Abstract
The transforming activity of sodium fluoride was studied in the SHE and the BALB/3T3 cell culture systems. Initiating and promoting activities were then investigated by means of the orthogonal methodology. Sodium fluoride was found to induce morphological transformation of SHE cells seeded on a feeder layer of X-irradiated cells at high concentrations (75-125 micrograms/ml). When the cells were seeded in the absence of a feeder-layer, the transformation frequencies increased in a dose-dependent manner with the concentrations of sodium fluoride ranging from 0 to the highly toxic concentration of 200 micrograms/ml. In the BALB/3T3 cell system, sodium fluoride was negative in the standard Kakunaga procedure, while through the experiment designed by table L8 (2(7] of the orthogonal method, an initiating-like effect and a weak promoting activity were detected within the concentrations ranging from a 25 micrograms/ml to a 50 micrograms/ml concentration which is highly toxic for BALB/3T3 cells. From these results, it is suggested that, besides a genetic mode of action, sodium fluoride could possibly act through a non-genotoxic mechanism.
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Long-term exposure to fluoride in drinking water and sister chromatid exchange frequency in human blood lymphocytes
The genetic toxicity of fluoride has been investigated extensively by various test systems. However, results obtained have been inconsistent. Fluoride has been reported to be non-genotoxic, genotoxic, and synergistic or antagonistic with certain mutagens. To date, there are no published human studies on the genotoxicity of fluoride. The purpose of
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Cytogenetic effects of sodium fluoride
Sodium fluoride (NaF) is widely used for the prevention of dental caries at various concentrations. The clastogenic effect of NaF has been tested by the use of several cytogenetic assay systems, but the findings on its genotoxicity are not consistent. In this study, the effects of NaF on chromosomes, unscheduled
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Genotoxic evaluation of sodium fluoride and sodium perborate in mouse bone marrow cells
The LD50 was obtained as the geometric mean of the determined experimental data on mice lethality. The value for sodium fluoride was 32 mg/kg and for sodium perborate the result was 775 mg/kg. The results concerning the SCE rate induced by sodium fluoride are shown in Table 1. Although no
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Increased incidence of melanotic tumors in two strains of Drosophila Melanogaster following treatment with sodium fluoride
In Drosophila melanogaster the frequency of adults with melanotic tumors increases both when .larvae from genetically normal and genetically melanotic tum0r strains are exposed to nutrient containing silver nitrate. Larval nutrient containing sodium fluoride also has this effect on genetically normal individuals. The present work was performed to test simultaneously
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Sodium fluoride promotes morphological transformation of Syrian hamster embryo cells
Sequential treatment of Syrian hamster embryo (SHE) cells with a chemical carcinogen followed by sodium fluoride (NaF) resulted in a higher yield of morphologically transformed cell colonies than treatment of the cells with carcinogen alone. For example, cells treated with benzo[a]pyrene (B[a]P; 3 micrograms/ml) for 3 days, then with NaF
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Fluoride/Osteosarcoma Link Is Biologically Plausible
The "biological plausiblility" of a fluoride-osteosarcoma link is widely acknowledged in the scientific literature. The biological plausibility centers around three facts: 1) Bone is the principal site of fluoride accumulation, particularly during the growth spurts of childhood; 2) Fluoride is a mutagen when present at sufficient concentrations, and 3) Fluoride can stimulate the proliferation of osteoblasts (bone-forming cells).
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Fluoride & Liver Cancers in NTP Bioassay
On October 28, 1988, Battelle Columbus Laboratories submitted its Final Report to the NTP concerning the results of the Mouse study. The principal finding of Battelle's report was that a dose-dependent increase of a rare liver cancer (hepatocholangiocarcinoma) had occurred in the fluoride-treated male and female mice.
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A Critique of Gelberg's Study on Fluoride/Osteosarcoma in New York
The case-control study by Gelberg, published first as a PhD dissertation and then later in two peer-reviewed journals, may represent the most substantive study on fluoride/osteosarcoma previous to Bassin’s 2001 analysis. In assessing Gelberg’s data, we were at first struck by the existence of several notable errors in both the thesis and papers. While these errors do raise questions about the study, our primary concern with Gelberg’s work relates to the methods she used to analyze her data.
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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's Mutagenicity: The "Oral Health Research Institute's" Studies
Although many in vitro and in vivo studies have detected mutagenic effects from fluoride exposure, the Oral Health Research Institute at Indiana University's School of Dentistry has repeatedly failed to find any such effect in multiple studies on the subject.
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