title: Variations in lead isotopic abundances in Sprague-Dawley rat tissues: possible reason of formation.
abstract: It has been reported in previous research that the lead isotopic composition of blood, urine and feces samples statistically differed from the given lead sources in Sprague-Dawley (SD) rats. However, the reason for this phenomenon is still unclear. An animal experiment was performed to investigate the lead isotope fractionation in diverse biological samples (i.e., lungs, liver, kidneys, bone) and to explore the possible reasons. SD rats were intratracheally instilled with lead acetate at the concentrations of 0, 0.02, 0.2, and 2 mg/kg body weight. Biological samples were collected for lead isotope analysis using an inductively coupled plasma mass spectrometry (ICP-MS). Significant differences are observed in lead isotope abundances among the diverse biological samples. The lead isotope abundances ((206)Pb, (207)Pb and (208)Pb) in diverse biological samples show different degrees and directions of departure from the given lead source. The results suggest that differences in enrichment or depletion capacity for each lead isotope in the various tissues might lead to the variation in lead isotopic abundances in tissues. Moreover, a nonlinear relationship between the blood lead level and the lead isotope abundances in liver and bone is observed. When the whole-blood level is higher than 50 ng/mL, the lead isotopic compositions of biological samples tend to be the same. Thus, the data support the speculation of a fractionation functional threshold.
authors.affiliation: School of Public Health, Peking University, Haidian District, Beijing, People's Republic of China.
authors.forename: Duojian
authors.initials: D
authors.lastname: Liu
authors.affiliation: School of Public Health, Peking University, Haidian District, Beijing, People's Republic of China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wu
authors.affiliation: School of Public Health, Peking University, Haidian District, Beijing, People's Republic of China ; Center of Medical and Health Analysis, Peking University, Beijing, People's Republic of China.
authors.forename: Li
authors.initials: L
authors.lastname: Ouyang
authors.affiliation: School of Public Health, Peking University, Haidian District, Beijing, People's Republic of China ; Center of Medical and Health Analysis, Peking University, Beijing, People's Republic of China.
authors.forename: Jingyu
authors.initials: J
authors.lastname: Wang
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001842:Bone and Bones / Q000378:metabolism*; D007554:Isotopes; D007668:Kidney / Q000378:metabolism*; D007854:Lead / Q000378:metabolism*; D008099:Liver / Q000378:metabolism*; D008168:Lung / Q000378:metabolism*; D008297:Male; D013058:Mass Spectrometry; D009942:Organometallic Compounds / Q000008:administration & dosage / Q000493:pharmacokinetics; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D007554:Isotopes; D009942:Organometallic Compounds; D007854:Lead; C008261:lead acetate