Beyer W Nelson, Basta Nicholas T, Chaney Rufus L, Henry Paula F P, Mosby David E, Rattner Barnett A, Scheckel Kirk G, Sprague Daniel T, Weber John S
US Geological Survey, Patuxent Wildlife Research Center, Beltsville, Maryland, USA.
School of Environment and Natural Resources, The Ohio State University, Columbus, Ohio, USA.
Environ Toxicol Chem. 2016 Sep;35(9):2311-9. doi: 10.1002/etc.3399. Epub 2016 Jun 6.
Hazards of soil-borne lead (Pb) to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb to birds, the authors measured blood Pb concentrations in Japanese quail (Coturnix japonica) fed diets containing Pb-contaminated soils. Relative bioavailabilities were expressed by comparison with blood Pb concentrations in quail fed a Pb acetate reference diet. Diets containing soil from 5 Pb-contaminated Superfund sites had relative bioavailabilities from 33% to 63%, with a mean of approximately 50%. Treatment of 2 of the soils with phosphorus (P) significantly reduced the bioavailability of Pb. Bioaccessibility of Pb in the test soils was then measured in 6 in vitro tests and regressed on bioavailability: the relative bioavailability leaching procedure at pH 1.5, the same test conducted at pH 2.5, the Ohio State University in vitro gastrointestinal method, the urban soil bioaccessible lead test, the modified physiologically based extraction test, and the waterfowl physiologically based extraction test. All regressions had positive slopes. Based on criteria of slope and coefficient of determination, the relative bioavailability leaching procedure at pH 2.5 and Ohio State University in vitro gastrointestinal tests performed very well. Speciation by X-ray absorption spectroscopy demonstrated that, on average, most of the Pb in the sampled soils was sorbed to minerals (30%), bound to organic matter (24%), or present as Pb sulfate (18%). Additional Pb was associated with P (chloropyromorphite, hydroxypyromorphite, and tertiary Pb phosphate) and with Pb carbonates, leadhillite (a lead sulfate carbonate hydroxide), and Pb sulfide. The formation of chloropyromorphite reduced the bioavailability of Pb, and the amendment of Pb-contaminated soils with P may be a thermodynamically favored means to sequester Pb. Environ Toxicol Chem 2016;35:2311-2319. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US Government work and, as such, is in the public domain in the United States of America.
如果已知土壤中铅（Pb）的生物有效性，那么土壤中铅对野生鸟类的危害可能会得到更准确的量化。为了更好地了解铅对鸟类的生物有效性，作者测量了喂食含铅污染土壤日粮的日本鹌鹑（Coturnix japonica）的血液铅浓度。通过与喂食醋酸铅参考日粮的鹌鹑的血液铅浓度进行比较来表示相对生物有效性。含有来自5个铅污染超级基金场地土壤的日粮的相对生物有效性为33%至63%，平均约为50%。用磷（P）处理其中2种土壤显著降低了铅的生物有效性。然后在6项体外试验中测量了试验土壤中铅的生物可及性，并将其与生物有效性进行回归分析：pH值为1.5时的相对生物有效性浸出程序、在pH值为2.5时进行的相同试验、俄亥俄州立大学体外胃肠道方法、城市土壤生物可及性铅试验、改良的基于生理学的提取试验以及水禽基于生理学的提取试验。所有回归分析都有正斜率。根据斜率和决定系数的标准，pH值为2.5时的相对生物有效性浸出程序和俄亥俄州立大学体外胃肠道试验表现非常好。通过X射线吸收光谱法进行的形态分析表明，平均而言，采样土壤中大部分铅被吸附到矿物质上（30%）、与有机物结合（24%）或以硫酸铅形式存在（18%）。额外的铅与磷（氯磷灰石、羟磷灰石和三级磷酸铅）以及碳酸铅、羟碳铅矿（一种硫酸碳酸氢氧化铅）和硫化铅有关。氯磷灰石的形成降低了铅的生物有效性，用磷改良铅污染土壤可能是一种热力学上有利的固定铅的方法。《环境毒理学与化学》2016年；35：2311 - 2319。2016年由威利期刊公司代表SETAC出版。本文是美国政府的作品，因此在美国属于公共领域。
