title: Complex organochlorine pesticide mixtures as determinant factor for breast cancer risk: a population-based case-control study in the Canary Islands (Spain).
abstract: BACKGROUND
  All the relevant risk factors contributing to breast cancer etiology are not fully known. Exposure to organochlorine pesticides has been linked to an increased incidence of the disease, although not all data have been consistent. Most published studies evaluated the exposure to organochlorines individually, ignoring the potential effects exerted by the mixtures of chemicals.
  
  
  METHODS
  This population-based study was designed to evaluate the profile of mixtures of organochlorines detected in 103 healthy women and 121 women diagnosed with breast cancer from Gran Canaria Island, and the relation between the exposure to these compounds and breast cancer risk.
  
  
  RESULTS
  The most prevalent mixture of organochlorines among healthy women was the combination of lindane and endrin, and this mixture was not detected in any affected women. Breast cancer patients presented more frequently a combination of aldrin, dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD), and this mixture was not found in any healthy woman. After adjusting for covariables, the risk of breast cancer was moderately associated with DDD (OR = 1.008, confidence interval 95% 1.001-1.015, p = 0.024).
  
  
  CONCLUSIONS
  This study indicates that healthy women show a very different profile of organochlorine pesticide mixtures than breast cancer patients, suggesting that organochlorine pesticide mixtures could play a relevant role in breast cancer risk.
authors.affiliation: Dpt of Clinical Sciences, Universidad de Las Palmas de Gran Canaria and Instituto Canario de Investigación del Cáncer-ICIC, P.O. Box 550, Las Palmas de Gran Canaria 35080, Spain. ldominguez@dcc.ulpgc.es
authors.forename: Luis D
authors.initials: LD
authors.lastname: Boada
authors.forename: Manuel
authors.initials: M
authors.lastname: Zumbado
authors.forename: Luis Alberto
authors.initials: LA
authors.lastname: Henríquez-Hernández
authors.forename: Maira
authors.initials: M
authors.lastname: Almeida-González
authors.forename: Eva E
authors.initials: EE
authors.lastname: Alvarez-León
authors.forename: Lluis
authors.initials: L
authors.lastname: Serra-Majem
authors.forename: Octavio P
authors.initials: OP
authors.lastname: Luzardo
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000139:chemically induced* / Q000453:epidemiology; D016022:Case-Control Studies; D002849:Chromatography, Gas; D004781:Environmental Exposure; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000097:blood / Q000633:toxicity*; D062665:Epidemiological Monitoring; D005260:Female; D006801:Humans; D006843:Hydrocarbons, Chlorinated / Q000097:blood / Q000633:toxicity*; D015994:Incidence; D007306:Insecticides / Q000097:blood / Q000633:toxicity*; D008875:Middle Aged; D008954:Models, Biological; D015233:Models, Statistical; D012307:Risk Factors; D013030:Spain / Q000453:epidemiology
chemical_list: D004785:Environmental Pollutants; D006843:Hydrocarbons, Chlorinated; D007306:Insecticides