1996 Ward Chloramine Removal From Water Used in Hemodialiysis Several outbreaks of hemolysis in hemodialysis patients have occured when chloramines in the public water supply have not been adequately removed by the dialysis unit's water purification system. Chloramines are not removed by reverse osmosis or deionization, and need to be either adsorbed by filtration through granular activated carbon (GAC) or neutralized by chemical reduction by ascorbic acid (vitamin C) added to the dialysate. 1998 Peterka Vitamin C: A Promising Dechlorination Reagent This article discusses the use of vitamin C to neutralize the toxic effects of chlorine on aquatic life. Vitamin C neutralizes both chlorine and chloramines. Because it is a mild acid, lowered pH values are not a major issue. Oxygen levels normally remain unchanged during the dechlorination process. While eliminating chlorine harmful to fish, the excess vitamin C provides some protection against diseases by enhancing fish immune systems. Using vitamin C could someday replace the use of sulphur-based compounds. Proper dosage, wastewater treatment potential, and dechlorination at the hydrant are discussed. 1999 Perez-Garcia Chloramine, a sneaky contaminant of dialysate Chloramines have a low molecular weight, are neutral, and can pass through semipermeable membranes including those of reverse osmosis. They are not trapped by decalcifying or deionizing columns. Consequently, special treatment is necessary for their elimination or neutralization [7,8]. There are three approaches to eliminate chloramines and to prepare water for haemodialysis: (i) activated charcoal; (ii) sodium bisulfite; and (iii) ascorbic acid. 2001 Tikkanen Guidance Manual for Disposal of Chlorinated Water By Maria Tikkanen More than you would ever want to know about chlorine and chloramiune in water and how to remove it. 2001 Vissers Regulation of Apoptosis by Vitamin C We have investigated the ability of intracellular vitamin C to protect human umbilical vein endothelial cells from exposure to hypochlorous acid (HOCl) and a range of derived chloramines. Ascorbate provided minimal protection against the cytotoxicity induced by these oxidants, as measured by propidium iodide uptake. In contrast, there was a marked effect on apoptosis, monitored by caspase-3 activation and phosphatidylserine exposure. Extended incubation of the cells with glycine chloramine or histamine chloramine completely blocked apoptosis initiated in the cells by serum withdrawal. This effect was significantly abrogated by ascorbate. Inhibition of apoptosis required the oxidant to be present for an extended period after serum withdrawal and occurred prior to caspase-3 activation. General protection of thiols by ascorbate was not responsible for the protection of apoptosis, because intracellular oxidation by HOCl or chloramines was not prevented in supplemented cells. The results suggest a new role for vitamin C in the regulation of apoptosis. We propose that, by protection of an oxidant-sensitive step in the initiation phase, ascorbate allows apoptosis to proceed in endothelial cells under sustained oxidative stress. (A-pop-TOH-sis) A type of cell death in which a series of molecular steps in a cell lead to its death. This is one method the body uses to get rid of unneeded or abnormal cells. The process of apoptosis may be blocked in cancer cells. Also called programmed cell death.

2005 Land Using Vitamin C To Neutralize Chlorine in Water Systems Operators of seasonal water systems sanitize spring-boxes or wells, storage tanks (figure 1), and distribution lines with a strong chlorine solution. After these operators sanitize the water systems, they must waste the chlorinated water. Chlorine can kill fish and other aquatic organisms. Therefore, operators must neutralize the chlorinated water before discharging the water into lakes or streams. The chlorinated water needs neutralizing if the wasted water goes to a septic system or small wastewater treatment plant, because chlorine can upset the bacterial balance in the system. Even very low levels of chlorine will harm or destroy aquatic organisms and beneficial bacteria. Operators need a permit from their State regulatory agency before discharging any treated or altered water to navigable waters of the United States or into a publicly owned wastewater treatment plant. 2009 Kunes Vitamin C attenuates hypochlorite-mediated loss of paraoxonase-1 activity from human plasma Paraoxonase 1 (PON1) is a cardioprotective enzyme associated with high-density lipoprotein (HDL). We tested the hypothesis that vitamin C protects HDL and PON1 from deleterious effects of hypochlorous acid, a proinflammatory oxidant. In our experiments, HDL (from human plasma) or diluted human plasma was incubated with hypochlorite in either the absence (control) or presence of vitamin C before measuring chemical modification and PON1 activities. Vitamin C minimized chemical modification of HDL, as assessed by lysine modification and accumulation of chloramines. In the absence of vitamin C, chloramines accumulated to 114 ± 4 μmol/L in HDL incubated with a 200-fold molar excess of hypochlorite; but addition of vitamin C (200 μmol/L) limited formation to 36 ± 6 μmol/L (P < .001). Our results lead to several important conclusions. First, it is clear that vitamin C protects HDL from hypochlorite-mediated chemical modification (ie, chlorination). 