Genotoxicity clastogens

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

Genotoxicity—A specific adverse effect on the genome of living cells that, upon the duplication of affected cells, can be expressed as a mutagenic, clastogenic or carcinogenic event because of specific alteration of the molecular structure of the genome. 

In summary, genotoxicity studies of endosulfan have provided evidence that this compound is mutagenic and clastogenic, and that it induces effects on cell cycle kinetics in two different mammalian species. However, some of these data may be suspect because some formulations of endosulfan have contained epichlorohydrin, a known genotoxic chemical, as a stabilizer (Hoechst 1990). It should be noted that humans may also be exposed to epichlorohydrin along with endosulfan. 

Likewise, the related zeolite mineral clinoptolite is an active stimulant of macrophage chemiluminescence (Velichkovsky et al., 1983). Evidence of the genotoxic and clastogenic activity of erionite to cultured cells has also been presented (Poole et al., 1983 Kelsey et al., 1986). 

While many of the studies on genotoxicity of disulfoton were negative, the positive results indicate a potential for mutagenic and clastogenic effects in humans exposed to disulfoton. 

It has been suggested that phenol exposure results in cardiac effects because it blocks the cardiac sodium channel subtype, with little effect on sodium channels in skeletal muscle (Zamponi et al. 1994). Phenol does not appear to be carcinogenic following oral exposure (NCI 1980), although the chemical combinations that result from benzene and phenol metabolism may contain compounds that do initiate or promote cancer. Metabolites such as hydroquinone and catechol have been demonstrated to be genotoxic and clastogenic. 

In view of the limited and somewhat conflicting evidence for the carcinogenicity of 1,2-dibromoethane in exposed human populations, data on the clastogenic and genotoxic effects in humans could offer insight into potential human health risks from 1,2-dibromoethane. 

Thiram was genotoxic to insects, plants, fungi, and bacteria it induced sister chromatid exchange and unscheduled DNA synthesis in cultured human cells. Despite established genotoxicity in vitro, it showed no clastogenic and/or aneugenic activity in vivo after oral administration to mice at the maximum tolerated dose. ... 

Vinyl chloride was genotoxic in a variety of in vitro assays. It is also reportedly mutagenic and clastogenic in humans. Increased frequencies of chromosomal aberrations, micronuclei, and sister chromatid exchanges have been found in the peripheral blood lymphocytes of workers exposed to high levels of vinyl chloride. ... 

Trichlorophenol may exhibit weak aneugenic and clastogenic activity. Information on other chlorophenols is inadequate to allow assessment of their genotoxicity. 

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