That kind of goes along with anything being toxic in large enough quantites, though. I thought it meant that at normal quantities it was toxic.

Thanks,

Michelle

>Sure, it'll kill you dead if you breath enough in.
>
>Oxygen is also extremely toxic as well. Too much of that and you'll burn up - literally if you get a spark.
>
>I think we breath in something like 65% hydrogen, the rest mostly oxygen and some trace stuff.