Abstract
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 the melanotic tumorigenic
capacity of sodium fluoride in two different genetic lines in which such tumors normally occur or do not occur with appreciable frJ1quency.
. . . .
In D. Melanogaster, when larvae are grown in nutrient containing different concentrations of NaF, the tu-soj strain, which normally has a relatively strong genetic predisposition for the formation of melanotic tumors, demonstrates a significantly higher rate of induced melanotic tumors in the adult stage than does the wild·type Oregon R strain, which normally has a relatively weak genetic predisposition in this respect.
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Genotoxic evaluation of chronic fluoride exposure: micronucleus and sperm morphology studies
The purpose of this study was to investigate the genotoxic effects of chronic fluoride exposure on mammalian cells in vivo by use of the mouse bone-marrow micronucleus test and the sperm morphology methodology. Mice of genotype B6C3F1 were obtained at weaning and maintained on a low-fluoride diet (less than 0.2
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Genotoxic evaluation of sodium fluoride in the Somatic Mutation and Recombination Test (SMART)
In this study, genotoxic effect of sodium fluoride (NaF) was investigated in Drosophila melanogaster Somatic Mutation and Recombination Test. Third-instar larvae trans-heterozygous for two genetic markers mwh and flr, were treated at different concentrations (2.5 microg/ml, 5 microg/ml and 10 microg/ml) of the test compounds. After the treatment the observed
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Differential in vivo genotoxic effects of lower and higher concentrations of fluoride in mouse bone marrow cells.
In an in vivo genotoxicity investigation of the action of fluoride (F) on bone marrow cells, sodium fluoride (NaF) was administered through the drinking water of 2–3 month old Swiss albino mice for 30 days at lower (7.5, 15, and 30 mg/L) and higher concentrations (100 and 150 mg/L). Mitotic
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Effects of melatonin and amla antioxidants on fluoride-induced genotoxicity in human peripheral blood lymphocyte cells
This investigation reports genotoxic effects of sodium fluoride (NaF) at 17, 34, and 51 ?M for 72 hr and induction of sister chromatid exchanges (SCEs) and related changes, together with ameliorative effects by melatonin and amla, in human peripheral blood lymphocyte cell cultures. The cell cycle proliferative index (CCPI) significantly
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Lack of effect of prior treatment with fluoride on genotoxicity of two chemical agents in vitro
The goal of this study was to investigate the ability of fluoride to modulate the genotoxic effects induced by the oxidative agent hydrogen peroxide (H2O2) and the alkylating agent methyl methanesulfonate (MMS) in vitro by the single-cell gel (comet) assay. Chinese hamster ovary cells were exposed in culture for 1
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Fluoride & Osteosarcoma: A Timeline
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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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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 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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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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