Abstract

Studies on the effects of HF on meiotic chromosomes of tomatoes indicated a trend toward a higher frequency of chromosomal aberrations with an increase in the fumigation period. It was indicated that HF was capable of inducing paracentric inversions with the possibility of the induction of deficiencies, duplications or even translocations. The progeny obtained from the treated plants produced a number of abnormal phenotypes, the same as, or similar to, known mutations. Further studies in maize microsporocytes for plants treated with HF confirmed the cytological results obtained in tomatoes with clear evidence of the occurrence of inversions, translocations and deficiencies. These results suggest that HF seems to affect primarily the DNA molecule by blocking its replication, probably through its action on the enzymatic system.

• Related Studies :

  • The influence of atmospheric hydrogen fluoride on the frequency of sex-linked recessive lethals and sterility in Drosophila Melanogaster

    The influence of hydrogen fluoride as an atmospheric contaminant was investigated in the Oregon-r strain of Drosophila melanogaster. Two principal parameters of mutagenicity were used: sex-linked recessive lethals and sterility. The flies were subjected to various levels of HF in fumigation chambers. Sex-linked recessive lethal mutation frequency increasd at each level

  • 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

  • Genotoxic effect and rat hepatocyte death occurred after oxidative stress induction and antioxidant gene downregulation caused by long term fluoride exposure

    Studies focusing on possible genotoxic effects of excess fluoride are contradictory and inconclusive. Currently, studies have reported a probable link to oxidative stress, DNA damage and apoptosis induced by fluoride in rat hepatocytes. We developed an in vivostudy administering three doses of fluoride by gavage given to rats for 60 day.

  • Ameliorative effects of N-acetylcysteine on fluoride-induced oxidative stress and DNA damage in male rats' testis

    This study was to elucidate DNA damage in rats treated with sodium fluoride (NaF) by performing 8-Hydroxy-2-deoxyguanosine (8-OHdG) immunohistochemical staining assays on seminiferous tubules of rats' testis, and also to evaluate the protective effects of N-acetylcysteine (NAC) on spermatogenesis. Male Sprague Dawley (SD) rats were exposed to a single dose

  • DNA damage, apoptosis and cell cycle changes induced by fluoride in rat oral mucosal cells and hepatocytes

    AIM:  To study the effect of fluoride on oxidative stress, DNA damage and apoptosis as well as cell cycle of rat oral mucosal cells and hepatocytes. METHODS:  Ten male SD rats weighing 80-120 g were randomly divided into control group and fluoride group, 5 animals each group. The animals in

• Related FAN Content :

  • 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. 

  • 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.

  • 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.

  • 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

  • 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.