Gene mutation assays bacterial

The genotoxic potency of ethyl chloride appears to be low. It was negative in in vivo micronucleus tests, but it has produced both positive and negative results in bacterial gene mutation assays. ... 

In general, genotoxicity standard assays (e.g., bacterial reverse mutation assay [Ames test], in vitro chromosomal aberration assay, mouse lymphoma gene mutation assay, and rodent micronucleus assay) may not be suitable assays because the test cells do not contain the appropriate receptors to transport the product (i.e.,not a relevant species) or because the biopharmaceutical... 

The potential for interaction with genetic material (and therefore risk of carcinogenicity) can be investigated using bacterial and mammalian gene mutation assays and chromosomal aberration assays. The parent CDs do not exhibit mutagenic behavior in any of these assays, and there have been no reports of tumors in oral feeding studies or in the parenteral administration of any of the parent CDs. 

Nickel compounds are generally negative in bacterial gene mutation assays, but positive responses have often been found in in vitro mammalian cell assays. 

No genotoxic activity of European mistletoe was observed in a variety of assays, including a bacterial mutation assay, mammalian cell gene mutation assay, in vitro cytogenetic assay, cell transformation assay, and the Ames test (Mengs 1998 Mengs et al. 1997). 

Cerium sulfide pigments also show no genotoxic or carcinogenicity effects. Bacterial and in vitro gene mutation assays (OECD 471 476) fail to show mutagenic activity. In vitro chromosomal aberration tests (OECD 473) show no clastogenic activity. Additionally, sub-chronic toxicity (28 day, OECD 407) studies show no significant adverse effects (dose of 150 mg/kg/day), unlike cadmium and some other pig-ments . ... 

Furfural was genotoxic in vitro in mammalian cells, causing chromosomal aberrations, gene mutations, and sister chromatid exchanges it was not mutagenic in a number of bacterial assays. ... 

Heptachlor was not mutagenic in bacterial assays, but it did cause gene mutations in rodent cells and unscheduled DNA synthesis in human fibroblasts. ... 

The bacterial and mammalian cell assays for gene mutation were developed to measure statistically significant increases in the numbers of mutant colonies derived from rare events many millions of exposed cells must be plated out to allow the assessment of mutation frequency. The Salmonella typhimurium reverse mutation assay ( Ames test) is carried out in a variety of different mutant strains selected to identify the various classes of mutation. The test generates many hundreds of Petri dishes for counting and is not practical for profiling. 

IPEC-US (intended clinical route)a Acute oral and dermal toxicity, skin and eye irritation, and skin sensitization. Bacterial gene mutation and chromosome damage. ADME (intended route). 28-day toxicity (2 species by intended clinical route) Short-term use studies. 90-day toxicity (most appropriate species). Teratology (rat and/or rabbit). Genotoxicity assays. Additional assays (conditional) 1 Short-/midterm studies. One-generation reproduction. Chronic toxicity (rodent and nonrodent) and carcinogenicity (conditional)... 

DIPE has been tested for genotoxic activity in bacterial mutation assays, a yeast assay for mitotic gene conversion, and in tests using rat liver and Chinese hamster ovary cells with structural chromosome damaging the end point. Negative responses were observed in the bacterial and yeast assays. 

It was positive for gene mutations (HGPRT and TK genes) as well as for chromosomal aberrations, sister chromatid exchange, and DNA repair-deficient bacterial assays. 

Cytogenetic examination of bone marrow cells showed no increase in aberrations in maternal and neonatal rats following maternal oral exposure to a DeBDE and NoBDE mixture. In vitro assays found that DeBDE did not induce gene mutations in several bacterial tests (Ames assays) or in mammalian cells. DeBDE also did not induce chromosomal aberrations in Chinese hamster ovary cells. However, exposure to the congeners 2,2, 4,4 -tetra-BDE, 3,4-diBDE, and 2-monoBDE caused increased recombinogenic activity at the HGPRT locus in several cell lines. 

Mixed results were observed for in vitro tests of pyrene. Negative results were obtained for pyrene in DNA damage assay in Escherichia coli and Bacillus subtilis. Both positive and negative results were observed in bacterial gene mutation test. Pyrene did not induce an increase in sex-linked recessive lethal gene in Drosophila. It increased the incidence of mitotic gene conversion but not other genetic endpoint in yeast. 

CR is stated not to be genotoxic in a Salmonella bacterial mutagenicity test, a CHO forward gene mutation test (HGPRT locus), mouse lymphoma cell assay (L5178Y/tk+/tk ), and a micronucleus test (Colgrave et al, 1983). 

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