Metabolism and pharmacokinetics of alternate drinking water disinfectants.

Abstract

The chlorination of surface waters is known to elevate trihalomethanes; consequently, chlorine dioxide (CI02) is being considered as an alternative disinfectant. The primary products resulting from C102 disinfection of waters are chlorites (CIO2-) and chlorates (C103-). Studies in rats revealed that C102 is converted to chloride (ClI), CIO2-and CIO3-. C1O2-and CIO3-are excreted as Cl1, C102-and Cl-, C102-, Cl03-, respectively. Radioactivity was rapidly absorbed from the gastrointestinal tract following the administration of 'CIO2 orally, and the half-life for the elimination of 3Cl from the rat was 44 hr, corresponding to a rate constant of 0.016/hr. After 72 hr, radioactivity was highest in plasma, followed by kidney, lung, and stomach. 36CI in plasma reached a peak at 2 hr and 1 hr after oral administration of 36C102-and 36CI03-, respectively. 3Cl excretion was greatest 24 hr after the administration of 36CI03-, but in the case of 'CI02-, the excretion probably represented saturation of the biotransformation and excretion pathway. A low activity in packed cells compared to plasma was detected in chlorate ingestion, rather than an even distribution in chlorite treatment. Chloroform determinations in rat blood after one year indicated that chloroform was significantly higher than control in the 100 and 1000 mg/l. C102 groups. However, no significant values were observed in the 1 or 10 mg/I. C102 and C102 metabolites group. C102 and its metabolites are eliminated from the body more rapidly than chlorine, and they do not appear to increase trihalomethane concentrations at low dosages.

Tissue Distribution, Elimination, and Metabolism of Dietary Sodium [36Cl]Chlorate in Beef Cattle

“…In cattle, the vast majority of urinary radioactivity was chlorate with little chloride and no chlorite being present. The doses of chlorate administered to cattle in this study were much greater than the dose administered to rats (0.15 mg/kg body weight) by Abdel-Rahman et al (15). In addition, their data were collected over a withdrawal period of 72 h after a single administration, whereas data in this study were collected after three doses and only an 8 h withdrawal period.…”

“…Furthermore, the safety of chlorate residues in edible tissues of cattle has not been demonstrated. In rodents, chlorate appears to be rapidly absorbed and excreted (15) and chlorate is apparently metabolized to chlorite and chloride ions. The overall goal of this study was to determine if further development of chlorate as a commercial product was warranted from the perspective of the magnitude of residues in edible tissues.…”

Pharmacokinetics of ruminally dosed sodium [36Cl]chlorate in beef cattle

“…, 1978; Steffen & Seitz, 1981; Eysseric et al. , 2000), there is scant literature in which any pharmacokinetic parameters were measured (Abdel‐Rahman et al. , 1982, 1985; Steffen & Wetzel, 1993).…”

Sodium chlorite increases production of reactive oxygen species that impair the antioxidant system and cause morphological changes in human erythrocytes

“…Ingested chlorite is rapidly absorbed through the gastrointestinal tract and enters the blood stream where it interacts with erythrocytes. Abdel‐Rahman et al () have reported that after ingestion, the highest concentrations of chlorite were found in the blood and stomach. We have used human erythrocytes as an experimental model in our study of chlorite toxicity, especially on the antioxidant system.…”

“…When inhaled, dusts or mists of NaClO 2 cause irritation of the mucous membrane and respiratory tract. After ingestion, chlorite is distributed throughout the body with the highest concentrations being found in the blood, stomach, testes, skin, lung, kidneys, small intestine, spleen, brain, bone marrow, and liver (Abdel‐Rahman et al, ). The major adverse health effects of NaClO 2 exposure in humans are methemoglobinemia, severe oxidative hemolysis, disseminated intravascular coagulation, and anuric acute kidney injury (Romanovsky et al, ).…”