title: Bone lead and endogenous exposure in an environmentally exposed elderly population: the normative aging study.
abstract: OBJECTIVE
  The objective of this study is to investigate the mobilization of lead from bone to blood (endogenous exposure) in a large epidemiologic population.
  
  
  METHODS
  Study subjects were 776 participants in the Normative Aging Study. The subjects had their tibia lead, patella lead, blood lead, and urinary N-telopeptide (NTx) levels measured 1 to 4 times from 1991 to 2002. Regression models were estimated to quantify the association between tibia and patella lead and blood lead. We studied nonlinearity of the association, and explored possible factors that may modify it, including age and NTx levels.
  
  
  CONCLUSIONS
  There is significant association between bone lead and blood lead, and the association is nonlinear. The nonlinear associations between blood lead and bone lead are not significantly modified by age and NTx.
authors.affiliation: Department of Environmental Health, Harvard School of Public Health, Boston, MA, USA. nieh@hsph.harvard.edu
authors.forename: Huiling
authors.initials: H
authors.lastname: Nie
authors.forename: Brisa N
authors.initials: BN
authors.lastname: Sánchez
authors.forename: Elissa
authors.initials: E
authors.lastname: Wilker
authors.forename: Marc G
authors.initials: MG
authors.lastname: Weisskopf
authors.forename: Joel
authors.initials: J
authors.lastname: Schwartz
authors.forename: David
authors.initials: D
authors.lastname: Sparrow
authors.forename: Howard
authors.initials: H
authors.lastname: Hu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001842:Bone and Bones / Q000737:chemistry*; D001900:Boston; D024042:Collagen Type I / Q000652:urine; D006801:Humans; D007854:Lead / Q000097:blood* / Q000493:pharmacokinetics; D008297:Male; D008875:Middle Aged; D010329:Patella / Q000737:chemistry; D010455:Peptides / Q000652:urine; D012044:Regression Analysis; D013977:Tibia / Q000737:chemistry; D055815:Young Adult
chemical_list: D024042:Collagen Type I; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D007854:Lead