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Low-level lead exposure and children's cognitive function in the preschool years

Authors :
Bellinger, David
Sloman, Jone
Leviton, Alan
Rabinowitz, Michael
Needleman, Herbert L.
Waternaux, Christine
Source :
Pediatrics. Feb, 1991, Vol. v87 Issue n2, p219, 9 p.
Publication Year :
1991

Abstract

Several studies suggest that prenatal or infantile exposure to lead is associated with slower mental development, and that this occurs at levels that are lower than currently recognized as unsafe or elevated. However, the relationship between such early subclinical exposures and subsequent performance at preschool and school ages has not been established. The effect of lead exposure on cognitive (intellectual) development was evaluated in a group of 170 middle-class and upper-middle class children for approximately five years. Differences in blood lead levels measured at birth, an indicator of prenatal exposure, were not related to subsequent cognitive performance. However, elevated blood lead levels at 24 months significantly correlated with lower cognitive performance at 57 months of age; this was independent of social factors. Analysis showed that children with high levels of prenatal exposure 'recovered' better if postnatal lead exposure was low. Males improved less than females, and social factors such as class and maternal IQ also affected recovery. Deficits were most apparent in measures of visual-spatial and visual-motor integration skills. The results indicate that among socially advantaged children, prenatal exposure to lead or to low lead levels during early infancy may be overcome if lead exposure subsequently decreases. However, this likely represents optimum conditions; children with fewer advantages or those with greater or later lead exposure will probably have more cognitive development problems. (Consumer Summary produced by Reliance Medical Information, Inc.)

Details

ISSN :
00314005
Volume :
v87
Issue :
n2
Database :
Gale General OneFile
Journal :
Pediatrics
Publication Type :
Academic Journal
Accession number :
edsgcl.10421729