Clastogenic effects, testing

Differently, and in agreement with previous findings (De Marco et al. 1995, 1999), both MN and AAT were observed in all treatments with MH (Fig. 1), including the positive control (H20 treatment). However, with respect to the positive control, the treatment with MH alone at different concentrations produced a significant increase of the clastogenic effect in V. faba, A. cepa and P. sativum (Ferrara et al. 2004) (Fig. 4). The MN and AAT frequencies increased as a function of MH concentration, but the differences were significant at the Duncan s test at P<0.05 only for AAT (Fig. 4). With respect to the positive control, the increases of frequencies measured for V. faba, A. cepa and P. sativum were for MN, respectively up to 9.8, 10 and 14 times, and for AAT, respectively up to 7.6, 2.8 and 1.8 times. 

Herbold B. 1986a. Investigation of p-dichlorobenzene for clastogenic effects in mice using the micronucleus test. Institute of Toxicology. Report No. 14694. 

The test for photoinduced chromosomal aberrations (CA) is another suitable alternative for photogenotoxicity assessment. The clastogenic effects of 8-MOP or 5-MOP under UV irradiation, but not in the dark, in these test systems have been known for many years [30, 62]. More recently, a large study on quinolones using this method has been published [63]. However, this method is relatively labor-intensive. 

Of two types of in vivo tests carried out on mammals—chromosome damage in bone marrow or testes—only the intratesticular injection of Parathion in the guinea pig yielded strongly positive (clastogenic) effects on spermatogonia (ref. 2b, p. 157) ... 

Genotoxic Effects. Genotoxicity studies conducted in a variety of test systems have failed to provide evidence for mutagenicity of zinc. However, there are indications of weak clastogenic effects following zinc exposure. 

Results of in vitro studies are shown in Table 2-5. Exposure to zinc as zinc sulfate or zinc chloride does not increase mutation frequencies in bacterial or mammalian cell culture test systems (Amacher and Paillet 1980 Gocke et al. 1981 Marzin and VO Phi 1985 Nishioka 1975 Thompson et al. 1989 Venitt and Levy 1974 Wong 1988). Similarly, there was no convincing evidence of a clastogenic effect in human lymphocytes exposed to 0.0003-0.00003 M zinc chloride (Deknudt and Deminatti 1978). 

Isoindoline pigments do not exhibit acute toxicity in animal tests by oral and inhala-tive administration. Tests have shown that they do not cause irritation of the skin or mucous membranes. The Ames test for mutagenicity gave negative results, and the test for genotoxicity shows no clastogenic effects. 

The vast majority of in vivo tests show no geno-toxicity of mono- and dialkyltins. Results from in vitro tests are variable, with little indication of DNA reactivity. There are, however, indications of clastogenicity and effects on spindle formation in mitosis in vitro. 

Among the mutagens tested on each plant species (Table 4), those that produced evident clastogenic alterations were (a) MH on V faba, A. cepa, P. sativum, and T. turgidum, (b) COL on V. faba and A. cepa, and (c) ALA on T. turgidum. The effects measured for MH and ALA on T. turgidum, and for 2,4-D and GLY on V faba and A. cepa, were not statistically significant, thus the related data will not be considered further in this section. 

Since cultured cells are normally treated in their usual growth medium, the solubility of the test material in the medium should be ascertained before testing. As pointed out earlier, extremes of pH can be clastogenic (Cifone et al., 1987), so the effect of the test material on pH should also be determined, but buffers can be utilized. 

Equivocal results have been found in geno-toxic assays, but endosulfan was mutagenic and clastogenic and induced effects on cell cycle kinetics in various in vivo and in vitro tests. ... 

Mutagenic potential Test effects on genetic stability and mutations in bacteria (Ames test) or mammalian cells in culture dominant lethal test and clastogenicity in mice. 

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