Lead exposure in children living in a smelter community in Region Lagunera, Mexico

Industrial growth has created the potential for environmental problems in M exico, since attention to environmental controls and urban planning has lag ged behind the pace of industrialization. The aim of this cross-sectional s tudy was to assess lead exposure in children aged 6-9 yr attending 3 primar y schools and living in the vicinity of the largest smelter complex in Mexi co. One of the schools is located 650 m distant from a smelter complex that includes a lead smelter (close school); the second is located 1750 m away from the complex and at the side of a heavy traffic road (intermediate scho ol) in Torreon, Coahuila. The third school is located in Gomez Palacio, Dur ango, 8100 m away from the smelter complex and distant from heavy vehicular traffic or industrial areas ( remote school). Lead was measured in air, so il, dust, and well water. Lead in blood (PbB) was determined in 394 childre n attending the above mentioned schools. Determinations were performed by a tomic absorption spectrometry. Diet, socioeconomic status, hygienic habits, and other variables were assessed by questionnaire. Median (range) PbB val ues were 7.8 mug/dl (3.54-29.61) in the remote school, 21.8 mug/dl(8.37-52. 08) in the intermediate school and 27.6 mug/dl (7.37-58.53) in children att ending the close school. The percentage of children with PbB >15 mug/dl was 6.8%, 84.9%, and 92.1% respectively. In this order, the geometric means ( range) of Pb concentrations in air were 2.5 mug/m(3) (1.1-7.5), 5.8 mug/m(3 ) (4.3-8.5), and 6.1 mug/m(3) (1.6-14.9). The Pb concentrations in dust fro m playgrounds areas in the intermediate and close school settings ranged fr om 1457 to 4162.5 mg/kg. Pb concentrations in drinking water were less than 5 mug/L. Soil and dust ingestion and inhalation appear to be the main rout es of exposure. Our results indicate that environmental contamination has r esulted in an increased body burden of Pb, suggesting that children living in the vicinity of the smelter complex are at high risk for adverse effects of lead.