Effect of environmental exposure to lead and tobacco smoke on inattentive and hyperactive symptoms and neurocognitive performance in children.
BACKGROUND
The present study assessed the association between blood lead and urinary cotinine levels and inattentive and hyperactive symptoms and neurocognitive performance in children.


METHODS
A total of 667 children (age range 8-11) were recruited from nine schools in five Korean cities. The teachers and parents completed the Korean version of the Attention-deficit/hyperactivity disorder Rating Scales (K-ARS), and the children performed neurocognitive tests. Blood lead and urinary cotinine levels were then measured.


RESULTS
The inattentive, hyperactive, and total scores of the teacher-rated K-ARS were positively associated with blood lead level, and the results of the continuous performance test (CPT), Stroop Color-Word Test, and Children's Color Trails Test were inversely associated with urinary cotinine level when controlled for age, gender, father's educational level, maternal IQ, child's IQ, residential area, birth weight, and cotinine (for lead) or lead (for cotinine). The association between blood lead level and commission errors score on the CPT disappeared when the effect of urinary cotinine level was controlled.


CONCLUSIONS
These findings indicate that environmental exposure to tobacco smoke in children is associated with poor neurocognitive performance, and low levels of lead are associated with inattention and hyperactivity symptoms.
Cho
Soo-Churl
SC
Division of Child and Adolescent Psychiatry, Department of Neuropsychiatry, Seoul National University College of Medicine, Seoul, Korea.
Kim
Boong-Nyun
BN
Hong
Yun-Chul
YC
Shin
Min-Sup
MS
Yoo
Hee Jeong
HJ
Kim
Jae-Won
JW
Bhang
Soo-Young
SY
Cho
In Hee
IH
Kim
Hyo-Won
HW
D000704:Analysis of Variance; D001289:Attention Deficit Disorder with Hyperactivity / Q000097:blood / Q000453:epidemiology* / Q000652:urine; D015984:Causality; D002648:Child; D003072:Cognition Disorders / Q000097:blood / Q000453:epidemiology* / Q000652:urine; D003367:Cotinine / Q000652:urine*; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007723:Korea / Q000453:epidemiology; D007854:Lead / Q000097:blood*; D008297:Male; D009483:Neuropsychological Tests / Q000706:statistics & numerical data*; D017678:Sex Distribution; D014028:Tobacco Smoke Pollution / Q000706:statistics & numerical data*
D014028:Tobacco Smoke Pollution; D007854:Lead; D003367:Cotinine