Chromosome aberration and sister chromatid exchange tests in chinese hamster ovary cells in vitro. V: Results With 46 Chemicals

Abstract

Forty-six coded chemicals were tested for their ability to induce sister chromatid exchanges (SCEs) and chromosomal aberrations (ABs) in cultured Chinese hamster ovary (CHO) cells using a standard protocol with and without exogenous metabolic activation. Sixteen chemicals were negative and 15 were positive in both assays; 15 were positive for SCEs only (one chemical that was positive for SCEs was equivocal for ABs), and no chemicals induced ABs only. The effect of cell harvest time on the ability to detect the induction of ABs was examined for 18 chemicals. Seven chemicals produced a positive response using both standard and extended harvest times, five were positive only using an extended harvest time, and six were negative using both harvest times. The relationship between cell cycle delay and SCE induction was also examined, and the two appear to be unrelated.

High Frequency of Ras Mutations in Forestomach and Lung Tumors of B6C3F1 Mice Exposed to 1-Amino-2,4-dibromoanthraquinone for 2 Years

“…Suggested mechanisms for A G transitions include adduct formation and deamination (22,34). Our ndings of A to T transversions or A to G transitions in foretomach and lung tumors provide a further understanding of ADBAQ-induced carcinogenesis at the molecular level and are consistent with the mutagenic assays in vitro (10,17,19). A similar pattern of K-ras mutations in the second base of codon 61, CAA to CTA or CGA has been observed in mouse pulmonary tumors induced by ethyl carbamate or vinyl carbamate (16).…”

Richtwerte für Ethylacetat in der Innenraumluft

“…5020 mg/l) in einem Test zu einer schwach erhöhten Rate an Schwesterchromatidaustauschen, in einem zweiten Test mit S9-Mix wurde ebenso wie ohne S9-Mix kein derartiger Effekt festgestellt. In derselben Studie wurden in Anund Abwesenheit von S9-Mix keine Chromosomenaberrationen in CHO-Zellen induziert [39]. In Lungenfibroblasten des Chinesischen Hamsters traten bei hohen Konzentrationen (7000 mg/l) Chromosomenaberrationen einschließlich "gaps" auf [1,3,40].…”

2‐Methoxyethanol [MAK Value Documentation in German language, 2009]

“…503 mg 2-Methoxyethylacetat/ml beobachtet (Loveday et al 1990). Ein Chromosomenaberrationstest an CHO-Zellen war mit metabolischer Aktivierung ab 1,5 mg 2-Methoxyethylacetat/ml positiv und ohne metabolische Aktivierung bis 5 mg 2-Methoxyethylacetat/ml negativ (Loveday et al 1990). …”