Nakata Hokuto, Nakayama Shouta M M, Yabe John, Liazambi Allan, Mizukawa Hazuki, Darwish Wageh Sobhy, Ikenaka Yoshinori, Ishizuka Mayumi
Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18 Nishi 9, Kita-ku, Sapporo 060-0818, Japan.
The University of Zambia, School of Veterinary Medicine, P.O. Box 32379, Lusaka, Zambia.
Environ Pollut. 2016 Jan;208(Pt B):395-403. doi: 10.1016/j.envpol.2015.10.006. Epub 2015 Nov 6.
Stable Pb isotope ratios (Pb-IRs) have been recognized as an efficient tool for identifying sources. This study carried out at Kabwe mining area, Zambia, to elucidate the presence or absence of Pb isotope fractionation in goat and chicken, to evaluate the reliability of identifying Pb pollution sources via analysis of Pb-IRs, and to assess whether a threshold for blood Pb levels (Pb-B) for biological fractionation was present. The variation of Pb-IRs in goat decreased with an increase in Pb-B and were fixed at certain values close to those of the dominant source of Pb exposure at Pb-B > 5 μg/dL. However, chickens did not show a clear relationship for Pb-IRs against Pb-B, or a fractionation threshold. Given these, the biological fractionation of Pb isotopes should not occur in chickens but in goats, and the threshold for triggering biological fractionation is at around 5 μg/dL of Pb-B in goats.
稳定铅同位素比值（Pb-IRs）已被公认为识别来源的有效工具。本研究在赞比亚的卡布韦矿区开展，以阐明山羊和鸡体内是否存在铅同位素分馏，评估通过分析Pb-IRs识别铅污染源的可靠性，并评估是否存在生物分馏的血铅水平（Pb-B）阈值。山羊体内Pb-IRs的变化随Pb-B的增加而减小，并在Pb-B>5μg/dL时固定在接近主要铅暴露源的值。然而，鸡的Pb-IRs与Pb-B之间没有明显关系，也没有分馏阈值。基于这些，铅同位素的生物分馏不应发生在鸡身上，而应发生在山羊身上，触发生物分馏的阈值约为山羊体内5μg/dL的Pb-B。
