La Bioacumulacion en la Ecologia
06-28-11
Es el proceso de acumulación de sustancias químicas en organismos vivos de forma que estos alcanzan concentraciones más elevadas que las concentraciones en el medio ambiente o en los alimentos. Las sustancias propensas a la bioacumulación alcanzan concentraciones crecientes a medida que se avanza en el nivel trófico en la cadena alimenticia. En función de cada sustancia, esta acumulación puede producirse a partir de fuentes abióticas (suelo, aire, agua), o bióticas (otros organismos vivos). Las principales vías de introducción de una sustancia química en un organismo vivo son la respiratoria, la digestiva y la integumentaria.
La acumulación de hidrocarburos clorados es mayor en tejidos animales ricos en grasas.
Los grandes depredadores marinos, como por ejemplo los tiburones, pueden absorber grandes cantidades de mercurio u otros metales pesados a través de los peces que comen. Se conocen casos de intoxicación masiva por compuestos orgánicos de mercurio en peces, como la tragedia ocurrida en la bahía de Minamata en Japón en 1956 y 1958.
En Argentina se han detectado concentraciones elevadas de metales pesados en tejidos de tiburones de la zona de Bahía Blanca.
Alternativas
– Prohibición del consumo de peces o mariscos en áreas con altas concentraciones de metales pesados o pesticidas.
– Monitoreo constante del nivel de estos compuestos en zonas afectadas por efluentes industriales o por el uso de agroquímicos.
Auburn has excellent players, though, especially running backs Michael Dyer and Onterio McCalebb. But Auburn fans should be happy
if the Tigers are half as good as last year, so that means seven wins.
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