A white substance, I'm now worried that this is asbestos, Hope someone can tell me wether it is used in electrical wire, I.E copper based. Please help.
Asbestos was once used as a heat insulator, not electrical. It is doubtful if it is asbestos, as it is not terribly pliable to be inside wiring.
Asbestos has not been used to insulate electrical wire for at about 75 years now. If you are rehabbing a toaster from the 1920's, you might come across it, otherwise the white stuff is probably PVC plastic. If it is fibrous, as in a water heater element, then it is probably rock wool, or more likely: fiberglass - none of which are asbestos.
If the cable is the PVC insulated and sheathed type, the white substance is chalk --- you can eat it. The chalk is used during manufacture to stop the various pieces of PVC from sticking to each other while they are still hot. If it is chalk, it will have a very slightly slimy feeling when rubbed between your fingers. If the cable is of the MIMS or pyrotenax type, the white powder is magnesium oxide --- you can eat it but do not eat it. This cable is the type that has copper on the outside and the inside. The white powder is the insulating material --- it is used instead of PVC. ASBESTOS is no longer used in cable manufacturing but if you are stripping old cable, you could be stripping cable that is insulated with asbestos. Cables that are insulated with asbestos look as if they are covered with a white woven sock (sox). Most asbestos covered cables were used inside stoves (cookers), light fittings, switchboards and other hot places. Ships are wired in asbestos covered cables. It is a criminal offence for a boss to force you to work with asbestos. If you are in any doubt about the identity of the substance, call the local asbestos hotline.
I can't imagine why it ever would have been used in wiring. Also, it hasn't been used for decades, and in the very unlikely event that it was asbestos, it won't have harmed you unless you breathed in the dust.
Asbestos is no longer used for insulating wires today but please take into account that a lot of old appliances and buildings still contain wire covered with asbestos. Great article on asbestos and wires below.
