I'm assuming you're asking about the copper wire, and not the pvc.
As far as I know, there have been no tests for this . Copper does corrrode quite easily. Even stainless steel corrodes under the right conditions. However, the reaction occurs when the dissimilar metals or the corrosive materials
come into contact (carbonate or sodium with steel, brass or copper) with each other.
Although some like to say the sea "air" corrodes metals, this is not wholly true. Particles of sodium from the sea (evaporated or moisture laden) blow this corrosive material onto the metal, and the adverse reaction commences. I cannot imagine how sbx could corrode your wire if it were fully encased in pvc. Even if there were such a reaction, both you and I will be dust for a number of years before it impacts the sq!
Hope this helps.