title: Maternal bone lead contribution to blood lead during and after pregnancy.
abstract: We examined bone lead contribution to blood lead in a group of 311 immigrant women, 99% from Latin America, during the third trimester of pregnancy and 1 to 2 months after delivery. We measured in vivo tibia and calcaneus (heel) bone lead concentration in the postdelivery period with K shell X-ray fluorescence. Prenatal and postnatal geometric mean (range) blood lead level was 2.2 microg/dL (0.4 to 38.7) and 2.8 microg/dL (0.4 to 25.4), reflecting low current exposure. Postnatal blood lead level was significantly higher than prenatal (P<0.0001). Mean (range) tibia and calcaneus lead concentration was 6.7 microg/g (-33.7 to 62.2) and 8.4 microg/g (- 30.1 to 66.4), reflecting varying but elevated past lead exposure. Mean calcaneus lead concentration was significantly higher than mean tibia lead concentration (P = 0.055). Variance-weighted multiple regression and structural equation models showed that both calcaneus and tibia lead were directly associated with prenatal blood lead but only calcaneus lead was associated with postnatal blood lead. Increasing natural log years in the United States independently predicted decreasing calcaneus and third-trimester blood lead. The data suggest that while some exogenous lead sources and modulators of blood lead level, such as use of lead-glazed pottery and calcium in the diet, control lead exposure during and after pregnancy, endogenous lead sources from past exposure before immigration continue to influence blood lead levels in this sample.
authors.affiliation: Department of Anesthesiology, Drew University of Medicine and Science, Los Angeles, California 90059, USA.
authors.forename: S J
authors.initials: SJ
authors.lastname: Rothenberg
authors.forename: F
authors.initials: F
authors.lastname: Khan
authors.forename: M
authors.initials: M
authors.lastname: Manalo
authors.forename: J
authors.initials: J
authors.lastname: Jiang
authors.forename: R
authors.initials: R
authors.lastname: Cuellar
authors.forename: S
authors.initials: S
authors.lastname: Reyes
authors.forename: S
authors.initials: S
authors.lastname: Acosta
authors.forename: M
authors.initials: M
authors.lastname: Jauregui
authors.forename: M
authors.initials: M
authors.lastname: Diaz
authors.forename: M
authors.initials: M
authors.lastname: Sanchez
authors.forename: A C
authors.initials: AC
authors.lastname: Todd
authors.forename: C
authors.initials: C
authors.lastname: Johnson
mesh_terms: D000293:Adolescent; D000328:Adult; D001842:Bone and Bones / Q000737:chemistry*; D004522:Educational Status; D005260:Female; D006630:Hispanic or Latino; D006801:Humans; D007854:Lead / Q000032:analysis / Q000097:blood*; D015141:Los Angeles; D049590:Postpartum Period; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D011795:Surveys and Questionnaires
chemical_list: D007854:Lead