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Updated: Jun 18, 2026

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Speciation and Bioavailability Measurements of Environmental Plutonium Using Diffusion in Thin Films
Published on: November 9, 2015
Radionucleidos en el lago Mono, California
Resumen
Mono Lake es el lago Mono.
Área de la Ciencia:
- Química del medio ambiente Química del medio ambiente
- La radioquímica es la radioquímica.
- La geoquímica es la geoquímica.
Sus antecedentes:
- Los radioisótopos de la serie de desintegración de uranio y torio que ocurren naturalmente y el plutonio radiactivo exhiben concentraciones elevadas en la columna de agua del lago Mono.
- El lago Mono se caracteriza por tener un ambiente natural alcalino y salino.
Objetivo del estudio:
- Investigar los factores que controlan la solubilidad y distribución de los radioisótopos en el lago Mono.
- Comprender el comportamiento de complejación de los elementos actínidos en aguas alcalinas y salinas.
- Para determinar las tasas de eliminación y liberación de torio de la columna de agua a los sedimentos.
Principales métodos:
- Análisis de las concentraciones de radioisótopos en la columna de agua.
- Evaluación de la complejación del elemento actinuro con los iones carbonato.
- Evaluación de las relaciones de actividad hija/padre para los isótopos de torio, radio y uranio.
Principales resultados:
- Se observaron concentraciones inusualmente altas de radioisótopos de uranio, torio y plutonio en el agua del lago Mono.
- La complejación de carbonato mejora la solubilidad de los elementos actinuros (estados de oxidación IV-VI).
- El estroncio-90 fue eliminado en gran medida de la columna de agua, probablemente por coprecipitación con carbonato de calcio.
- La eliminación de torio a los sedimentos se produce en escalas de tiempo más largas que un mes, con una desorción al agua que requiere menos de unos pocos años.
Conclusiones:
- La complejación del carbonato es un factor clave en la alta solubilidad de los actínidos en el lago Mono.
- Los diferentes mecanismos de eliminación afectan a varios radioisótopos, con el estroncio-90 siendo eliminado de manera eficiente.
- El torio exhibe un tiempo de residencia significativo en los sedimentos, con una cinética de desorción relativamente rápida.
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