Just that, really.
In the last couple of months I've bought new bedding from both Wayfair and M&S. Both of them arrived with an awful smell and I had an allergic reaction even though we washed them several times.
I know there are some specialist allergy bedding companies but they're really expensive and don't seem to be made of cotton. I'd just like to buy some "normal" cotton bedding that isn't treated with whatever it is they treat it with. I know they sometimes treat new clothes with formaldehyde or something but bed sheets are just getting too much.