Aquatabs should be approved for point- of- use drinking water treatment in Haiti, for these reasons:

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1 Aquatabs Review and Recommendations Aquatabs are a point- of- use water treatment tablet manufactured by Medentech Ltd. in Wexford, Ireland. They are solid tablets composed of sodium dichloroisocyanurate (NaDCC). These tablets are sold in several sizes to treat various volumes of water. The product is marketed for treating water to prevent waterborne diseases in emergencies, defense and peacekeeping, travel, and household water treatment (1). Four samples of Aquatabs were purchased in the municipal market in Belladere, Haiti, in June Tufts University is assisting the Haitian MSPP by evaluating these samples and reviewing materials about the product. The types of Aquatabs evaluated are: - Two samples of 67 mg Aquatabs (for use with 20 L of water) - Two samples of 33 mg Aquatabs (for use with 4-5 L of water) Summary of Results Aquatabs should be approved for point- of- use drinking water treatment in Haiti, for these reasons: It is recognized by the US EPA, WHO, and NSF for use to treat drinking water at the point- of- use. The active chemical, NaDCC, has been shown to improve the microbiological quality of drinking water at the household level. The product can be easily measured, and it delivers a dose that is effective and safe for human consumption. The packaging provides adequate information and instructions for use. However, it is recommended that the product labeling be written in Kreyól, and that the 67 mg tablet size be promoted for use in Haiti. Independent Certifications The active ingredient of Aquatabs, NaDCC, is listed as complying with NSF / ANSI Standard 60, registered with the US Environmental Protection Agency (EPA), and is also listed as a possible water treatment method by the World Health Organization (WHO). NSF / ANSI Standard 60: Drinking Water Treatment Chemicals - Health Effects: Medentech has four products listed as complying with NSF / ANSI Standard 60 for use as a drinking water disinfectant at a dose of 10 mg/l: Aquatabs, Multipurpose Aquatabs, Waterguard Aquatabs, and Puritabs (2). This standard applies to chemicals used for drinking water treatment, and it certifies that the chemical is safe at the maximum dose, and that any impurities are below the maximum acceptable levels (3). This certification only applies to products that bear the NSF logo, which none of the 1

2 samples purchased in Haiti do. However, these Aquatabs would comply with the maximum dose if used properly. US Environmental Protection Agency (EPA) Registration: Aquatabs are registered with the US EPA (Registration # ) for routine drinking water treatment at the point of use. This product has been listed since 2011 (4). The manufacturer Occidental Chemical has had a similar NaDCC product registered for drinking water disinfection since 1996 (5). World Health Organization (WHO): The World Health Organization does not currently approve products for use to treat drinking water. However, the Guidelines for Drinking Water Quality lists NaDCC tablets as a point- of- use water treatment method commonly used to prevent diarrhea in developing countries and for travellers (6). Verification of Composition and Dosage Medentech manufactures Aquatabs ranging from 3.5 mg (to treat 1 liter) to 8.68 g (to treat 2,500 liters) per tablet. There are two types of tablets: tablets for every day use, and emergency tablets. Every day tablets are sized to deliver a dose of 2 mg/l free chlorine residual (FCR) for clear water, and emergency tablets deliver 4-6 mg/l FCR to dirty or fecally contaminated water (7). Each package of Aquatabs evaluated lists the tablet composition in mg of NaDCC. The Aquatabs evaluated are: Two packages of 33 mg Aquatabs to treat 4-5 liters of dirty/fecally- contaminated water. The final target chlorine concentration for these sample tablets is 4-5 mg/l FCR. Two packages of 67 mg Aquatabs to treat 20 liters of clear, every day water. The final target chlorine concentration for these sample tablets is 2 mg/l FCR (7). One tablet from each package was tested at Tufts University in Medford, MA, USA in September The tablet was mixed into a sample of clean, deionized water, and the FCR concentration was measured after 30 minutes with a LaMotte portable colorimeter. In these test results, the FCR concentration of water treated with non- expired Aquatabs differed from the target concentration by 0% to 6% (Table 1). One tested sample had expired, and this differed from the target FCR concentration by 10%. At the recommended dosages of 2.0 and 4.0 mg/l, the chlorine concentration in water treated with Aquatabs would all be below the World Health Organization (WHO) recommended limits for drinking water for free chlorine, which is 5.0 mg/l (6). The US EPA allowable limit for chlorine in drinking water is 4.0 mg/l (8). The recommended daily intake limit for the chemical dichloroisocyanuric acid is mg/kg of body weight. For a normal adult, this means the recommended NaDCC limit is 50 mg/l (6). Water treated with Aquatabs is far below this limit. 2

