> The concentration is the same in both cases so the adult is getting 30X more.
That should read 15-30 times more, according to your own figures. And then, the baby's mass is about 15-30 times less than the adult, so at the end you are in the same ballpark again, percentagewise.
Yep, but the implication was that the child was getting a megadose. They're not. They would be if they were drinking 15-30X as much water per unit mass. That's not a child, that's a water balloon.
That should read 15-30 times more, according to your own figures. And then, the baby's mass is about 15-30 times less than the adult, so at the end you are in the same ballpark again, percentagewise.