In 1980, a survey of lead poisoning was carried out among 592 children aged 1 to 9 years living within 900 m of a lead smelter in Santo Amaro, Brazil. From 1980 to 1985, the lead smelter carried out a number of major improvements aimed at reducing environmental pollution. In January, 1985, a second survey was carried out among a sample of 250 children living in this same geographical area. The geometric mean of zinc protoporphyrin (ZPP) concentration in whole blood was 1.17 (standard deviation = 1.5) mumol l-1. Blood lead concentrations (PbB) determined in a subsample of 53 children had an arithmetic mean and standard deviation of 1.77 +/- 1.00 mumol l-1, with 22 children showing PbB greater than or equal to 1.68 mumol l-1. Twenty-nine (11.6%) of the 250 children lived in houses where the lead content of the soil was greater than 10,000 ppm, and they presented higher ZPP levels than the rest of the population. Children with the habit of pica for soil had elevated ZPP levels. Comparing the results from the 1980 and 1985 surveys, slight improvements in ZPP and PbB levels were observed. However, new cases of lead poisoning are still occurring in the area. The soil is highly contaminated by lead and represents a long-lasting risk factor for child intoxication.