2010 Basu Potential Aquatic Health Impacts of Selected Dechlorination Chemicals Municipal wastewater effl uents are one of the largest single effl uent discharges in Canada. Chlorination of wastewater effl uents is a widespread practice throughout Canada (excluding Quebec), the United States and parts of Europe. As chlorine in wastewater effl uents is toxic to aquatic biota, dechlorination chemicals may be used to reduce residual chlorine concentrations to below 0.02 mg/L (as Cl2 ) as mandated by Canadian law. However, the potential aquatic health impacts of residual dechlorination chemicals must also be determined. Seven dechlorination agents (ascorbic acid, hydrogen peroxide, calcium thiosulfate, sodium sulfi te, sodium thiosulfate, sodium metabisulfi te, sodium bisulfi te) were evaluated with regards to their 48 hour acute toxicity. Tests were conducted using Daphnia magna to identify the acute (48 h) toxicity affects of the dechlorination chemicals over a range of concentrations (0–200 mg/L). Sodium sulfi te and thiosulfate were found to have the least aquatic mortality effects while hydrogen peroxide and calcium thiosulfate had the most deleterious effects. AA follows a similar profile to that observed for SMBS and SS, although the AA appears to be slightly less lethal than either of the other two DA at 200 mg/L with 13% survival versus 0% survival at this concentration. This may be attributed to the indirect toxicity associated with the solution pH change with AA, as opposed to the direct toxicity at this concentration for SS and SMBS. CTS and HP are the most toxic dechlorination agents tested in this study. Percentage survival under CTS and HP is significantly below all of the other chemicals tested (Fig. 2 to 4). For both of these chemicals, the percentage survival values start decreasing at concentrations as low as 2 mg/L. At 20 mg/L, HP caused 100% mortality in all the replicates tested. At 100 mg/L, CTS caused 100% mortality in all replicates tested. As neither the HP nor CTS resulted in an appreciable change in the DO or solution pH, both are likely directly toxic to the D. magna. The LC50 values for each of the chemicals are shown in Table 6. The 48 h LC50 values were determined using the Graphical Method (US EPA 2002) and an example of this method is shown in Figure 5. STS and SS could not be analyzed because the graphical method used is only valid for analyzing data when the obtained percentage mortalities bracket the 50% mortality mark. 2011 Basu Comparison of dechlorination rates and water quality impacts for sodium bisulfite, sodium thiosulfate and ascorbic acid The impact of water quality parameters such as organic and inorganic matter as well as chlorine species (free chlorine and monochloramine) on the rate of dechlorination by sodium bisulfite (SBS), sodium thiosulfate (STS) and ascorbic acid (AA) were studied. Reaction rate constants determined for the various dechlorination reactions showed that SBS and AA achieved dechlorination at a faster rate than STS. Organic matter present in the test solution increased the rate of dechlorination by STS but not SBS and AA. AA was found to be ineffective for the removal of monochloramine. The effect of dechlorination chemicals on water quality with respect to pH, turbidity and total organic carbon (TOC) was investigated along with the acute toxicity of the chemicals on the aquatic indicator species Daphnia magna. SBS was determined to have an LC50 of 68 mg/L with no toxicity impacts observed when the concentration was ≤ 20 mg/L for D. magna. AA increased the TOC levels in the treated water and resulted in some D. magna mortality at higher levels. STS had the least impact on daphnia mortality rates, but the use of STS for dechlorination resulted in the largest pH change of test waters compared to the other dechlorination chemicals. Editors note: Ascorbic acid does remove chloramine, their tests were wrong. As explained in 2013_Lioqing, there is a rebound effect and you have to use a larger amount of ascorbic acid and then it will remove it. - rjs 2013 Lioqing Removal of Chlorine Residual in Tap Water by Boiling or Adding Ascorbic Acid The quickest way to reduce the concentration of free chlorine in tap water is to add powdered vitamin C (ascorbic acid) tablets. At a ratio of 1:1.00, free chlorine was completely eliminated by ascorbic acid in less than 1 min. For tap water containing 4 mg/L of free chlorine as Cl2, which is the maximum concentration in the United States [7], it was determined that 10 mg of ascorbic acid is required to treat 1 L of tap water. A common vitamin C tablet weighs 500 mg and is commercially available in bottles of 300 for US $21. Potentially, this is enough to treat 15 m3 of tap water. Ascorbic acid added in a molar ratio of 1:1 (free chlorine to ascorbic acid) completely eliminated free chlorine. The DPD indicator did not produce a red color when added within 1 min after the addition of ascorbic acid. Reduction of free chlorine by ascorbic acid (from Bedner et al., 2004) can be expressed as follows: C6H8O6 + HOCl → C6H6O6 + HCl + H2O . Ascorbic acid (C6H8O6) is oxidized to dehydroascorbic acid (C6H6O6). Simultaneously, free chlorine (HOCl) is reduced to chloride ions (HCl). The reduction of monochloramine by ascorbic acid can be expressed as: C6H8O6 + NH2Cl ⇌ C6H6O6 + NH4Cl Ascorbic acid (C6H8O6) is oxidized to dehydroascorbic acid (C6H6O6). Simultaneously, monochloramine (NH2Cl) is reduced to ammonium chloride (NH4Cl). Monochloramine is more difficult to treat. A 44-min boiling was required to eliminate 3.33 mg/L of monochloramine. The concentration of monochloramine did not rebound. A molar ratio of 1:2.50 monochloramine to ascorbic acid was required to eliminate monochloramine as well as inhibit its reformation. For tap water containing 4 mg/L of monochloramine as Cl2, which is the maximum concentration in the United States, it was determined that 25 mg of ascorbic acid is required to treat 1 L of tap water. The same bottle of vitamin C tablets treats 6 m 3 of tap water. In comparison to boiling tap water, adding ascorbic acid to tap water is still quicker, requiring less than 2 min to eliminate 4 mg/L of monochloramine.