Since you are more concerned about shrinkage than bleeding, you should wash it all in warm water and dry the heck out of it. Except for batiks, quilt shop fabrics tend to shrink a LOT. (They also bleed.)
I worked in quilt shops for maybe 6 years.
If you wash in the Synthrapol, be sure to wash it again with soap/detergent, because that is pretty toxic. I think someone here posted a statement from the company to the effect that it shouldn't be used on children's items without rewashing.