Air Quality Criteria for Lead Volume II of II - (NEPIS)(EPA) - US ...

AX6-25
Table AX6-2.9. Effects of Lead on Direct Measures of Brain Anatomical Development and Activity in Children
Reference, Study
Location, and Period Study Description Pb Measurement Findings, Interpretation
United States
Trope et al. (1998)
U.S.
Trope et al. (2001)
U.S.
Cecil et al. (2005)
U.S.
Design: Case-control. One 10 yr-old subject with
history of Pb poisoning and unexposed 9 yr-old
cousin. Magnetic Resonance Imaging (MRI) and
Magnetic Resonance Spectroscopy (MRS) were
used to assess differences in cortical structures and
evidence of neuronal loss. This was the first study
to attempt to determine in vivo structural and/or
metabolic differences in the brain of a child
exposed to Pb compared with a healthy control.
Design: Case-control. 16 subjects with a history of
elevated blood Pb levels before 5 yrs of age and
5 age-matched siblings or cousins were evaluated.
Avg age at time of evaluation was 8 yrs. Magnetic
Resonance Imaging (MRI) and Magnetic
Resonance Spectroscopy (MRS) were used to
assess differences in cortical structures and
evidence of neuronal loss.
Design: Prospective/longitudinal. 48 young adults
ages 20 to 23 yrs were re-examined. Functional
MRI (fMRI) was used to examine the influence of
childhood Pb exposure on language function.
Subjects performed a verb generation/fingertapping
paradigm. Extensive measurement of
medical and sociodemographic covariates
Blood Pb
Pb poisoned case 51 µg/dL
at 38 mo
Unexposed control not
reported.
Blood Pb
Range in Pb-exposed 23 to
65 µg/dL
Controls