The wikipedia article on Heavy water has some interesting comments to some of your later questions. In particular, it seems that high levels of deuterated wate

The wikipedia article on Heavy water has some interesting comments to some of your later questions. In particular, it seems that high levels of deuterated water inhibits formation of the mitotic spindle, thereby preventing cell division. http://en.wikipedia.org/wiki/Heavy_water http://en.wikipedia.org/wiki/Heavy_water