title: Nitrate and trace elements in municipal and bottled water in Spain.
abstract: OBJECTIVE
  To describe levels of nitrate and trace elements in drinking water from the study areas of a multicase-control study of cancer in Spain (MCC-Spain).
  
  
  METHODS
  A total of 227 tap water samples were randomly collected from 67 municipalities in 11 provinces and the nine most frequently consumed bottled water brands were sampled to measure levels of nitrate, arsenic, nickel, chromium, cadmium, lead, selenium and zinc.
  
  
  RESULTS
  The median nitrate level was 4.2mg/l (range<1-29.0), with similar levels in rural and urban municipalities (p=0.86). Trace elements were unquantifiable in 94% of tap water samples. Differences between areas were significant for nitrate (p<0.001) and arsenic (p=0.03). Only nitrate was quantifiable in bottled water (range 2.3-15.6mg/l).
  
  
  CONCLUSIONS
  Nitrate levels in municipal water differed between regions and were below the regulatory limit in all samples, including bottled water. Trace element levels were low and mainly unquantifiable in tap and bottled water.
authors.affiliation: Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain.
authors.forename: Nadia
authors.initials: N
authors.lastname: Espejo-Herrera
authors.forename: Manolis
authors.initials: M
authors.lastname: Kogevinas
authors.forename: Gemma
authors.initials: G
authors.lastname: Castaño-Vinyals
authors.forename: Nuria
authors.initials: N
authors.lastname: Aragonés
authors.forename: Elena
authors.initials: E
authors.lastname: Boldo
authors.forename: Eva
authors.initials: E
authors.lastname: Ardanaz
authors.forename: Lourdes
authors.initials: L
authors.lastname: Azpiroz
authors.forename: Enrique
authors.initials: E
authors.lastname: Ulibarrena
authors.forename: Adonina
authors.initials: A
authors.lastname: Tardón
authors.forename: Antonio J
authors.initials: AJ
authors.lastname: Molina
authors.forename: Concepción
authors.initials: C
authors.lastname: López-Rojo
authors.forename: José J
authors.initials: JJ
authors.lastname: Jiménez-Moleón
authors.forename: Rocío
authors.initials: R
authors.lastname: Capelo
authors.forename: Inés
authors.initials: I
authors.lastname: Gómez-Acebo
authors.forename: Mónica
authors.initials: M
authors.lastname: Ripoll
authors.forename: Cristina M
authors.initials: CM
authors.lastname: Villanueva
mesh_terms: D060766:Drinking Water / Q000737:chemistry*; D009566:Nitrates / Q000032:analysis*; D013030:Spain; D014131:Trace Elements / Q000032:analysis*
chemical_list: D060766:Drinking Water; D009566:Nitrates; D014131:Trace Elements