I did find one study regarding grapevine uptake of CCA that was done in New Zealand.
The conclusion of the abstract was that no measurable uptake was found in fruit, leaves or rachis (pl) of vines supported with CCA-treated posts during the eight months of the study.
Furthermore, the authors coated CCA-preserved wood posts with a rubber/paint compound and found that this pre-treatment significantly reduced the amount of leachate into the surrounding soils.