Some biochemical indices of lead and cadmium exposure in healthy and protein-energy malnutrition [PEM] children in Assiut locality

ABSTRACT

Due to the recent interest in childhood trace metal intoxication, lead, cadmium and iron plasma concentrations together with zeta-aminolevulinic acid dehydrase [ALA-dehydrate] activity levels were determined in a total of 183 children [144 healthy aged 6 months to 12 years and 39 PEM aged 6 to 36 months]. Taking 3 micro g/dL as the cut-off level, about 24% of the healthy and about 26% of the PEM children had plasma levels above this value. Such increment in lead level was accompanied by significantly decreased hemoglobin concentrations. Plasma lead levels were significantly higher in children who are residing in urban than in those who are residing in rural areas. In the group of healthy children with plasma, lead levels above 3 micro g/dL the significant risk factors were residence in urban areas and history of pica [71.4% for each]. ALA-dehydrase activity was significantly lower and its activation ratio was significantly higher in children with plasma lead, level > 3 ug/dL than in those with lower levels. A significant negative correlation and a significant positive one were found between plasma lead level on one hand and both ALA-dehydrase activity and its activation ratio respectively on the other hand. ALA-dehydrase activity was significantly lower whereas its activation ratio was significantly higher in children who are residing in urban than in those residing in rural areas. Plasma, cadmium levels were increased significantly with age. Significant risk factors for increasing cadmium levels include urban residence, indoor parents smoking and protein energy malnutrition. It was concluded that children in urban areas are at great risk for lead and cadmium exposure than those in rural areas. Also, ALA-dehydrase activities and its activation ratio can serve as good indicators for early detection of ill health due to lead exposure