title: [Preliminary survey to detect toxic substances in domestic potable water, Bogotá and Soacha, 2012].
abstract: BACKGROUND
  Significant alterations may be found in the water of Bogotá´s water supply system after its purification, specifically during its distribution and storage in home reservoirs, which makes it necessary to study the final quality of the domiciliary water consumed by users.
  
  
  OBJECTIVE
  To conduct a preliminary study of toxic chemical substances in the water supplied by Bogotá´s water supply system in samples obtained from residential reservoirs and faucets.
  
  
  METHODS
  Descriptive study made in 26 homes located in Bogotá and Soacha. Two samplings were done during different seasons, each including a survey and the collection of water samples from domiciliary storage tanks and faucets. Samples were analyzed for basic physicochemical parameters, a screening test for organic and inorganic substances and the determination of heavy metals and residues of organophosphate pesticides and/or carbamates.
  
  
  RESULTS
  Values obtained for conductivity, color and nitrates were acceptable, pH and turbidity were slightly high while residual chlorine levels were low; aluminum traces were found in 94% of the samples; 8% of the samples analyzed during the dry season showed organic compounds, compared to 66.7% during the rainy season, and just one positive result was obtained for inorganic compounds. Consequently, a medium risk level was observed in 11.5% of homes, low risk in 61.5% and no risk in 27.0%.
  
  
  CONCLUSIONS
  The evidence showed deterioration of the domiciliary water by organic substances present in the reservoirs as well as in the water supply piping, probably caused by the formation of biofilms or organic polymers. Aluminum levels close to the top permissible limit can be explained by the presence of residual coagulants used during water treatment.
authors.affiliation: Grupo de Salud Ambiental Jaime Eduardo Ortiz Varón, Dirección de Redes en Salud Pública, Instituto Nacional de Salud, Bogotá, D.C, Colombia.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Silva
authors.affiliation: Grupo de Salud Ambiental Jaime Eduardo Ortiz Varón, Dirección de Redes en Salud Pública, Instituto Nacional de Salud, Bogotá, D.C, Colombia.
authors.forename: María Elsa
authors.initials: ME
authors.lastname: Villarreal
authors.affiliation: Grupo de Salud Ambiental Jaime Eduardo Ortiz Varón, Dirección de Redes en Salud Pública, Instituto Nacional de Salud, Bogotá, D.C, Colombia.
authors.forename: Omayda
authors.initials: O
authors.lastname: Cárdenas
authors.affiliation: Grupo de Salud Ambiental Jaime Eduardo Ortiz Varón, Dirección de Redes en Salud Pública, Instituto Nacional de Salud, Bogotá, D.C, Colombia.
authors.forename: Carlos Armando
authors.initials: CA
authors.lastname: Cristancho
authors.affiliation: Grupo de Calidad del Agua, Dirección de Redes en Salud Pública, Instituto Nacional de Salud, Bogotá, D.C, Colombia.
authors.forename: Carmenza
authors.initials: C
authors.lastname: Murillo
authors.affiliation: Área de Ciencias Básicas, Corporación Unificada Nacional de Educación Superior, CUN, Bogotá, D.C, Colombia.
authors.forename: Manuel Alberto
authors.initials: MA
authors.lastname: Salgado
authors.affiliation: Grupo de Calidad del Agua, Dirección de Redes en Salud Pública, Instituto Nacional de Salud, Bogotá, D.C, Colombia.
authors.forename: Gerardo
authors.initials: G
authors.lastname: Nava
mesh_terms: D003105:Colombia; D060766:Drinking Water / Q000032:analysis*; D005191:Family Characteristics; D006801:Humans; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D060766:Drinking Water; D014874:Water Pollutants, Chemical