Environmental lead exposure during early childhood.
OBJECTIVE
To determine the relative contribution of residential lead hazards to children's blood lead concentrations during early childhood.


METHODS
We enrolled children 6 months of age and followed them until 24 months of age. Blood and samples of dust, soil, water and paint were analyzed for lead at 6-month intervals, and interviews were conducted to estimate nutritional, behavioral, and demographic factors linked with lead exposure.


RESULTS
Of the 276 children enrolled, 249 (90%) were followed until 24 months of age. The geometric mean blood lead concentration of children at 6 months of age was 2.9 microg/dL (95% CI, 2.7-3.1). At 24 months of age, children's mean blood lead was 7.5 microg/dL; 82 (33%) had a blood lead level of > or = 10 microg/dL. In adjusted analyses, lead-contaminated floor dust, soil, and water contributed to children's lead intake throughout the first 2 years of life (P < .05). Lead-contaminated dust from window troughs was a source of lead exposure, especially in the second year of life. Dietary iron intake, but not calcium intake, was inversely associated with blood lead levels (P < .05). Blood lead concentration was over 50% higher in black than in white children (P = .0001).


CONCLUSIONS
Lead-contaminated house dust is the major source of lead intake during early childhood. Black children remain at increased risk for higher blood lead concentration after adjusting for environmental lead exposures and dietary intake.
Lanphear
Bruce P
BP
General and Community Pediatrics Department, Children's Hospital Medical Center, Cincinnati, OH 45229, USA.
Hornung
Richard
R
Ho
Mona
M
Howard
Cynthia R
CR
Eberly
Shirley
S
Knauf
Karen
K
Eberle
Shirley
S
D000367:Age Factors; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007854:Lead / Q000009:adverse effects* / Q000097:blood; D007855:Lead Poisoning / Q000097:blood / Q000453:epidemiology* / Q000208:ethnology; D015999:Multivariate Analysis; D012111:Residence Characteristics; D012307:Risk Factors
D007854:Lead