Blood lead level and its relationship to essential elements in preschool children from Nanning, China

Objective: Our study aimed to assess the distribution of blood lead level and its relationship to essential elements in preschool children in an urban area of China. Design and methods: A total of 6741 children aged 0- to 6-year-old were recruited. Levels of lead, zinc, copper, iron, calcium, and magnesium in whole blood samples were determined using atomic absorption spectrometry. Results: The mean blood lead level (BLL) and the prevalence of BLL >= 10 mu g/dl (5.26 +/- 4.08 mu g/dl and 6.84%, respectively) increased with age gradually, and there was a gender-difference for blood lead, copper, zinc and iron levels. Compared with the group of children who had BLLs < 5 mu g/dl, the groups of 5 <= BLLs < 10 mu g/dl and 10 <= BLLs < 15 mu g/dl showed higher blood zinc, iron and magnesium levels, and a lower blood calcium level. A positive correlation of lead with zinc, iron and magnesium, and a negative correlation of lead with calcium were found in the group of children with BLL < 5 mu g/dl. Conclusion: Age- and gender-differences were found when assessing the BLL and intoxication prevalence in preschool children. Metabolic disorder of essential elements was found even with a low level of lead exposure. (C) 2014 Elsevier GmbH. All rights reserved.