title: Parental exposure to carcinogens and risk for childhood acute lymphoblastic leukemia, Colombia, 2000-2005.
abstract: BACKGROUND
  The objective of this study was to determine the risk factors for childhood acute lymphoblastic leukemia (ALL) and, in particular, the role of parental occupational exposure to carcinogenic and probably carcinogenic hydrocarbons before the child's conception.
  
  
  METHODS
  For this case-control study, cases were children younger than 15 years who were newly diagnosed with ALL between January 2000 and March 2005 at 1 of 6 Colombian hospitals. An interview with both parents of 170 children (85 cases and 85 individually matched neighborhood controls) gathered information about each child's exposures and parental demographic and occupational characteristics, medical history, health risk behaviors, and pregnancy and birth history. A job-exposure matrix was used to classify parental exposure to hydrocarbons on the basis of the main industrial activity of each workplace where parents worked before (both parents) or during the index pregnancy (mother only). Conditional odds ratios and 95% confidence intervals were calculated by period of exposure (preconception, pregnancy, and childhood).
  
  
  RESULTS
  The risk of childhood ALL was linked to 1) parental occupational exposure to hydrocarbons before conception, 2) parental smoking before conception, 3) maternal low socioeconomic status during pregnancy, and 4) higher maternal age (≥35 y) at the child's birth.
  
  
  CONCLUSIONS
  These findings suggest an association between childhood ALL and parental occupational exposure to carcinogenic and probably carcinogenic hydrocarbons before conception. Outcomes depended on the parent exposed. Future research should investigate the additive or multiplicative role of other environmental sources of hydrocarbons.
authors.affiliation: Centro de Investigaciones Epidemiológicas, Facultad de Salud, Universidad Industrial de Santander, Carrera 32 No. 29-31 (Piso 3), Bucaramanga, Colombia. mcastro2505@yahoo.es
authors.forename: Miguel Ángel
authors.initials: MÁ
authors.lastname: Castro-Jiménez
authors.forename: Luis Carlos
authors.initials: LC
authors.lastname: Orozco-Vargas
mesh_terms: D000293:Adolescent; D000328:Adult; D002273:Carcinogens / Q000633:toxicity*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003105:Colombia / Q000453:epidemiology; D004781:Environmental Exposure; D004785:Environmental Pollutants / Q000633:toxicity*; D005260:Female; D006801:Humans; D006838:Hydrocarbons / Q000633:toxicity*; D008297:Male; D008423:Maternal Age; D018811:Maternal Exposure; D016273:Occupational Exposure; D018812:Paternal Exposure; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000139:chemically induced* / Q000453:epidemiology; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D012307:Risk Factors; D012907:Smoking; D012959:Socioeconomic Factors; D013997:Time Factors
chemical_list: D002273:Carcinogens; D004785:Environmental Pollutants; D006838:Hydrocarbons