[Reference values for lead in blood in urban population in southern Brazil]. / Valores de referência para plumbemia em uma população urbana do Sul do Brasil.

OBJECTIVE: To describe the reference values for lead in blood in an urban population in the city of Londrina, in the state of Paraná, Brazil. MATERIALS AND METHODS: The reference population was composed of 520 adult volunteers who were assessed from November 1994 to December 1996. Exclusion criteria were: occupational exposure to lead, exposure through personal habits or practices, smoking more than 10 cigarettes per day, and living near industrial plants or other places that use lead in their production processes. Also excluded were individuals with abnormal clinical or laboratory results or with chronic diseases or cardiovascular disorders. Lead blood levels were determined using air-acetylene flame atomic absorption spectrophotometry. The detectable limit was 1.23 micrograms/dL. After the analyses of lead in blood, the following values were determined: minimum value, first quartile, median, third quartile, and maximum value; geometric mean; 95% confidence interval; experimental interval; and reference value. RESULTS: The reference values for lead in blood ranged from 1.20 micrograms/dL to 13.72 micrograms/dL. The geometric mean was 5.5 micrograms/dL. CONCLUSIONS: In general, the values found in this study are lower than those that have been reported for other countries. Additional data should be gathered from Brazilian populations living in more-industrialized areas.

[Reference values for lead levels in blood for the urban population]. / Valores de referência para plumbemia em população urbana.

INTRODUCTION: The lead reference values for blood used in Brazil come from studies conducted in other countries, where socioeconomic, clinical, nutritional and occupational conditions are significantly different. In order to guarantee an accurate biomonitoring of the population which is occupationally exposed to lead, a major health concern of the studied community, reference values for individuals who are not occupationally exposed and who live in the southern region of the city were established. MATERIAL AND METHOD: The sample was composed of 206 subjects of at least 15 years of age. Various strategies were employed to assure good-quality sampling. Subjects who presented values outside clinical or laboratory norms were excluded, as well as those whose specific activities might interfere with the results. RESULTS: Lead reference values for blood were found to be from 2.40 to 16.6 micrograms.dL-1, obtained by the interval x +/- 2s (where x is the mean and s is the standard deviation form observed values) and the median was 7.9 micrograms.dL-1.