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

AX6-19
Table AX6-2.6. Effects of Lead on Disturbances in Behavior, Mood, and Social Conduct in Children
Reference, Study
Location, and Period Study Description Pb Measurement Findings, Interpretation
United States
Sciarillo et al. (1992)
U.S.
Bellinger et al. (1994b)
U.S.
Denno (1990)
U.S.
Design: Cross-sectional. 150 2-5 yr-old children in
Baltimore separated into “high” (2 consecutive blood
Pb levels >15 µg/dL) and “low” groups. Mothers
filled out the Achenbach Child Behavior Checklist
(CBCL). The Center for Epidemiologic Studies
Depression Scale (CESD) was administered to
mothers as a control measure.
Design: Prospective cohort: 1782 children born
within a 1-yr period at a single Boston hospital were
examined at 8 yrs of age. Teachers filled out the
Achenbach Child Behavior Profile (ACBP). Medical
and sociodemographic characteristics assessed by
questionnaire and chart review.
Design: Prospective cohort. Survey of 987
Philadelphia African-American youths enrolled in
the Collaborative Perinatal Project. Data available
from birth through 22 yrs of age. Analysis
considered 100 predictors of violent and chronic
delinquent behavior.
Screening blood Pbs at
various times before
assessment
High group 28.6
(SD 9.3) µg/dL
Low group 11.3
(SD 4.3) µg/dL
Umbilical cord blood Pb
Cord blood Pb 6.8
(SD 3.1) µg/dL
Tooth (dentin) Pb
Tooth Pb 3.4
(SD 2.4) µg/g
Blood Pb
Values not provided
When compared to lower exposed group, children in the
high group had a significantly higher CBCL Total
Behavior Problems Score (TBPS) and Internalizing and
Externalizing scores. After adjustment for maternal
depression, blood Pb concentrations were still significantly
associated with an increase in the TBPS. Children in high
group were nearly 3 times more likely to have a TBPS in
the clinical range. A significantly higher percentage of
children in the high group scored in the clinical range for
CBCL subscales measuring aggressive and destructive
behavioral tendencies.
Cord blood Pb levels were not associated with the
prevalence or nature of behavioral problems reported by
teachers. Tooth Pb levels were significantly associated
with ACBP Total Problem Behavior Scores (TPBS).
Statistically significant tooth Pb-associated increases in
both Externalizing and Internalizing scores were observed.
Each log unit increase in tooth Pb was associated with a
1.5-point increase in T scores for these scales. Authors
caution that residual confounding cannot be ruled out
because of the lack of information on parental
psychopathology or observations of the family
environment. However, these results are in accord with
other studies that social and emotional dysfunction may be
an important expression of elevated Pb levels during early
childhood.
Repeat offenders presented consistent features such as low
maternal education, prolonged male-provider
unemployment, frequent moves, and higher Pb
intoxication. In male subjects, a history of Pb poisoning
was among the most significant predictors of delinquency
and adult criminality.