3 Sample Volume of Treated Water (L) Table 1: Aquatab Free Chlorine Residual Testing Target FCR Concentration, Treated Water (7) Tested FCR Concentration, Treated Water WHO Drinking Water Guidelines for FCR (6) 33 mg, Sample mg, Sample mg, Sample mg, Sample 2 (expired) While all Aquatabs should provide appropriate FCR doses if used correctly, users may be confused about the different tablet sizes available. It is recommended that the 67 mg tablet be primarily promoted for household drinking water treatment, as a 5- gallon (20 Liter) bucket is the most common water storage container in Haiti. With this volume of water, the 67 mg tablet provides a 2.0 mg/l dose of FCR. This is the dose recommended by the CDC for treating drinking water at the household level (9). In summary, the tested concentration of free chlorine is close to the expected concentration, and NaDCC and free chlorine concentrations are within safe recommended limits of human consumption for drinking water. The 67 mg Aquatab tablet is the preferred tablet for household water treatment use. Verification of Effectiveness When dissolved in water, NaDCC disinfects with free available chlorine in the form of hypochlorous acid (HOCl). Chlorination is known to be an effective at disinfecting drinking water, and it has been used in municipal systems all over the world since the early 1900s (10). There have been several studies showing that NaDCC is effective against E. coli, salmonella, total coliform, Vibrio cholerae, and viruses (11). There have also been studies of Aquatabs (NaDCC tablets) used in developing countries to disinfect stored household drinking water. These studies show that the Aquatabs are effective at improving the microbiological quality of drinking water at the household level (12, 13). Also, there is a growing body of evidence showing that chlorination at the household level is protective against endemic diarrhea. No studies using NaDCC have shown a significant disease reduction, but in these studies the water was clean to begin with, or not enough people used the tablets to show a reduction in disease. Further studies are needed to show the potential impact of Aquatabs in reducing disease. In summary, Aquatabs are effective at improving the microbiological quality of drinking water when used at the household level. Product Packaging and Labeling Aquatabs packaging is labeled in English, Spanish, and French. The package lists the product composition, dates of manufacture and expiration, volume of water to treat, and instructions for use. This package gives the correct information, but it should also be written in Kreyól. 3

4 Only the individually- packaged Aquatab packaging was evaluated here. Medentech also sells Aquatabs in bottles, but this packaging was not evaluated. There are also Aquatabs manufactured specifically for use in Haiti with Kreyól labeling, but these products were not evaluated. Recommendations The use and promotion of this product for household water treatment should be approved in Haiti. However, it is recommended that the manufacturer provide a package labeled in Kreyól. There are different sizes of Aquatabs available, but the 67 mg Aquatab tablet is recommended for use with a standard size 5 gallon (20 L) bucket of water in Haiti. 4

5 References (1) Aquatabs, Medentech Ltd. (2) NSF Product and Service Listings, Medentech Limited. (3) NSF / ANSI Standard 60 (4) United States Environmental Protection Agency Pesticide Product Label System, Aquatabs. (5) United States Environmental Protection Agency Pesticide Product Label System, ACL 60 EUP Chlorinating Granules. 2, (6) WHO Guidelines for drinking water quality. 4th ed. Geneva: World Health Organization, (7) Aquatabs Technical Report. Wexford, Ireland: Medentech Ltd., (8) United States Environmental Protection Agency Primary Drinking Water Regulations, (9) Centers for Disease Control and Prevention Chlorine Residual Testing Fact Sheet. (10) Black & Veatch Corporation, White s Handbook of Chlorination and Alternative Disinfectants, 5th ed. John Wiley & Sons, Inc., Hoboken, NJ, USA. (11) Clasen, Thomas, and Paul Edmondson Sodium dichloroisocyanurate (NaDCC) tablets as an alternative to sodium hypochlorite for the routine treatment of drinking water at the household level. International journal of hygiene and environmental health 209(2): (12) Jain, Seema, Osman K Sahanoon, Elizabeth Blanton, Ann Schmitz, Kathleen A Wannemuehler, Robert M Hoekstra, and Robert E Quick Sodium dichloroisocyanurate tablets for routine treatment of household drinking water in periurban Ghana: a randomized controlled trial. The American journal of tropical medicine and hygiene 82(1): =abstract. (13) Clasen, Thomas, Tanveer F Saeed, Sophie Boisson, Paul Edmondson, and Oleg Shipin Household water treatment using sodium dichloroisocyanurate (NaDCC) tablets: a randomized, controlled trial to assess microbiological effectiveness in Bangladesh. The American journal of tropical medicine and hygiene 76(1):