In reply to Mick Ryan - UKC and UKH:
> (In reply to fozmeister)
> [...]
>
> I'll do some more research, contact the major brands and ask why this is so.
Not definitive by any means.... wool allergy is rare and the itch, or prickle factor, isn't an allergic reaction but due to fibre diameter as stated above (and fibre length) and there is variation amongst humans as to the prickle factor threshold.
Here is a good link: www.merrill.org/alabamaalpacas/library/WoolIndustry.pdf
I got in touch with Molly at SmartWool in the US....she sent me this from her phone so excuse the typos etc..
"Some people are indeed very sensitive to wool of any fiber, however in general the lower the micron the softer the feel. A 28 micron is very large and would not typically be used for clothing. For example we would use anything from 17 micron into the low 20s for our clothing depending on the garment. Most of our socks are around the 23 micron range.
In terms of the itch factor, we do work with our wool, including a Smartwash, that helps to reduce itch. I also have very sensitive, but find our clothing, especially the midweight base layers to be incredibly comfortable. I might recommend he try something from our line... And when it comes to Merino, much like a lot of other outdoor gear, you definitely get what you pay for. We use ZQ merino which offers us and our consumers higher quality fiber which results in a higher quality end product.
There is also some info here:
http://eu2.icebreaker.com/Why-Icebreaker-merino/how-does-icebreaker-merino-...
All the best,
Mick