Light fittings, strange substance

[Mike]

Anyone got any ideas as to what strange green (almost) liquid would be in my light fittings. I was changing the usual pendant light fittings in my lounge (2, one each end in my 60's built house) for some fancy up-to-date fitments. Wen I took off the old rose pieces they had what looked liked old congealed washing up liquid in them, shich was difficult to actually was off once It was on my hands. Any ideas apart from old congealed washing up liquid? And if it was likely to be that, why?

Cheers

Mike

[Toby]

I have seen this oozing from old T&E cabes in my house (now all replaced, as it think these were old aluminium ones that were "leaking")

Did you notice it on any cables in your fittings?

If not, maybe it was from old cables that have need replaced already?

Toby...

[Mike]

Didn't notice it on any cables just in the fittings. But the cabling is the old red and black stuff :/ And come to think of it, it was on the switches too. But not the ring main sockets......

Ta Mike

[Andrew Mawson]

fittings

Are the cables in conduit? If so it conceivably could be the remains of a lubricant used to pull them through. Though the green hue suggests copper salts from the copper cable itself.

AWEM

[Archon]

I had this in a 70's house wiring. the cable was grey clad, mutistranded T&E, not solid core, and I came to the conclusion the plastic insulation was breaking down releasing some goop. The wire core was corroded also, and that goop I found was acidic and quite irritating to the skin. (Sold the house! Probably needed rewiring). JC

[Mike Clarke]

A google search for green slime cable will give you lots of links. The following is from where it's attributed to NICEIC:

"Unsightly green slime can occur in switch and socket-outlet boxes. It is understood that this phenomenon is most prevalent where pvc cables manufactured between 1965 and 1971 have been used. The green slime, or green goo, is degraded di-isoctyl phthalate and is considered to result from a chemical reaction between the plasticiser of the insulation and the copper conductor in the pvc cable."

Apparently it doesn't reduce the electrical integrity of the conductor or the insulation. It's worth cleaning off when you come across it but avoid getting it on your skin because it's slightly toxic.

[Mike]

Thanks Mike

Strange for me not to Google something as I /always/ do. Normally. That sounds exactly what it is. Saw a thread on Screwfix which explains things sufficiently for my liking, and no worries about having to replace the cables just yet :)

Cheers for all the replies

Mike

[Andrew Gabriel]

Always reminds me of the green slime in Dr.Who's The Green Death...

[The Natural Philosopher]

I think that is most likely: Copper carbonate and silicone grease probably.

[Gib Bogle]

Yet. A bit of a cautionary tale. Today's whizz-bang technology might be tomorrow's unsightly green slime.