75-27-4 Bromodichloromethane

Abstr Services Reg.No. 75-27-4 Systematic name Bromodichloromethane 

2 Structural and molecular formulae and relative molecular mass 

Bromodichloromethane is found in chlorinated drinking-water as a consequence of the reaction between chlorine, added during water treatment, and natural organic substances in the presence of bromide. The major route of human exposure is via drinking-water. Bromodichloromethane has also been detected in some untreated waters, but at much lower levels. It is a major component of the organohalides produced by marine algae (lARC, 1991). 

No data were available to the Working Group regarding exposure to bromodichloro- 

After oral administration to rats, bromodichloromethane is rapidly absorbed part of the dose is exhaled as unchanged bromodichloromethane and as CO2, and only minor fractions of the dose are found in the urine. Absorbed bromodichloromethane is rapidly eliminated from experimental animals, mainly by exhalation (lARC, 1991). 

Stokinger HE The halogens and the non-metals boron and silicon. In Clayton GD, Clayton FE (eds) Patty s Industrial Hygiene and Toxicology, 3rd ed, rev, Vol 2B, Toxicology, pp 2965-2968. New York, Wiley-Interscience, 1981 

Henderson Y, Haggard HW Noxious Gases. New York, Reinhold, 1943 

Kraut A, Lilis R Chemical pneumonitis due to exposure to bromine compounds. Chest 94 208-210, 1988 

Potashnik G, Carel R, Belmaker I, et al Spermatogenesis and reproductive performance following human accidental exposure to bromine vapor. Reprod Toxicol 6 171-174, 1992 

Woolf A, Shannon M Reactive airways dysfunction and systemic complaints after mass exposure to bromine. Environ Health Perspect 107(6) 507-509, 1999 

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Chlorine. Chlorine is a weU known disinfectant for water and wastewater treatment, however, it can react with organics to form toxic chlorinated compounds such as the tribalomethanes bromodichloromethane, dibromochloromethane, chloroform [67-66-3] and bromoform [75-25-2]. Chlorine dioxide [10049-04-4] may be used instead since it does not produce the troublesome chlorinated by-products as does chlorine. In addition, by-products formed by chlorine dioxide oxidation tend to be more readHy biodegradable than those of chlorine, however, chlorine dioxide is not suitable for waste streams containing cyanide. 

Trihalomethanes. Wherever chlorine is used as a disinfectant in drinking-water treatment, trihalomethanes (THMs) generaUy are present in the finished water. The THMs usuaUy formed are trichloromethane (chloroform), bromodichloromethane, dibromochloromethane, and tribromomethane (bromoform). There are four main techniques for the analysis of THMs headspace, Hquid— Hquid extraction (Ue), adsorption—elution (purge—trap), and direct aqueous injection. The final step in each technique involves separation by gas—Hquid chromatography with a 2 mm ID coUed glass column containing 10 wt % squalene on chromosorb-W-AW (149—177 p.m (80—100 mesh)) with detection generaUy by electron capture. 

Halogenared aliphatic hydrocarbons Bromobenzene C arbondichloride Chlorofluoroethene Dibromoerhane Hexachlorobutadiene Trifiuoroethene Bromodichloromethane C hloroform... 

The following compounds were determined by this procedure chloroform bromoform 1,1,1-trichloroethane 1,1,2,2-tetrachloroethane trichloroethylene benzene carbon tetrachloride toluene bromodichloromethane chlorobenzene 1,1,2-trichloroethane o,p-xylene tetrachloroethylene o,p-chlorotoluene 1,2-dibromoethane and fluorobenzene (used as an internal standard). 

We mentioned in Chapter 2 (Section 2.6.1) that a purge-and-trap procedure sometimes precedes an analysis by gas chromatography. An example of this procedure is found in the City of Lincoln, Nebraska, Water Treatment Plant Laboratory. Water treatment includes chlorination. When water is chlorinated, chlorine reacts with organic matter to form trihalomethanes (THMs), such as chloroform, bromoform, bromodichloromethane, and chlorod-ibromomethane. THMs in water are regulated by the Safe Drinking Water Act, and so the laboratory must analyze the treated water to determine their concentration. 

HI Maximum organic contaminant level Total trihalomethane (TTHM) (TTHM = the sum of the concentration of bromodichloromethane, dibromochloromethane and chloroform) Fresh water Salt water Fish consumption Acute 9,600 jjglL ns 5.1 Chronic ns ns ... 

Chu I, Villeneuve DC, Secours VE, et al. 1982a. Trihalomethanes II. Reversibility of toxicological changes produced by chloroform, bromodichloromethane, chlorodibromomethane and bromoform in rats. 

Eipsky MM, Skinner M, O Connell C. 1993. Effects of chloroform and bromodichloromethane on DNA synthesis in male F344 rat kidney. Environ Health Perspect 101(Suppl 5) 249-252. 

Munson AE, Sain LE, Sanders VM, et al. 1982. Toxicology of organic drinking water contaminants Trichloromethane, bromodichloromethane, dibromochloromethane and tribromomethane. Environ Health Perspect 46 117-126. 

Tumasonis CF, McMartin DN, Bush B. 1985. Lifetime toxicity of chloroform and bromodichloromethane when administered over a lifetime in rats. Ecotoxicol Environ Safety 9 233-240. 

Biological. Bromodichloromethane showed significant degradation with gradual adaptation in a static-culture flask-screening test (settled domestic wastewater inoculum) conducted at 25 °C. At concentrations of 5 and 10 mg/L, percent losses after 4 wk of incubation were 59 and 51, respectively. At a substrate concentration of 5 mg/L, 8% was lost due to volatilization after 10 d (Tabak et ah, 1981). 

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