I'm afraid there are no studies that have been conducted on the subject of using non-food-grade wire in cake (that I have ever found, anyway).

However, one can draw some reasonable conclusions.

First, stainless steel is graded according to how pure it is.  That's why there is medical-grade stainless steel (designed to be used in the human body for indefinite periods of time without doing harm) and there are low grades of stainless steel, such as that used in beading/jewelry making and fishing.  One cannot say that all stainless steel is food-safe.  Would you let a surgeon use stainless steel fishing wire in your body to save a few bucks?

Secondly, not long ago there was a recall of floral wire that was sold at Michael's, Hobby Lobby, etc., for containing high levels of lead.  The recall notice - which I personally read with my own eyes - specifically warned against touching this wire because of the risk of lead contamination.  How much lead is okay and how much is toxic when it comes to using wires with lead in food?  Because we do not know, we MUST err on the side of caution and say NO LEAD EXPOSURE is okay.

Speaking to the general public, justifying continuing to do something just because you and/or others have done it for x number of decades is just plain ridiculous.  Ask my dead grandparents how that worked out for them with the issue of smoking cigarettes.

It's a simple enough matter to place wires inside of coffee stirrers or any other method of protecting food from contamination from the wire.  I order orthodontic wire from www.orthostock.com which is medical-grade wire for when I want to stick wire directly into cake.  It shouldn't be a big deal to do the right thing.  :)

I ordered 16, 18, 20, 22, and 24 gauge.  I spoke with the owner before ordering for the first time to confirm that they sizes they go by correspond to the gauge of the wire.  So, part # 40.40.880.00018 is a 14" long 18 gauge wire.  Part # 40.40.880.00020 is a 20 gauge wire.  And so on and so forth. :)

Thanks!

AInteresting cakepro, thanks for taking the time to give such a detailed response. I'm in the UK, and I've never bought wires at a hobby shop, only ever a cake shop, so I can't comment on that.

I was just interested in why there is such a vehement argument about this when there didn't appear to be any actual studies etc. Obviously if wires were recalled for lead levels from hobby shops that's where this comes from. You'd hope they'd have learnt from it and the risk would no longer be there, but clearly without tests no-one would know.

I have no idea if the wires we use over here contain lead. I'd hope that they wouldn't given that they are sold as sugar craft items not as general hobby, which appears to be where the problem arose, but as I said before I always wrap mine anyway so it's not an issue to me.

Thanks for you answer, it was very informative.