[Screening for lead poisoning in children by measuring lead levels in housing: a study of the Paris region].

Screening programs for lead poisoning in France rely usually on the preliminary identification of risk factors among children seen in Maternal and Child Health (MCH) clinics. To assess the potential relevance of screening strategies based on the quantification of exposure to lead in housing, we estimated first the prevalence of exposure to lead in a representative sample of older buildings, then the prevalence of lead poisoning among children living in those buildings where high levels of lead had been found. Exposure to lead was measured in dust and paint samples collected in hallways and other collective areas of the buildings. Venous blood samples were collected from the children aged 10 months to 6 years residing in buildings where lead exceeded 1.5 g/kg in paint samples or 1000 micrograms/m2 in dust samples. Paint and dust samples were collected in 137 buildings: 74% presented high dust and/or paint lead contents. Blood samples were collected from 145 out of a total of 189 children residing in these buildings: blood lead levels (PbB) were higher than or equal to 10 micrograms/dl for 65% of these children; 29% were higher than or equal to 15 micrograms/dl, 16% higher than or equal to 20 micrograms/dl. Out of 42 children with PbB > or = 15 micrograms/dl, 21 had not been previously identified through the screening program conducted in local MCH clinics. Clinic-based and environment-based screening appeared to be complementary. It seems thus justified to develop screening strategies based on the assessment of exposure to lead in the environment.