associated with an increased risk of lead intoxication in the occupants Other unusual sources of lead exposure include the burning of battery casings for heat or recycling of batteries, water carried by outdated lead pipes, improperly homeglazed ceramics, lead contamination of imported spices or cosmetics, and dust or dirt contaminated by vehicles which once used leaded gasoline Absorption of lead occurs through GI and pulmonary routes; the former is predominant in pediatric intoxications Lead is then compartmentalized into three main areas: bone, soft tissues, and blood Excretion occurs slowly through urine, feces, and sweat Children are probably at double jeopardy compared with adults; animal studies show that younger animals have increased absorption and also a heavier distribution into soft tissues (including the brain) Concomitant nutritional deficiency, especially low dietary iron and calcium, may enhance intestinal lead absorption Unfortunately, the same children at greatest risk for lead poisoning by virtue of age and residence are also likely to be at risk for dietary deficiency, especially iron Lead exerts its toxic effect principally by two mechanisms: (1) interference with calcium function at the cellular level and (2) enzyme inhibition, particularly enzymes rich in sulfhydryl groups In humans, the most obvious effects are on neurologic function and on the hemesynthesis pathway, which is interrupted at several points, resulting in abnormally high levels of porphyrins and their precursors Clinical Considerations Early signs and symptoms of plumbism are notably and nonspecific Abdominal complaints, including colicky pain, constipation, anorexia, and intermittent vomiting, are common; of course, these same symptoms are often ascribed to relatively normal 2-year-old children by their parents The child with early plumbism may also show listlessness and irritability When encephalopathy begins, the child develops persistent vomiting and becomes drowsy, clumsy, or frankly ataxic As encephalopathy worsens, the level of consciousness deteriorates further, and seizures commonly occur Pathologic examination of brains of children who have died of lead encephalopathy shows severe cerebral edema with vascular damage; intracranial pressure is often increased during the encephalopathy Peripheral neuropathy often occurs in adults with lead poisoning but is rare in children, although it is seen occasionally in those with an underlying hemoglobinopathy Other organs may be damaged by lead The kidneys may develop disturbances that range from slight aminoaciduria to a full Fanconi syndrome with glycosuria and phosphaturia (in addition to aminoaciduria) High blood lead level (BLL) is also associated with a microcytic