Recognition and management of children with increased lead absorption.

Childhood lead poisoning has been increasingly recognised in the USA where large-scale screening programmes detect some 40 000 cases of undue lead absorption a year. This contrasts with data from the UK where about 100 cases are recognised each year. The situation in other countries is largely unknown, although small surveys have revealed cases from a wide variety of sources. These apparent discrepancies probably reflect differences in clinical awareness, the availability of practical screening tests, and differences in the definition of acceptable degrees of exposure. Within the last few years practical and effective screening tests for the early detection of undue lead absorption have been developed, but these have not been generally introduced. They include the determination of lead and erythrocyte protoporphyrin (FEP) in microlitre samples of blood. These tests have provided evidence of undue lead absorption from previously unrecognised sources. Thus, dusts contaminated with lead derived from atmospheric deposition, industrial clothing, and degradation of paint films, have now been shown to be important contributory factors. Many children thus affected are asymptomatic, and classical childhood plumbism and encephalopathy at present are rare. The identification of asymptomatic children has as its objective the institution of effective management in order to prevent serious poisoning and its consequences, and to diminish the potential risks of prolonged low level overexposure. While these risks have not been conclusively demonstrated, it has nevertheless been suggested that subtle neural and behavioural impairments may occur. Moreover, the existence of some children in the population with