Lead exposure in waterfowl was studied using noninvasive fecal sampling in the Guadalquivir Marshes in Spain, an area affected by the 1998 Aznalcóllar mine disaster. Feces of greylag geese (Anser anser, n = 191) and purple gallinule (Porphyrio porphyrio, n = 91) were collected from three different impacted sites (Entremuros, Caracoles and Cerro de los Ánsares) during the winters of 2004 to 2008. Lead and aluminium (an indicator of sediment ingestion) and Pb isotope signatures (to discriminate between sources of Pb exposure) were analyzed in freeze-dried, acid digested samples. The concentrations of fecal porphyrins and biliverdin were determined as noninvasive biomarkers to study Pb exposure effects. Results showed a decrease in Pb exposure over time in wintering greylag geese. In contrast, for purple gallinule resident in the Entremuros a clear trend was not evident. For both species, sediment ingestion appeared to be the main source of exposure to Pb. In the Entremuros, some samples from purple gallinule were detected with higher Pb levels than expected for simple soil ingestion, and these had Pb isotopic profiles compatible with mining sludge or Pb shot. Whilst fecal Pb isotopic profiles were effective in differentiating between samples from sites with different levels and sources of pollution, the combined use of element ratios (such as Pb/Al) and other non-traditional stable isotope signatures may also prove worthwhile. Overall, the fecal Pb levels detected were below those described in feces for waterfowl from other uncontaminated areas(<10 µg/g d.w.). Despite this, for both species fecal Pb levels were positively correlated with porphyrin excretion, and for purple gallinule, with the coproporphyrin III/I ratio, suggesting some subtle effects on heme synthesis in birds. Ten years after the mine spill, Pb contamination in birds by this pollution source was still detectable and subtlethal effects may persist.
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机译：水鸟中的铅暴露是在西班牙瓜达尔基维尔湿地的无创粪便采样中进行的，该地区受1998年阿兹纳尔库拉雷矿山灾害的影响。在2004年至2008年的冬季，从三个不同的受灾地点（Entremuros，Caracoles和Cerro de losÁnsares）收集了灰雁（Anser anser，n = 191）和紫鸡（Porphyrio porphyrio，n = 91）的粪便。铅和在冷冻干燥，酸消解的样品中分析了铝（沉积物摄入的指标）和铅同位素特征（以区分铅暴露源）。粪便中的卟啉和biliverdin的浓度被确定为研究Pb暴露影响的非侵入性生物标志物。结果表明，越冬灰雁的Pb暴露随时间减少。相反，对于居住在Entremuros的紫色鸡胆，没有明显的趋势。对于这两个物种，沉积物的摄入似乎都是铅暴露的主要来源。在Entremuros中，从紫色鸡胆中检出的一些Pb含量高于简单土壤摄入所预期的Pb含量，并且这些Pb的同位素特征与采矿污泥或Pb铅含量兼容。尽管粪便中的Pb同位素图谱可以有效地区分不同污染水平和污染源的样品，但元素比例（例如Pb / Al）和其他非传统的稳定同位素特征的组合使用也可能是值得的。总体而言，从其他未污染地区检测到的粪便中的铅含量低于水禽粪便中的含量（<10 µg / g d.w.）。尽管如此，对于这两个物种，粪便中的铅水平与卟啉排泄呈正相关，而对于紫色鸡胆中，粪卟啉与I / I比例呈正相关，表明对鸟类血红素合成有一些微妙的影响。煤矿泄漏事故发生十年后，仍可检测到这种污染源对鸟类造成的Pb污染，并且可能会持续产生细微影响。
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