| dc.description.abstract | Overt poisoning by some trace elements (Cu, Hg, Mn, Pb) is known to cause extensive central nervous system damage which can result in mental retardation. Recent evidence indicates that low, undetectable exposure to lead may have deleterious effects on mental functioning and behavior. This study took the first step in examining the hypothesis that one factor in the cause of some mental retardation is the effects of subclinical levels of lead and other toxic trace elements. The objective was to investigate the relationship between levels of trace elements and mental functioning in children with a diagnosis of mental retardation due to unspecified causes.
Nine males and fourteen females, ranging in age from three years, two months to 13 years, one month, were selected from a state-operated institution. Head hair samples from each subject are being analyzed for cadmium, copper, iron, lead, manganese, mercury, and zinc content. The effects of a wide variety of factors including age, sex, race, neurological disorders in addition to mental retardation, length of institutionalization, diet, exercise, hair color, geographic residence prior to institutionalization, family income, family size, education of parents, and occupation of parents on trace elements are being considered.
Preliminary data indicates that hair copper content for mentally retarded subjects are slightly higher than for normal children their age. IQ was not significantly correlated with copper levels. However, significant correlations between copper levels and sex (r=0.39), race (r=-0.46), and activity level (r=-0.54) were observed | en |
