The Legnica-Głogów Copper Mining District has been the site of metal mining for more than 50 years. Intensive environmental actions have, more recently, been aimed at reducing emissions of harmful substances in the region. We compared the blood lead concentrations of children resident in the copper smelting district in southwestern Poland in 1995 and 2007.
The sample included 1,405 children, 7-15 years of age, resident in the same communities in the Legnica- Głogów Copper Mining District in 1995 (432 boys, 403 girls) and 2007 (279 boys, 291 girls). Blood samples were drawn (venipuncture) and analyzed for lead levels (Pb-B) with the same protocol in both years (atomic absorption spectrometry in a graphite furnace). Analysis of covariance, with age and age squared as covariates, was used to compare blood lead levels between years, regions (Głogów and Legnica), and genders. The prevalence of children with blood lead levels >6 μg/dl was compared between years, regions, and genders, and was compared with the chi square statistic (χ²).
Blood lead level was significantly higher in 1995 (7.52±0.12 μg/dL) compared to 2007 (4.80±0.16 μg/dL), a decline of 2.72±0.19 μg/dL over the 12-year interval. Blood lead levels were higher in boys than in girls in each year, and declined between 1995 and 2007 in each gender, 8.61±0.16 μg/dL and 5.31±0.23 μg/dL, respectively, in boys, and 6.43±0.17 μg/dL and 4.29±0.22 μg/dL, respectively, in girls. Percentages of high blood lead levels (>6 μg/dL) were significantly higher in boys than girls in both years (1995: 77.5% and 51.9%, respectively; 2007: 32.6% and 16.5%, respectively), and declined significantly between 1995 and 2007 in both genders.
Blood lead levels decreased over the interval of 12 years in school children resident in the Legnica- Głogów Copper Mining District.