I've dealt with NORM quite a bit and it's pretty hard to get it in tubing that would be used or sold for structural pipe. My experience from both the production side of O&G and the welding side is vessels are the worse. Tubing or pipe generally has to come from facilities that moved A LOT of production water like swds or water flood fields... stuff like that to get any kind of norm to worry about. Generally that pipe is not in good enough shape to be sold for any thing.
Basically, it's not some thing I would worry about. I'd worry about the quality of tubing after being exposed to h2s, co2, carbonic acid, etc down hole. It won't kill you but it's makes for some crappy pipe in a couple years.