Toxicology of organic drinking water contaminants: trichloromethane, bromodichloromethane, dibromochloromethane and tribromomethane.

Abstract

This study evaluated the subchronic toxicity of selected halomethanes which are drinking water contaminants. The compounds studied were trichloromethane, bromodichloromethane, dibromochloromethane and tribromomethane. Subchronic 14-day gavage studies were performed with the use of doses encompassing one-tenth the LD50 for the compounds. A 90-day gavage study of one of the compounds, trichloromethane, was also done. Parameters observed included body and organ weights, histopathology, hematology, clinical chemistries, and hepatic microsomal enzyme activities. Toxicity to the humoral immune system was assessed by measuring the number of splenic IgM antibody-forming cells and the serum antibody level to sheep erythrocytes. Cell-mediated immunity was evaluated by measuring the delayed type hypersensitivity response and popliteal lymph node proliferation response to sheep red blood cells. The functional activity of the reticuloendothelial system, as measured by the vascular clearance rate and tissue uptake of 51Cr sheep red blood cells was also determined.The major effects of the halomethanes were increased liver weights, elevations of SGPT and SGOT, decreased spleen weights and a decrease in the number of splenic IgM antibody-forming cells. The humoral immune system appeared to be an indicator of halomethane toxicity. There is evidence that subchronic 14-day exposure may be of greater value than long-term studies in determining the toxicity of these compounds.

Association of blood trihalomethane concentrations with asthma in US adolescents: nationally representative cross-sectional study

“…Most mechanistic studies suggest that THMs may increase asthma risk by inducing perturbations of the immune system. In animal studies, Munson and colleagues reported depressed humoral and cellular immunity in mice after administration of BDCM or DBCM [26]. Auttachoatet and colleagues observed decreased numbers of blood circulating neutrophils in female B6C3F1 mice when TCM exposure occurred via drinking water [27].…”

Acute changes in serum immune markers due to swimming in a chlorinated pool

“…Evidence from a handful of animal studies points towards an immunosuppressive effect of DBPs in drinking water. Munson et al (1982) reported immunosuppression in mice after administration of BDCM or DBCM ; Exon et al (1987) reported immunosuppression in rats after high doses to chlorinebased disinfectants, Ueno et al (1999) reported suppression of immune responses in mice after exposure to chlorinated humic acid-concentrate as a mixture of chlorination by-products, and Auttachoat et al (2009) observed a decreased number of circulating neutrophils in blood of mice exposed to chloroform, though neutrophil function in lung homogenates was not compromised. French et al (1999) found no effects of BDCM on the immune function of mice and rats after exposure through drinking water and oral gavage.…”

“…Evidence for potential immunotoxic effects of DBPs is available from a handful of animal studies (Auttachoat et al, 2009;French et al, 1999;Munson et al, 1982), while studies among humans exposed to halocarbons that are structurally very similar to DBPs also provide evidence for immunotoxic effects (Bassig et al, 2013;Griffin et al, 2000;Iavicoli et al, 2005;Weber et al, 2003).…”

On Determination of Reference Chloroform Content in Children's Blood

“…Munsonetal. (1982) [14] detected in their research that chlorinated organic compounds (chloroform, tetrachloromethane, BDCM, and others) exert adverse impacts on the digestive organs, urinary excretion organs, the circulatory, nervous, and hormonal systems under oral exposure. Some COCs are carcinogenic [15][16][17][18][19].…”