Lead exposure and motor functioning in 4 1/2 -year-old children: The Yugoslavia prospective study

Objective: To investigate associations between lead exposure and early motor development. Study design: We conducted standardized assessments of motor function (Bruininks-Oseretsky Test of Motor Proficiency and Beery Developmental Test of Visual-Motor Integration) at age 54 months in 283 children whose mothers were recruited in pregnancy from a smelter town and a non-lead-exposed town in Yugoslavia and who have been monitored twice yearly since birth. Blood lead concentration (BPb) was summarized in a measure reflecting the average of the child's semiannual serial log BPbs through 54 months. Results: Multiple regression showed that taken together, anthropometric measures (birth weight, body mass index) and markers of a stimulating and organized home life (HOME scale, parental education and intelligence, availability of siblings) explained a significant 10% to 18% of the variance in motor functioning. Beyond these contributions, BPb was significantly associated with poorer fine motor and visual motor function but was unrelated to gross motor coordination. Conclusions: Modest associations between early lead exposure and fine motor and visual motor functioning appear even after statistical adjustment is done for other contributors to motor development. Associations with BPb are specific to these areas of motor skill; gross motor development was unaffected.