title: [Measurement of drinking water contaminants and water use activities during pregnancy in a cohort study in Spain].
abstract: OBJECTIVE
  Exposure to chlorination by-products during pregnancy has been associated with reproductive outcomes but the evidence remains inconclusive. Levels of trihalomethanes, the most prevalent chlorination by-products, are high in some areas of Spain. Within the framework of a follow-up study in pregnant women, we describe: 1) the personal habits of water use and consumption, and 2) trihalomethane levels in the drinking water of the study areas.
  
  
  METHODS
  We performed a follow-up cohort study in pregnant women in Valencia (n = 800), Sabadell (n = 800), the Basque Country (n = 600), Asturias (n = 500), and Granada (n = 700). Interviews were conducted in the third trimester of pregnancy to obtain individual information on the sources and amounts of drinking water, and on the frequency of showering, bathing, and swimming pool attendance. Water samples were collected to analyze trihalomethane levels.
  
  
  RESULTS
  The main source of drinking water was bottled water, both inside and outside the home (82% and 94% of the women, respectively). Drinking water for cooking was mainly municipal (91%). Women preferred to take showers (98.2%) and did so, on average, 6.8 times/week for 11.7 minutes. A total of 58.5% of the women went to swimming pools during pregnancy, on average 9.4 times/month to outdoor swimming pools in the summer and 3.1 times/month the rest of the year for 32.6 and 21.7 minutes, respectively. Average trihalomethane levels ranged from 4 microg/l in the province of Granada to 117 microg/l in Sabadell.
  
  
  CONCLUSIONS
  These preliminary results suggest that the main routes of trihalomethane exposure during pregnancy are dermal absorption and inhalation. Ingestion is a minor exposure route.
authors: Centre de Recerca en Epidemiologia Ambiental (CREAL), Institut Municipal d'Investigació Mèdica (IMIM), Barcelona, España. cvillanueva@imim.es
authors: Cristina M
authors: CM
authors: Villanueva
authors: Joan O
authors: JO
authors: Grimalt
authors: Ferran
authors: F
authors: Ballester
authors: Jesús
authors: J
authors: Ibarluzea
authors: Maria
authors: M
authors: Sala
authors: Adonina
authors: A
authors: Tardón
authors: Elena
authors: E
authors: Romero-Aliaga
authors: Marieta
authors: M
authors: Fernández
authors: Núria
authors: N
authors: Ribas-Fitó
authors: Manolis
authors: M
authors: Kogevinas
mesh_terms: D002675:Child, Preschool; D015331:Cohort Studies; D004326:Drinking; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D011247:Pregnancy; D013030:Spain; D022882:Trihalomethanes / Q000032:analysis*; D014877:Water Pollution, Chemical / Q000032:analysis*
chemical_list: D022882:Trihalomethanes