Lead is distributed in the body into two pools, an active pool in the blood and soft tissues and a storage pool in bones and calcified tissues. In the blood, 95-98% of all the inorganic lead is bound in the erythrocytes. Chronic exposure will cause lead is accumulate in the bone, teeth, liver and brain. Since excretion of lead by the kidneys is very slow, it tends to accumulate in the body. Advanced lead intoxication will result in lead encephalopathy characterized by cerebral edema, come and convulsions. Children are specially susceptible to neurologic damage from lead and acute neurologic toxicity may develop without previous symptoms. Blood lead concentrations are monitored to assess toxicity and the course of treatment.