Welcome to the forum, and greetings from across the pond.

If it's just natural bark, I can't see any possible harm. If possible maybe do a little research with the company as to what exactly the product is. Hard to tell exactly what it is, but here's a previous thread. Looks like conifer bark, so you should be ok.

http://forums2.gardenweb.com/forums/load/contain/msg0616252930337.html?6

If the cats are stupid enough to eat bark, what else will they eat? ;)

Barring that type of brain damaged beast, though, I have seen cats totally ignore bark mulch while others think it makes a dandy litter box.

No animal was injured in these experiments.

Dennis

In my experience most healthy cats don't eat things that make them sick, but I have friends who tell me about indoor cats eating poisonous plants and other unhealthy things, like plastic or Christmas tinsel. I understand that willow tree bark contains salicylic acid, the active ingredient in aspirin, which can be deadly to cats. Cocoa shell mulch has made dogs sick or even die when they eat large quantities. But I have not heard of any animal being sickened by pine bark.

You would really have to ask the manufacturer, and even they might not know, if the source plants of the bark had had any insecticides applied to prevent the bark beetle infestations that the US has been having struggles with.

Cats usually stay well away from anything that smells toxic. though.