Copper and air plants/Tillandsia.

Do not mix them!!!

It seems that copper in its solid form, like wire, is very toxic to Tillandsia. 

 Generally, it does not make much difference what the mounting material is, as long as it is not toxic.

This includes natural toxins such as accumulated salts in ocean driftwood, or phenol/terpene/tannin leachates from some fresh wood/bark – aging and soaking with fresh water usually removes natural toxins.
Do not use treated timber, as these are impregnated with a copper solution (CCA - Copper Chrome Arsenate), which is very toxic to Tillandsias - this also includes the wax treated wood products. Also, avoid painted/stained timbers or materials whereby leachates may be produced. Attempts should be made to maintain the mount as natural as possible.

I have seen the toxicity of copper wire killing plants;

I have removed the copper wire to see if the plants will recover.

I do have a lot of plants hanging on treated laths and poles, but at this stage no signs of any damage.