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Concentraciones de mercurio y metabolismo en lactantes que reciben vacunas que contienen tiomersal: un estudio
Michael E Pichichero1, Elsa Cernichiari, Joseph Lopreiato
1Department of Microbiology/Immunology, University of Rochester, Rochester, New York, NY, USA. michael_pichichero@urmc.rochester.edu
Lancet (London, England)
|December 14, 2002
Resumen
El tiomersal en las vacunas infantiles no eleva los niveles de mercurio en la sangre. El etilmercurio se elimina rápidamente a través de las heces, con una vida media en la sangre de 7 días, lo que indica la seguridad en la inmunización pediátrica.
Área de la Ciencia:
- Toxicología pediátrica.
- Investigación sobre la seguridad de las vacunas.
- Salud ambiental Salud ambiental es la salud del medio ambiente.
Sus antecedentes:
- El tiomersal, un conservante que contiene etilmercurio, se utiliza en las vacunas de rutina para bebés.
- Existen datos limitados sobre las concentraciones sanguíneas de mercurio y el metabolismo del etilmercurio en los bebés después de la vacunación.
Objetivo del estudio:
- Para medir las concentraciones de mercurio en la sangre, la orina y las heces de los bebés después de recibir vacunas que contienen tiomersal.
- Para evaluar el impacto del tiomersal en los niveles de mercurio en los bebés.
Principales métodos:
- Se estudiaron 40 bebés que recibieron vacunas que contenían tiomersal y 21 controles que recibieron vacunas sin tiomersal.
- Se recogieron muestras de sangre, orina y heces 3-28 días después de la vacunación.
- El mercurio total medido usando la absorción atómica de vapor frío.
Principales resultados:
- Los niveles de mercurio en sangre de los bebés que recibieron tiomersal estaban dentro de los límites de seguridad.
- Las concentraciones de mercurio fueron bajas en la orina pero altas en las heces de los bebés expuestos.
- La semivida estimada en sangre del etilmercurio fue de 7 días.
Conclusiones:
- El tiomersal administrado por vacuna no parece elevar el mercurio en la sangre infantil por encima de los umbrales de seguridad.
- El etilmercurio se excreta rápidamente en las heces después de la vacunación.
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