Instituto Andaluz de Ciencias de la Tierra (IACT), CSIC-UGR, Avda. de las Palmeras 4, E-18100, Armilla, Granada, Spain.
Instituto Andaluz de Ciencias de la Tierra (IACT), CSIC-UGR, Avda. de las Palmeras 4, E-18100, Armilla, Granada, Spain; Departamento de Mineralogía y Petrología, UGR, Avda. Fuentenueva s/n, E-18002 Granada, Spain.
J Trace Elem Med Biol. 2017 Dec;44:339-348. doi: 10.1016/j.jtemb.2017.09.013. Epub 2017 Sep 18.
Chronic metal exposure, e.g. from metal mining, may cause accumulation of metals in soft and hard tissues, and in developing biomineralizations in the human body. Gallstones are biomineralizations formed in the gallbladder which are able to trap trace elements from the bile. Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) was used to analyze gallstone cross-sections to trace the elemental abundances and correlate them with the principal phases constituting gallstones, namely cholesterol, Ca bilirubinate salts, Ca carbonate, and Ca phosphate. Five different types of gallstones (pure, mixed, and composite cholesterol stones, pigment stone, and carbonate stone) were chosen according to a previous classification based on phase characterization by different spectroscopic and microscopic techniques. These data were combined with bulk solution ICP-MS/OES analyses for total elemental concentrations. The results indicated that cholesterol has a zero capacity to retain elements except for Ca. Hence, pure cholesterol stones contained the lowest bulk metal concentrations, and the metals were found in the scarce carbonate and phosphate phases in these calculi. Calcium and trace element concentrations increased in other types of gallstones along with increasing amount of bilirubinate, carbonates and phosphates; pigment stones being the most enriched in metals. Phosphates were the principal carriers of Ca, P, Na, Mg, Mn, Fe, Pb, and Cd, whereas carbonate phases were enriched in Ca, Mg, Na, and Mn in order of decreasing abundance. Bilirubinate on the other hand was enriched in Ca, Cu, Ag, and Ni. The higher trace metal affinities of bilirubinate and phosphate explain the elevated metal concentrations observed in the pigment stones. These results give new insight to the trace metal behavior in the gallstone formation and the metal accumulation in the human body, validating the possible use of these biomineralizations as a proxy for exposure to metal pollution.
慢性金属暴露，例如来自金属开采，可能导致金属在软组织和硬组织中的积累，并在人体中形成生物矿化。胆石是在胆囊中形成的生物矿化，能够捕获胆汁中的微量元素。激光烧蚀-电感耦合等离子体质谱法（LA-ICP-MS）用于分析胆石横截面，以追踪元素丰度，并将其与构成胆石的主要相（即胆固醇、Ca 胆红素盐、Ca 碳酸盐和 Ca 磷酸盐）相关联。根据先前基于不同光谱和显微镜技术对相特征进行的分类，选择了五种不同类型的胆石（纯、混合和复合胆固醇结石、色素结石和碳酸盐结石）。这些数据与总元素浓度的 bulk solution ICP-MS/OES 分析相结合。结果表明，胆固醇除了 Ca 之外没有保留元素的能力。因此，纯胆固醇结石含有最低的金属浓度，并且在这些结石中稀少的碳酸盐和磷酸盐相中发现了金属。随着胆红素、碳酸盐和磷酸盐含量的增加，其他类型的胆石中的钙和微量元素浓度增加；色素结石是金属最丰富的。磷酸盐是 Ca、P、Na、Mg、Mn、Fe、Pb 和 Cd 的主要载体，而碳酸盐相则按丰度递减的顺序富集 Ca、Mg、Na 和 Mn。另一方面，胆红素富集 Ca、Cu、Ag 和 Ni。胆红素和磷酸盐对痕量金属的亲和力较高，解释了在色素结石中观察到的金属浓度升高。这些结果为胆石形成过程中痕量金属的行为以及人体中金属的积累提供了新的见解，验证了这些生物矿化作为金属污染暴露的替代物的可能用途。
