title: Biomarker evidence of tobacco smoke exposure in children participating in lead screening.
abstract: OBJECTIVE
  We assessed tobacco smoke exposure (TSE), defined according to detection of cotinine, in dried blood spots collected from children for lead screening.
  
  
  METHODS
  Dried blood spots collected from a national sample of 1541 Black and White children and submitted to a commercial laboratory for lead analysis were analyzed for cotinine. We used an anonymous administrative data set including information on children's characteristics to conduct univariate and multivariate analyses.
  
  
  RESULTS
  Cotinine was detected in 61% of dried blood spots; 17% of samples had cotinine levels above 3 nanograms per gram. Median cotinine levels were significantly higher among Black than White children (0.66 ng/g vs 0.30 ng/g) and among Medicaid recipients (0.94 ng/g vs < 0.3 ng/g). In multivariate analyses, significant increases in cotinine levels were associated with Black (vs White) race, older age, Medicaid coverage, higher state smoking rate, and higher average winter temperature. Detectable cotinine levels were significantly associated with higher lead levels.
  
  
  CONCLUSIONS
  TSE is highly prevalent among children undergoing lead screening, and exposure levels are greater among Black children and children on Medicaid. TSE may contribute to lead exposure. Concurrent lead screening and biological screening for TSE may be a feasible approach to increasing childhood TSE detection.
authors.affiliation: Anne Joseph is with the Department of Medicine, Masonic Cancer Center, University of Minnesota, Minneapolis. Logan Spector is with the Department of Pediatrics, Masonic Cancer Center, University of Minnesota. Katherine Wickham is with the Masonic Cancer Center, University of Minnesota. Gregory Janis is with MEDTOX Laboratories, St. Paul, MN. Jonathan Winickoff is with the Center for Child and Adolescent Health Research and Policy and the Department of Pediatrics, Massachusetts General Hospital and Harvard Medical School, Boston. Bruce Lindgren is with the Biostatistics and Bioinformatics Core, University of Minnesota. Sharon Murphy is with the Department of Biochemistry, Molecular Biology and BioPhysics, Masonic Cancer Center, University of Minnesota.
authors.forename: Anne
authors.initials: A
authors.lastname: Joseph
authors.forename: Logan
authors.initials: L
authors.lastname: Spector
authors.forename: Katherine
authors.initials: K
authors.lastname: Wickham
authors.forename: Gregory
authors.initials: G
authors.lastname: Janis
authors.forename: Jonathan
authors.initials: J
authors.lastname: Winickoff
authors.forename: Bruce
authors.initials: B
authors.lastname: Lindgren
authors.forename: Sharon
authors.initials: S
authors.lastname: Murphy
mesh_terms: D015415:Biomarkers / Q000097:blood; D044383:Black People / Q000706:statistics & numerical data; D002675:Child, Preschool; D016001:Confidence Intervals; D003367:Cotinine / Q000097:blood*; D003430:Cross-Sectional Studies; D005260:Female; D006306:Health Surveys; D006801:Humans; D007223:Infant; D007854:Lead / Q000097:blood*; D008297:Male; D008403:Mass Screening; D014028:Tobacco Smoke Pollution / Q000032:analysis*; D014481:United States; D044465:White People / Q000706:statistics & numerical data; D001741:Black or African American
chemical_list: D015415:Biomarkers; D014028:Tobacco Smoke Pollution; D007854:Lead; D003367:Cotinine