Mora Miguel A
US Geological Survey, Columbia Environmental Research Center, c/o Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, TX 77843-2258, USA.
Environ Pollut. 2003;125(3):393-400. doi: 10.1016/s0269-7491(03)00108-8.
Concentrations of inorganic elements were determined in eggs of passerine birds including the endangered southwestern willow flycatcher (Empidonax traillii extimus) from four regions in Arizona. The main aim of the study was to determine the distribution of metals in egg contents and eggshells, with emphasis on the deposition of Sr in eggshells. Seventy eggs of 11 passerine species were collected at four nesting locations during 2000. Aluminum, Ba, Cr, Cu, Mn, Se, Sr, and Zn, were detected primarily in egg contents of all bird species. Arsenic, Ni, Pb, and V were detected primarily in eggshells. A proportion of most inorganic elements accumulated in the eggshell. Concentrations of Ba, Cu, Mn, Se, Sr, and Zn in egg contents and As, Ba, Cu, and V in eggshells of yellow-breasted chats (Icteria virens) were similar among locations. However, concentrations of Mn, Ni, Sr, and Zn in eggshells were significant different among locations. Except for Cu, Mn, Se, and Zn, concentrations of inorganic elements were 2-35 times greater in eggshells than in eggs. Most concentrations of metals and metalloids in eggs and eggshells of all the bird species were below levels known to affect reproduction or that have other deleterious effects. However, I found somewhat elevated concentrations of Sr in eggshells (highest MEAN=1505 microg/g dw, n=3) of yellow-breasted chats and willow flycatchers, and in egg contents of yellow warblers (Dendroica petechia) and song sparrows (Melospiza melodia). Whether current observed concentrations of Sr in eggshells are affecting nesting birds in Arizona remains to be determined. Strontium and other metals could be associated with lower hatching success in some areas. This study shows that a proportion of many inorganic elements accumulates in the eggshell and that the potential effects on the proper structure and functioning of the eggshell should not be ignored.
测定了亚利桑那州四个地区包括濒危的西南柳莺（Empidonax traillii extimus）在内的雀形目鸟类卵中的无机元素浓度。该研究的主要目的是确定金属在卵内容物和蛋壳中的分布，重点是蛋壳中锶的沉积。2000年期间，在四个筑巢地点收集了11种雀形目鸟类的70枚卵。铝、钡、铬、铜、锰、硒、锶和锌主要在所有鸟类的卵内容物中被检测到。砷、镍、铅和钒主要在蛋壳中被检测到。大多数无机元素有一部分积累在蛋壳中。黄胸鹟（Icteria virens）卵内容物中的钡、铜、锰、硒、锶和锌以及蛋壳中的砷、钡、铜和钒的浓度在不同地点之间相似。然而，蛋壳中锰、镍、锶和锌的浓度在不同地点之间存在显著差异。除了铜、锰、硒和锌外，蛋壳中无机元素的浓度比卵中的高2至35倍。所有鸟类卵和蛋壳中大多数金属和类金属的浓度低于已知会影响繁殖或有其他有害影响的水平。然而，我发现黄胸鹟和柳莺蛋壳中的锶浓度有所升高（最高平均值=1505微克/克干重，n = 3），以及黄腰林莺（Dendroica petechia）和歌带鹀（Melospiza melodia）卵内容物中的锶浓度有所升高。目前在亚利桑那州观察到的蛋壳中锶浓度是否正在影响筑巢鸟类仍有待确定。锶和其他金属可能与某些地区较低的孵化成功率有关。这项研究表明，许多无机元素有一部分积累在蛋壳中，对蛋壳正常结构和功能的潜在影响不应被忽视。
