogenetic effects of gaseous fluorides on grain crops
Atmospheric pollution of fluoride from a non-ferrous industrial plant has been studied for its effect on the frequency of chromosome aberrations in root tips and shoot tips of wheat and barley. The anaphase-test was used. The percentage of mutations in the meristematic cells of plants growing in polluted areas was
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Fluoride's Mutagenicity: In vitro Studies
According to the National Toxicology Program, "the preponderance of evidence" from laboratory "in vitro" studies indicate that fluoride is a mutagenic compound. Many substances which are mutagens, are also carcinogens (i.e. they can cause cancer). As is typical for in vitro studies, the concentrations of fluoride that have generally been tested
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NTP Bioassay on Fluoride/Cancer (1990)
In 1977, the U.S. Congress requested that animal studies be conducted to determine if fluoride can cause cancer. The result of the Congressional request was an extensive animal study conducted in the 1980s by the National Toxicology Program (NTP) and published in 1990. The main finding of NTP's study was a dose-dependent increase in osteosarcoma (bone cancer) among the fluoride-treated male rats.
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Micronucleus and Sister Chromatid Exchange Frequency in Endemic Fluorosis
The rise of sister chromatid exchange (SCE) and micronucleus (MN) in the peripheral blood lymphocytes of the fluorine-intoxicated patients indicates that fluorine is a mutagenic agent which can cause DNA and chromosomal damage.
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Fluoride's Mutagenicity: In vivo Studies
Consistent with dozens of in vitro studies, a number of in vivo studies, in both humans and animals, have found evidence of fluoride-induced genetic damage. In particular, research on humans exposed to high levels of fluoride have found increased levels of "sister chromatid exchange" (SCE). As noted in one study: "In
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Fluoride & Osteosarcoma: A Timeline
Several human epidemiological studies have found an association between fluoride in drinking water and the occurrence of osteosarcoma (bone cancer) in young males. These studies are consistent with the National Toxicology Program's (NTP) cancer bioassay which found that fluoride-treated male rats had an dose-dependent increase in osteosarcoma. Although a number of studies have failed to detect an association between fluoride and osteosarcoma, none of these studies have measured the risk of fluoride at specific windows in time, which based on recent results, is the critical question with respect to fluoride and osteosarcoma.
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