i have relatively mild mcs - i'm allergic to a lot of scents, dyes, perfumes, chemicals, etc. in small doses it's not the end of the world, but it's a huge inconvenience and it's painful and irritating. in large doses it can make it really difficult for me to do anything for the rest of the day thanks to pain, fatigue, etc. i work with and organize with a lot of people with more severe mcs than i have so i'm used to setting up, requesting, and pushing for scent-free space.
one thing most people don't understand is that not everything that has a smell will trigger mcs - most people with mcs have different levels of sensitivity, but even so, things like food normally don't trigger mcs (unless there is some sort of chemical in it). or, for example, the smell of coconut oil (i hate the smell, but it's a great non-toxic alternative to scented moisturizers and massage oils and it usually doesn't trigger a reaction for folks w/mcs). another common misconception is that all "natural" scented products are okay to wear around folks with mcs - for example, essential oils and incense ARE often toxic to us, and even things like lavender can cause reactions for some people.
i get really frustrated sometimes with this and "accommodations" for my other disabilities. it is NOT that hard to use scent-free soap in public restrooms or restrooms at work, church, etc. you may not be able to get people to stop wearing massive amounts of scented body product to a place but exchanging soap in the bathrooms and not using highly scented air fresheners in the building is a good start. and hello - most of the stuff that people with mcs are allergic to - we're allergic to it BECAUSE THE SHIT IS ACTUALLY TOXIC. which means it's probably toxic to you too, you just aren't as sensitive to it (yet). for years i didn't realize i had mcs and i didn't understand why i constantly had allergies until i became friends with other people like me because no one ever talks about how toxic the chemicals we put on our bodies actually are.
i understand the frustration some people have with not wanting to change their personal routine to suit other people, but sometimes when we are in community together i'm like - look, either you want to be in community with me and you care about me or you don't. access needs outrank personal preferences, in my opinion. it's sort of like, with my mobility issues, when i go to an event that's held upstairs and no one bothered to tell me or even give a shit that a disabled person might want to come. recently this happened when my coworkers at a mental health dis org planned a community mental health event they knew i was coming to because i was deeply involved. i got there and there was a huge flight of stairs. it felt like a slap in the face. even with my partner sometimes this is a problem - he is really great about dealing with my physical disabilities but sometimes he still sees dealing with my mcs as him doing me a favor (because he frequently wears men's deodorant, cologne, etc. and it makes me really sick).
i also think people have a responsibility to keep food that causes allergic reactions for others out of a space once that need has been articulated. we had that issue at a meeting recently - we were eating oranges and someone was severely allergic. the oranges got thrown away, moved into the other room, and we all washed our hands and face with unscented dr. bronner's. to me it's just human decency. did i want to eat oranges? yeah. was i upset that i had to stop? was it an inconvenience? not at all. i cared about that person and i wanted them to be able to be in the space.
edited to add...on the upside...femme allergy masks for the win!
http://www.icanbreathe.com/store/page12.html