RE: Physical properties of isotopes? -- H-2 question

["Franta, Jaroslav" <frantaj@AECL.CA>]

 Ruth, you wrote :

 
The only exception to this that I know of is the the differing atomic weights of the isotopes of hydrogen (H-1, H-2, H-3) can result in slightly different reaction rates. 
 

Would you please, if you can, tell us whether the above fact has any bearing on the toxicity - if any - of heavy water ?
The reason I'm asking is that recently I was told that drinking a glass or two of high-concentration or pure D2O would kill you, due to the toxicity. 

I'm very dubious about this, but haven't seen anything that solidly refutes this notion either (I thought that there wouldn't be any difference, even if every hydrogen atom in our bodies were replaced by a deuteron.... am I mistaken ?  .....maybe somebody, somewhere, has tried raising mice on a heavy-hydrogen diet ??).

 

Thanks

 

Jaro