HOUSEHOLD MEASURES FOR DISINFECTING WATER FOR HUMAN CONSUMPTION: ANALYSIS OF THE EFFECTS OF FILTRATION, BOILING AND USE OF SODIUM HYPOCHLORITE ON THE MICROBIOLOGICAL AND PARASITOLOGICAL CONTROL OF SPRING WATER IN COLATINA, ESPÍRITO SANTO

Abstract

This study aimed to determine the effectiveness of household water treatment methods—filtration through a porous ceramic filter (“clay filter”), boiling, and the addition of sodium hypochlorite—in reducing microbiological and parasitological contamination in water samples collected from natural springs used by the population of Colatina, Espírito Santo, Brazil. The samples were analyzed for physicochemical, microbiological, and parasitological parameters, with emphasis on the detection of total coliforms, including Escherichia coli, as well as the presence of oocysts. Filtration led to an increase in pH values in most of the analyzed samples, particularly in water from the Carlos Germano Naumann spring. With respect to apparent color, filtration had a limited effect, producing only slight reductions in specific cases. Notably, turbidity increased in some samples after filtration, such as those from the São Braz spring. The results demonstrated that both boiling and the addition of sodium hypochlorite were highly effective in eliminating total coliforms, Escherichia coli, and viable bacteria in culture. In contrast, clay filters proved ineffective in removing the microorganisms tested, with positive results for total coliforms, Escherichia coli, and bacteria including Gram-negative cocci and bacilli with morphologies consistent with potentially pathogenic Enterobacteriaceae. No intestinal parasitic forms were detected in any of the samples, regardless of treatment. These findings indicate that, while accessible and culturally widespread, the clay filter does not represent an effective microbiological barrier and may even allow for persistence or proliferation of bacteria following filtration. Conversely, boiling and chlorination with sodium hypochlorite are simple, low-cost, and highly efficient methods to ensure water potability in communities that rely on natural springs. The study highlights the importance of adopting complementary strategies and continuous monitoring of water quality to safeguard public health.