Copper chloride, copper acetate, both are green. There will be the occasional free chlorine molecule present from when the PVC was made which will react with copper, though PVC is actually quite stable. More importantly, the plasticiser used in the PVC to keep it flexible will also leach out and degrade. Longer term I would favour the latter as they are often phthalates with a pair of hydrocarbon chains. Although several homologues are used, they all exhibit the same basic chemical reactivity.