1.2- Dibromoethane response

Cell proliferation, predominantly in the proximal tubules, occurred in Wistar rats following a single oral dose of 100 mg/kg 1,2-dibromoethane in corn oil. Mitotic activity peaked at 30 hours. Lack of any histologic evidence of tubular necrosis between 8-48 hours after treatment indicates that such proliferation was not a regenerative response (Ledda-Columbano et al. 1987b). 

A dose of 103 mg/kg/day for females and 116 mg/kg/day for males of 1,2-dibromoethane in drinking water induced squamous cell tumors (primarily carcinomas) of the forestomach in male and female B6C3P mice (Van Duuren et al. 1985). It should be noted that the male and female mice were sacrificed before the completion of the chronic study because of excessive morbidity. Because only one dose of 1,2-dibromoethane was used, a dose-response could not be characterized. 

Evidence from animal bioassays supports the hypothesis that it is the cytosolic system and not the microsomal oxidative system that is responsible for the carcinogenicity of 1,2-dibromoethane. 

Intense room-temperature phosphorescence was obtained with 1,2 di-bromoethane (0.6 M) as heavy-atom perturber. The phenomenon was observed with 18 PNA [192] and 16 azaaromatics containing one or two heterocyclic nitrogens [193]. The formation of a three-component complex, CD/aromatic/dibromoethane, in which the aromatic and the heavy-atom perturber are organized in a small space, is believed to be responsible for the phosphorescence emission. It was found that, concomitant with phosphorescence emission, the fluorescence of the included aromatic was quenched. It should be noted that, for most of the aromatics examined, a residual phosphorescence emission was found also in air-equilibrated solutions. 

Nonlinear isotherms have been reported particularly at low Cg values (Fig. 3.10a). The sorption of both dibromoethane (EDB) and the herbicide diuron (DUN) on a peat soil (49.3%OC) both show this response, which is more pronounced with the latter. A similar type of response is also observed in soils of lower organic carbon content. A competitive effect is also demonstrated with trichloroethylene and phenol suppressing the sorption of EDB and EDB (at a sufficient concentration), monuron and dichlorophenol affecting the sorption of diuron. The... 

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