I think "toxic" would be a bit extreme. I would think if something is truly toxic (oh my God I'm gonna die!!!) it would have warnings on it, whether it was intended for food stuff or not. I think there have been thousands upon thousands of cakes made in the history of all cakeing with ribbons wrapped around them. When someone can direct me to factual evidence of someone dropping dead after eating cake that had a sliver of ribbon on it...I'll quit using it.
I'm not usually one to jump on the "ick" bandwagon, but most ribbon is manufactured in textile factories which do not have to comply with food safety codes. Factories, especially in third world countries, are notorious for vermin, such as rats, who make their homes there.
I don't like ribbon touching icing for long periods of time for the same reason I don't let my cats on the counter. I know where their feet have been! 
That said, I wouldn't freak out over a cake with ribbon. And I certainly wouldn't freak out anyone else with horror stories and badmouthing someone's cake.
I guess it's like the 5 second rule. I've never heard of anyone dropping dead from eating food that has landed on the floor or ground. But that doesn't mean those people didn't ingest a trace amount of EWWWWWWWW.
Food for thought...
Ewww is right! So I'll pretend I never read your post and continue to line my ribbons blissfully unaware of the Taiwanese-rat pee soaked ribbon that I just put on an $800 cake.
You certainly paint an appetizing picture... bwahahahaha!!!
Diane,
If the dye is bleeding onto the buttercream I would certainly remove the ribbon, scrape off the buttercream and redo it. You don't want to deliver or serve a cake that has black ribbon dye on it.
I would doubt that anyone would get ill from the small amount that would be ingested however I don't think it's good business to sell the cake with the dye on it.
Since joining CC I've made a conscious choice to stop using real ribbon on real cakes (only dummies). I now just make my ribbon out of fondant, one less worry in my opinion.
Ewww is right! So I'll pretend I never read your post and continue to line my ribbons blissfully unaware of the Taiwanese-rat pee soaked ribbon that I just put on an $800 cake.
I snorted Dr Pepper out my nose! IT BURNS!!!
Ewww is right! So I'll pretend I never read your post and continue to line my ribbons blissfully unaware of the Taiwanese-rat pee soaked ribbon that I just put on an $800 cake.
I snorted Dr Pepper out my nose! IT BURNS!!!
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