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The Sawyer PointONE™ hollow fiber membrane filter is increasingly promoted for long-term household water treatment in developing countries. Limited data demonstrate PointONE™ microbiological laboratory efficacy and short-term diarrheal disease reduction among users, but household microbiological data is lacking. To compare laboratory and household PointONE™ filter microbiological performance, we enumerated Escherichia coli (E. coli) and total coliforms in source and filtrate water from: (1) one new filter with E. coli-spiked water (107–109 CFU/100 mL) in the laboratory, (2) one new filter with natural Maine and Honduran surface waters, and (3) 50 filters used in Honduran homes for 1–3 years. In laboratory tests, all filtrate samples had <1 CFU/100 mL E. coli (>99.99999% reduction). In natural surface waters, all filtrate samples had ≤1 MPN/100 mL E. coli (≥99.5% reduction). In households, filtrate samples had geometric mean 5.1 MPN/100 mL E. coli (90% reduction), with only 30% of filtrate samples complying with international standards of undetectable E. coli. Total coliform presence in natural water filtrate varied for both new and household filters. The discrepancy between laboratory and household results and premature filter failure are not well understood. Further research is recommended to understand this performance disparity and determine filter failure mechanisms in households.

InterChemNet (ICN) is a Web-based management program designed to foster active learning in the laboratory. The system allows students choices of discovery-based experiments, a host of background information, and quick and easy access to UV–visible and FTIR spectrometers. The system creates individualized pathways for students by allowing instructors to present a hierarchy of lab choices and assignments in a given week. An evaluation module is integrated into the system to provide immediate feedback for students and evaluation data for instructors. Because assessment is integrated with curriculum delivery, ICN facilitates the introduction of chemical education research into existing courses based on local curricular goals. By making it easy for instructors to analyze learning outcomes for the course, ICN can be used to promote a systematic and evidence-based curriculum development cycle.

The Sawyer PointOne hollow fiber membrane microfilter is promoted for household water treatment in developing countries. Critical limitations of membrane filtration are reversible and irreversible membrane fouling, managed by backwashing and chemical cleaning, respectively. The PointOne advertised lifespan is 10 years; users are instructed to backwash as maintenance. Owing to reduced turbidity and bacterial removal efficiencies, six PointOnes were removed from Honduran homes after 23 months of use. In the laboratory, we tested sterile water filtrate for turbidity and bacterial presence before and after backwashing and chemical cleaning. Sterile water filtrate from uncleaned filters had turbidity of 144–200 NTU and bacteria counts of 13–200 CFU. Cleaned filter effluent was positive for total coliforms. On one new and one used, cleaned filter, we imaged membranes with scanning electron microscopy and characterized surface elemental compositions with spectroscopy. Images and spectroscopy of the used, cleaned membrane revealed a dense, cake fouling layer consisting of inorganic metal oxides, organic material, and biofouling. Burst fibers were visually observed. This PointOne was thus irreversibly fouled and non-functional after <2 years of use. Further research is recommended to determine: impacts of source water quality on PointOne performance, a cleaning regimen to manage fouling, and an appropriate filter lifespan.

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