I developed asthma in my 50's and had to go with allergy shots and inhalers etc. That was when I started quilting
and spending more time (and money)in smaller quilt shops. If I took a class in one,I had to use my inhaler while I was there. After testing, it was formaldehyde that was a trigger. It is used constantly in several forms as a preservative and insect repellant,my doctor said. I always washed my fabric before making clothes, so I continued that with quilting fabric.
Another allergen for one child was the flame retardant on pajamas; I washed twice before he could wear them and then it was okay.He is allergic to many things now that he is grown and his 30's have been full of new allergens.