title: Risk of dying of cancer in the vicinity of multiple pollutant sources associated with the metal industry.
abstract: BACKGROUND
  Population exposure to emissions from multiple industrial sources, though little studied, is an aspect of great interest from an epidemiologic standpoint.
  
  
  OBJECTIVE
  To investigate whether risk of dying due to tumors of the digestive system in populations residing in the vicinity of Spanish metal production and processing installations increases with proximity to a greater number of industrial facilities.
  
  
  METHODS
  An ecologic study was designed to ascertain municipal mortality due to malignant tumors of the digestive system (oral cavity and pharynx, esophagus, stomach, pancreas, liver, gallbladder and colon-rectum) during the period 1994-2003, in Spanish regions with the presence of multiple industrial sources in the metal sector. Population exposure to pollution was estimated on the basis of distance from town of residence to pollution source. Using Poisson regression models, we analyzed: the increased risk of dying of cancer with proximity to a given number of sources; and excess mortality in the vicinity of specific industrial clusters.
  
  
  RESULTS
  The tumor responsible for the greatest number of regions with increased risk in both sexes was liver cancer (78% of the regions, being statistically significant in Valencia (p-value for trend (p trend)=0.001 in both sexes), Madrid (p trend=0.011 in women) and the Basque Country (p trend=0.002 in men)), followed by colorectal and pancreatic cancers (56% of the regions, being statistically significant in both sexes in Valencia (p trend=0.001) and Zaragoza (p trend=0.018) for colorectal cancer; and Valladolid (p trend=0.019 in men) and Barcelona (p trend=0.049 in women) for pancreatic cancer). Valencia was the province that displayed increased risk with the proximity to metal industries for all tumors studied, while the Basque Country was the Autonomous Region that registered a rising risk trend for liver, stomach and colorectal tumors with proximity (≤5 km) to a greater number of sources.
  
  
  CONCLUSIONS
  The results could support the hypothesis that mortality due to certain tumors of the digestive system increases with proximity (≤5 km) to a greater number of metal industry sources. Nevertheless, in this type of ecologic study, conclusions cannot be obtained in terms of cause and effect, nor can individual inferences be made from grouped data.
authors.affiliation: Cancer and Environmental Epidemiology Unit, National Center for Epidemiology, Carlos III Institute of Health, Avda. Monforte de Lemos, 5, 28029 Madrid, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Spain. Electronic address: jgarcia@isciii.es.
authors.forename: Javier
authors.initials: J
authors.lastname: García-Pérez
authors.affiliation: Cancer and Environmental Epidemiology Unit, National Center for Epidemiology, Carlos III Institute of Health, Avda. Monforte de Lemos, 5, 28029 Madrid, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Spain; Molecular Epidemiology of Cancer Unit, University Institute of Oncology, University of Oviedo, C/Fernando Bongera, s/n, 33006 Oviedo, Spain. Electronic address: flcina@isciii.es.
authors.forename: María Felicitas
authors.initials: MF
authors.lastname: López-Cima
authors.affiliation: Cancer and Environmental Epidemiology Unit, National Center for Epidemiology, Carlos III Institute of Health, Avda. Monforte de Lemos, 5, 28029 Madrid, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Spain. Electronic address: mpollan@isciii.es.
authors.forename: Marina
authors.initials: M
authors.lastname: Pollán
authors.affiliation: Cancer and Environmental Epidemiology Unit, National Center for Epidemiology, Carlos III Institute of Health, Avda. Monforte de Lemos, 5, 28029 Madrid, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Spain. Electronic address: bperez@isciii.es.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Pérez-Gómez
authors.affiliation: Cancer and Environmental Epidemiology Unit, National Center for Epidemiology, Carlos III Institute of Health, Avda. Monforte de Lemos, 5, 28029 Madrid, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Spain. Electronic address: naragones@isciii.es.
authors.forename: Nuria
authors.initials: N
authors.lastname: Aragonés
authors.affiliation: Cancer and Environmental Epidemiology Unit, National Center for Epidemiology, Carlos III Institute of Health, Avda. Monforte de Lemos, 5, 28029 Madrid, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Spain. Electronic address: pfernandezn@isciii.es.
authors.forename: Pablo
authors.initials: P
authors.lastname: Fernández-Navarro
authors.affiliation: Cancer and Environmental Epidemiology Unit, National Center for Epidemiology, Carlos III Institute of Health, Avda. Monforte de Lemos, 5, 28029 Madrid, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Spain. Electronic address: rramis@isciii.es.
authors.forename: Rebeca
authors.initials: R
authors.lastname: Ramis
authors.affiliation: Cancer and Environmental Epidemiology Unit, National Center for Epidemiology, Carlos III Institute of Health, Avda. Monforte de Lemos, 5, 28029 Madrid, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Spain. Electronic address: glabente@isciii.es.
authors.forename: Gonzalo
authors.initials: G
authors.lastname: López-Abente
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D004067:Digestive System Neoplasms / Q000401:mortality*; D004781:Environmental Exposure / Q000009:adverse effects / Q000706:statistics & numerical data*; D005260:Female; D015386:Hazardous Substances / Q000032:analysis* / Q000633:toxicity; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008669:Metallurgy; D008670:Metals / Q000032:analysis* / Q000633:toxicity; D008875:Middle Aged; D018570:Risk Assessment; D013030:Spain / Q000453:epidemiology; D055815:Young Adult
chemical_list: D015386:Hazardous Substances; D008670:Metals