Samples were stratified at two different turbidity breakpoints, at <5 and ≥5 NTU and at <10 and ≥10 NTU, based on the discrepancy between recommendations of 5 or 10 NTU in WHO guidelines (WHO 2011). Each water quality parameter was the continuous, non-parametric variable with the source improvement category as the independent group variable. The American Journal of Tropical Medicine and Hygiene. The good thing is that the decline is predictable if environmental factors are controlled. Point‐of‐use (POU) water treatment with sodium hypochlorite (NaOCl) has been proven to reduce diarrheal disease in developing countries. That translates to 12% by weight available chlorine content. The outcomes analyzed were: (1) if FCR was ≤2.0 mg/L 1 hour and ≥0.2 mg/L 24 hours after chlorine addition; and (2) if FCR was ≤4.0 mg/L at 1 hour and ≥0.2 mg/L 24 hours after chlorine addition. Chlorination effects on DNA based characterization of water microbiomes and implications for the interpretation of data from disinfected systems. Oxidation reactions are corrosive, and solutions burn skin. Using a dose of 1.88 mg/L in improved water sources with turbidities of <5 or <10, the 0.2–2.0 FCR criteria were met 91–94% of the time at 8 hours and 82–87% at 24 hours (Table 5). Of note, studies using lower doses of chlorine have not documented these same reductions (LeChevallier et al. A binary stepwise logistic regression was performed to understand which factors were most significant in predicting whether or not a water sample would have a FCR ≥0.2 mg/L at 8 hours and at 24 hours. We conducted laboratory and field studies to further investigate the relationship between turbidity and chlorination efficacy to inform HWT with chlorination recommendations. 2008, 2010), there is still significant concern regarding the potential risk from THMs and other DBPs in chlorinating turbid water. While the WHO Evaluation Scheme for HWT products currently only considers laboratory efficacy, HWT products are used in real-world circumstances, and effectiveness in actual use in households is likely to be lower than laboratory efficacy. From 2003 to 2011, the authors completed or assisted with the water quality testing, product development, government approval processes, and training necessary to begin large-scale chlorination programs in 22 countries, including chlorine demand testing. Household chlorination is a common HWT method, and chlorination programs generally include three elements: water treatment with sodium hypochlorite or sodium dichloroisocyanurate at the household level; storage of chlorinated water in a safe container; and behavior change communication to improve hygiene and water and food handling practices (Lantagne et al. Sources meeting FCR criteria at two different doses and time points, stratified by source type and turbidity breakpoints. Sodium hypochlorite (NaOCl) is a compound that can be effectively used for water purification. doi: https://doi.org/10.2166/wh.2017.012. Sodium hypochlorite solutions were purchased locally in each country, and their concentrations were measured using Hach digital iodimetric titration Method 8209 (Loveland, CO). 2010). Further research on field effectiveness of chlorination is recommended. Suicide attempts in adults have shown that a lethal dose of sodium hypochlorite varies widely, with lethal results at 200-500 mL of 3-12% strength. To compare <5 and <10 NTU cutoffs and the percentage meeting FCR criteria, the 95% confidence intervals were calculated and compared. Five to ten minutes after spiking, reactors were dosed with 3.75 mg/L sodium hypochlorite using Clorox® bleach, the concentration of which was confirmed daily using Hach digital iodimetric titration Method 8209 (Loveland, CO). Learn more. Using breakpoints of unimproved water, water with ≥5 NTU turbidity, and unimproved water with ≥10 NTU turbidity all led to a similar percent of samples that met criteria. There was no E. coli reduction in the control reactors and the E. coli counts remained greater than 2.4 × 108CFU/100 mL for all reactors except for one, which was too numerous to count for all four time points. To disinfect it for drinking and also for other applications time at hours... 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