Storage tanks for household water usage in Brazil: Microbiological and chemical quality, and maintenance of sanitary conditions

Abstract

Introduction: Storage tanks for household water usage guarantees convenience and safety forconsumers in relation to water intermittency. Neglecting a minimal care for storage tanks can turnthem into a source of water unfit for consumption. Objective: Evaluate the physical, chemical, andmicrobiological quality of water in household tanks to highlight the need for individual actions toguarantee the quality of water consumed at home. Methods: Residents of 217 homes answereda questionnaire to gather information about the water storage tank conditions and maintenance.Chlorine dosing, pH and temperature measurements were performed in situ and metal analyseswere made using an inductively coupled plasma mass spectrometry (ICP-MS). The presence ofparasites was evaluated using the spontaneous sedimentation technique and presence of bacteriafrom the coliform groups (total and fecal) were made using the multiple-tube technique with thechromogenic substrate. Results: Results showed that 115 participants knew the correct storage tankmaintenance period and 109 participants did not perform the storage tank maintenance at therecommended frequency. Mean values of chlorine, pH, and temperature were 1.34 mg/L, 6.5, and25.4 ºC, respectively. Average concentrations of metals were below the maximum values allowed.Parasites and bacteria were not detected. Tests indicated the water samples were in accordancewith the potable water quality standards endorsed or recommended by the Brazilian legislation.Conclusion: Results did not show microbiological contamination in study samples. Nevertheless, it isnecessary to keep the population regularly informed about the importance to maintain storage watertanks clean. Currently, there is a growing concern with the development of individual actions aimedat human health and prevention of water-related diseases concerning its access and use. Therefore,we need health education programs to guide community participation into the promotion of a betterquality of life.