The object of this study was the mutagenic effect of hydrogen fluoride, cryolite and their mixtures on chromosomes of cells of animals subjected to the inhalation of these compounds and also the mutagenic effect of sodium fluoride on cells of human leucocyte cultures.
An increase from 1.24 (in the control) to 6.5% in the frequency of cells with structural chromosome aberrations was observed in the bone marrow of albino rats after 5 months treatment with cryolite at a 3.0 mg/m3 concentration. After the treatment with a mixture of 0.5 mg/m3 of cryolite and 0.05 mg/m3 of hydrogen fluoride for 5 months the increase was from 1.24 (in the control) to 5.9%. Chromatid-type aberrations prevailed.
No increase in the frequency of cells with translocations was observed in testes of mice subjected for 2 months to the inhalation with hydrogen fluoride at a 0.1 mg/m3 concentration, cryolite at a 0.5 mg/m3 concentration and the mixture of 0.05 mg/m3 HF and 0.25 mg/m3 cryolite.
The 2 hours treatment of human lymphocytes in vitro with sodium fluoride at concentrations of 1 x 10-3 and 3 x 10-2 M at the G-stage of the cell cycle did not induce any chromosomal aberrations. Higher concentrations of NaF induced a cytostatic effect.
On the grounds of the results obtained during our experiments F compounds are able to produce certain changes in chromosomes from somatic cells of animals treated in vivo by them… Most of the aberrations observed in the case of bone marrow cells were chromatid-type aberrations… [W]e entertain the opinion that the main damage to chromosomes during our experiments with F compounds also took part during the S-phase… [T]hese data enable us to consider as sufficiently established the conclusion that inorganic fluorine compounds may present a mutagenic danger to human beings.