That is because it takes a lot for them to be critical, it is rare. I will, for example, check with our lab to find out what the ranges are some time in the next couple of days just to give you an idea but again the methods are analyzer dependent and will vary. I am coming back from vacation so I need a day or two to get caught up on some things. However, I can say for certain, at 10% high, you are nowhere near critical range.

B12 is a water soluble vitamin that is easily eliminated from our bodies; it fluctuates so much that one value it nothing to panic over unless it is too low. Not having enough is much more of a concern and why you are finding more information about this than what happens if too high. The body is more tolerant of this than too low. We cannot function without it.

I don't know the critical end off the top of my head as not seen but rarely, but will check.