This seems to be becoming ubiquitous, so watch out for dust mite & antibacterial treatments on bedding - these come under the name of UltraFresh/ Microban & several others - if there's a treatment brand name on the product with no clue as to what's gone in it, request the info. The more we do this, the more manufacturers will realise they can't just dump this stuff on the population unasked.
My recent experience - It seems the brand 'Ultra-Fresh' can be several different substances, one of which is Triclosan. It can also be nano silver/aluminium. Ditto any of the other brand names used to treat duvets/pillows etc.
& not realising what 'Ultra Fresh' was, (the seller refused to say when asked)
I sent a pic of the label to the manufacturer of Ultra-fresh & it transpired the label was a fake - so in fact it could have been treated with just about anything .. or nothing! Amazon made them take it off, but back it came a few weeks later with the term 'Ultra Fresh' removed from the description & "treated to inhibit dutmites and bacteria" up there instead. Myself and several friends have attempted to get a reply from them as to what this has been treated with now, and have been ignored.
If anyone else feels like having a go, at least we might take enough of their time it'll make them think twice about putting up rubbish in future. You can also leave a review (even tho you haven't bought the item), saying the seller refuses to say what it has been treated with. They know me now, so mine are not getting thru.
Amazon are usually pretty good with customer service but they can't keep tracks on their marketplace sellers well, so apart from initially making them take the duvet down, they aren't bothered at all it seems that it's gone up again with bits of description changed, (it is certainly the same item as the link in my buyer account goes straight to it) , or that no one can get replies to questions as to what it is now being treated with, or that the seller removed my original review which warned about the product.
So buyer beware! Neither Triclosan nor silver /aluminium nano particles or any of the other chems used for bedding are going to give you sweet dreams! You'll be absorbing them all night long. We spend too much of our life in bed to mess with this stuff.
For what it's worth I emailed M&S and asked if they treated their duvets with anything at all & they said no, so I will be buying there. However if you are wanting one 6 mo's from now, worth rechecking - this changes all the time.