Efficiency of the tablet chlorinator in the inactivation of pathogenic organisms in drinking water

A 5-year study was conducted to determine the vulnerability of Non-PRASA (not pertaining to the Puerto Rico Aqueduct and Sewer Authority) systems to waterborne pathogens and the efficiency of the calcium hypochlorite tablet chlorinator in the inactivation of these particular agents. Non-PRASA systems are small water supplies characterized by the low bacteriological quality of the drinking water served, representing a risk to public health. Several entities are making efforts to install disinfection treatment at these systems; as a result of this effort, 67% of Non-PRASA community systems provide disinfection to their drinking water. From this number, 78% of these systems that provide disinfection use the tablet chlorinator, making these communities an ideal area to determine the efficiency of this technology in the inactivation of organism indicators of microbiological contamination.; An evaluation of Non-PRASA systems to determine characteristics and needs was done through visits, phone calls and reviews of inspections and sanitary surveys. Over 8,000 microbiological results were evaluated to determine the vulnerability of these communities to waterborne pathogens. The Finca Geraldo Pagán system was chosen for a 10-day sampling to determine the efficiency of the tablet chlorinator in the inactivation of coliform bacteria. Inactivation of viruses and Giardia lamblia was also determined.; Two factors were considered as critical when determining the efficiency of the tablet chlorinator: the residual chlorine concentration and the perception of water quality. Over 90% of water samples obtained acceptable bacteriological results when the chlorine concentration was kept at or over 0.2 mg/L. The color, odor and taste of the water in these communities determine the perception of “how good” the water is. Cultural behavior and knowledge of drinking water issues influence also in the perception of water quality, which in turn, will be critical in determining if further treatment is needed and if a specific technology is applicable to a particular population.; This research determined that the calcium hypochlorite tablet chlorinator has the potential to be an effective disinfection agent at drinking water facilities located at the poorest areas where economic resources and knowledge of public health practices are limited.