1.2- Dibromoethane in water

Vogel TM, Reinhard M. 1986. Reaction products and rates of disappearance of simple bromoalkanes, 1,2-dibromopropane, and 1,2-dibromoethane in water. Environ Sci Technol 20 992-997. 

The third access was based on the reaction of 1,2-dibromoethane with 2-mercapto-purin-9-one or 2-mercaptoadenine and their derivatives. Preparation of compound 83 from potassium or sodium 2-mercaptoinosine (84) with an excess of 1,2-dibromoethane in water exemplified the first reaction according to Scheme 22. The annulation site of thiazole to purine moieties was proven by desulfuration with Raney-nickel (after previous cleavage of the saccharide grouping) by the appearance of 1-ethylhypoxanthine (74CPB342). An example for the second reaction was the cyclization of 2-mercaptoadenine with an excess of dibromoethane giving a mixture of 3,6,7,9-tetrahydro-9-iminothiazolo[3,2-u]purine (85) and isomeric 4-amino-7,8-dihydro-thiazolo[2,3-7>]purine (86). Both isomers were separated by their much different insolubility in chloroform (80JHC583) (Scheme 23). 

Vogel, T.M. and M. Reinhard. Reaction Products and Rates of Disappearance of Simple Bromoalkanes, 1,2-Dibromopropane, and 1,2-Dibromoethane in Water, Environ. Sci. Technol, 20(10) 992-997 (1986). 

You can be exposed to low levels of 1,2-dibromoethane in drinking water (especially well water) and in air. Before EPA stopped the use of 1,2-dibromoethane as a pesticide, the most common way you would have been exposed was by eating food that had very... 

The federal government has set standards and guidelines to protect people from the potential health effects of 1,2-dibromoethane in drinking water, food, and air. EPA recommends that no more than 0.008 ppm of 1,2-dibromoethane should be present in drinking water that is consumed for up to 10 days. EPA does not allow any 1,2-dibromoethane to be in food. Companies must report to EPA if they spill 1,000 pounds or more of 1,2-dibromoethane. 

In another liver foci study using Sprague-Dawley (Crl CD) rats, 1,2-dibromoethane in corn oil given by gavage was used as an initiator. Two dose regimens were used 75 mg/kg 1,2-dibromoethane at 0 and 24 hours or corn oil at 0 hours and 75 mg/kg 1,2-dibromoethane at 24 hours. Partial hepatectomies and phenobarbital in drinking water also were part of the protocol. With this system, at 16 months, 1,2-dibromoethane-exposed rats had increased numbers of foci of hepatic cellular alteration. Rats that received the two doses of 1,2-dibromoethane had increased numbers of nodules on hematoxylin and eosin-stained sections as well as increased number and size of GGT positive foci (Moslen 1984). These results indicate that 1,2-dibromoethane can act as an initiator. 

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. 

Dibromoethane is a halogenated aliphatic hydrocarbon produced when gaseous ethylene comes in contact with bromine. The mixing of ethylene and bromine is accomplished in a variety of ways. One of the more common manufacturing processes involves a liquid-phase bromination of ethylene at 35°-85°C. After the bromination of ethylene, the mixture is neutralized to free acid and then purified by distillation. Other methods of 1,2-dibromoethane formation include the hydrobromination of acetylene and a reaction of 1,2-dibromoethane with water (Fishbein 1980 HSDB 1989). 

Biotic and abiotic degradation of 1,2-dibromoethane in surface waters is slow relative to volatilization of the compound to the atmosphere (ERA 1987b). 1,2- Dibromoethane is resistant to hydrolysis (Jaber et al. 1984) the hydrolytic half-life of the compound has been reported to range from 2.5 years (Vogel and Reinhard 1982) to 13.2 years (HSDB 1989). As a result of its hydrolytic stability and the limited biological activity in subsurface soils, 1,2- dibromoethane leached to groundwater is expected to persist for years. 

High-resolution GC equipped with an appropriate detector is the most common analytical technique for determining the concentrations of 1,2-dibromoethane in air, water, wastewater, soil, leaded gasoline, and various foods (e.g., grains, grain-based foods, beverages, and fruits). The choice of a particular detector will depend on the nature of the sample matrix, the detection limit, and the cost of the analysis. Because volatile organic compounds in environmental samples may exist as complex mixtures or at very low concentrations, concentrations of these samples prior to quantification are... 

Gas purging and trapping is the most commonly used method for the preconcentration of 1,2-dibromoethane from water, waste water, soil, and various foods. This method also provides a preliminary separation of 1,2-dibromoethane from other less volatile and nonvolatile components in the samples, thereby alleviating the need for extensive separation of the components by a chromatographic column prior to quantification. 

The international, national, and state regulations and guidelines regarding 1,2-dibromoethane in air, water, and other media are summarized in Table 7-1. 

Weintraub, R.A. Jex, G.W. Moye, H.A. "Degradation of 1,2-Dibromoethane in Florida Ground Water and Soil, American Chemical Society 189th National Meeting, PEST 110, Florida, 1985. 

For the determination of 1,2-dibromoethane (EDB) and l,2-dibromo-3-chloropro-pane (DBCP) in water by hexane microextraction and GC... 

Dibromoethane can enter your body after you eat or drink contaminated food and water. It can also enter your body through your skin when you bathe or swim in contaminated water. The 1,2-dibromoethane inside tiny soil particles may enter your body if you crush or eat contaminated soil. The chemical can enter your nose and lungs when you breathe air that contains 1,2-dibromoethane or when you shower with water that is contaminated. Near hazardous waste sites or near areas that once were farmed, the most likely way that you will be exposed is by drinking contaminated groundwater. 

Oral exposure of rodents to 1,2-dibromoethane either via gavage or drinking water has resulted in neoplasms of the forestomach and other organs. 

There are two drinking water studies of 1,2-dibromoethane that further support the conclusion that oral exposure to 1,2-dibromoethane results in forestomach tumors in mice. 

In another drinking water study, 50 mg/kg/day 1,2-dibromoethane was used as a positive control for a study on humic acids (Van Duuren et al. 1986). Both sexes of B6C3Fi mice exposed to... 

No studies were located in humans regarding the oral absorption of 1,2-dibromoethane. However, there is evidence to suggest that oral absorption occurs in humans. Death and poisoning resulting from suicide attempts (Olmstead 1960 Saraswat et al. 1986) and from consumption of contaminated fruits, grains, and drinking water (ERA 1983), indicate that absorption occurred. 

The available data suggest that 1,2-dibromoethane may be absorbed dermally by humans. Thus, contact with water contaminated with 1,2-dibromoethane may result in absorption. 

Doses that cause acute death in humans and animals are relatively large. For humans, reports of death following oral exposure were a result of intentional ingestion of a high concentration of 1,2-dibromoethane. Human death following dermal and inhalation exposure occurred in two accidentally-exposed workers. It is therefore highly unlikely that there would be a risk to humans of death under conditions of low-level, long-term exposure from contaminated food or water. 

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