title: Association of blood lead levels with urinary F₂-8α isoprostane and 8-hydroxy-2-deoxy-guanosine concentrations in first-grade Uruguayan children.
abstract: Oxidative stress (OS) is a potential molecular mechanism for lead-induced toxicities, yet, we have limited understanding of the relation between low-level lead (Pb) exposure and OS, especially in children. This cross-sectional study examines the association between blood lead level (BLL) and two OS markers-urinary F2-8α isoprostane or isoprostane (a marker of lipid peroxidation) and 8-hydroxy-2-deoxy-Guanosine or 8-OH-dG (a marker of DNA damage) in 211 children, aged 5-8 years, from Montevideo, Uruguay. The role of dietary intakes of vitamin C and zinc in modifying the relation between BLL and OS was also examined. The mean (SD) BLL of the study children was 4.7 (2.2) µg/dL, with 30.2% children having BLL ≥5 µg/dL, the current reference level set by the US Centre for Disease Control for identifying, monitoring and management of children with elevated BLL. In covariate-adjusted analysis, there was a weak positive association between BLL and urinary isoprostane (adjusted for specific gravity) [β=0.09, p<0.1]. No association was found between children's BLL and urinary 8-OH-dG. Interactions between dietary intakes of vitamin C or zinc and BLL on OS biomarkers were not consistent. However, when BLL and vitamin C or BLL and zinc were modeled together, BLL was independently associated with isoprostane concentration [β=0.10, p<0.05] but vitamin C or zinc intake was not. These findings suggest that there may be a potential adverse effect of BLL on OS in children with low-level Pb exposure. There is a need to study the effects of Pb on other OS measures, as well as the role of OS in mediating low-level Pb toxicity on functional outcomes.
authors: Department of Nutritional Sciences, Pennsylvania State University, University Park, USA. Electronic address: axr977@psu.edu.
authors: Aditi
authors: A
authors: Roy
authors: Centre for Research, Catholic University of Uruguay, Montevideo, Uruguay.
authors: Elena
authors: E
authors: Queirolo
authors: Centre for Research, Catholic University of Uruguay, Montevideo, Uruguay; Department of Gastroenterology, Hepatology and Nutrition, Hospital Pereira Rossell, Montevideo, Uruguay.
authors: Fabiana
authors: F
authors: Peregalli
authors: Faculty of Chemistry, University of the Republic of Uruguay, Montevideo, Uruguay.
authors: Nelly
authors: N
authors: Mañay
authors: Faculty of Chemistry, University of the Republic of Uruguay, Montevideo, Uruguay.
authors: Gabriela
authors: G
authors: Martínez
authors: Department of Nutritional Sciences, Pennsylvania State University, University Park, USA; School of Social and Community Medicine, University of Bristol, Bristol, UK.
authors: Katarzyna
authors: K
authors: Kordas
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D002648:Child; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000652:urine; D004781:Environmental Exposure; D028441:F2-Isoprostanes / Q000652:urine*; D005260:Female; D006801:Humans; D007854:Lead / Q000097:blood* / Q000633:toxicity; D008297:Male; D018384:Oxidative Stress; D014583:Uruguay
chemical_list: D028441:F2-Isoprostanes; D007854:Lead; D000080242:8-Hydroxy-2'-Deoxyguanosine; D003849:Deoxyguanosine
keywords: 8-hydroxy-2-deoxy-guanosine; Child; DNA damage; Isoprostane; Lead; Lipid peroxidation; Oxidative stress; Pb; School-age; Uruguay