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La vida útil en la troposfera de los anestésicos halogenados
A C Brown1, C E Canosa-Mas, A D Parr
1Physical Chemistry Laboratory, University of Oxford, UK.
Nature
|October 19, 1989
Resumen
Los anestésicos halogenados como el halotano, el enflurano y el isoflurano tienen una vida útil atmosférica corta. Su reacción con los radicales hidroxilo (OH) evita el agotamiento significativo de la capa de ozono o las contribuciones al calentamiento global.
Área de la Ciencia:
- Química de la atmósfera química de la atmósfera
- Ciencias ambientales Ciencias ambientales.
- Farmacología Farmacología.
Sus antecedentes:
- Los anestésicos halogenados (halotano, enflurano, isoflurano) plantean preocupaciones con respecto al agotamiento de la capa de ozono estratosférica y el calentamiento global.
- El impacto ambiental de estos anestésicos está relacionado con sus vidas atmosféricas.
Objetivo del estudio:
- Para determinar el tiempo de vida atmosférico del halotano, el enflurano y el isoflurano.
- Evaluar su contribución potencial a la pérdida de ozono y al calentamiento global.
Principales métodos:
- Se midieron las velocidades absolutas de reacción del halotano, el enflurano y el isoflurano con los radicales hidroxilo (OH).
- Utilizó un modelo atmosférico unidimensional para calcular las vidas atmosféricas.
Principales resultados:
- Las vidas atmosféricas determinadas de 2, 6 y 5 años para el halotano, el enflurano y el isoflurano, respectivamente.
- Calculado que estos anestésicos contribuyen con una fracción menor (aprox. 5 x 10^-4) para el cloro atmosférico.
Conclusiones:
- El principal sumidero atmosférico para estos anestésicos es la reacción con los radicales OH.
- A pesar de las preocupaciones, su vida atmosférica relativamente corta limita su impacto en el agotamiento de la capa de ozono y el calentamiento global.
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