And, at least at the hospital where our baby was born, purple for OB/nursery. Purple scrubs and blankets were part of hospital security, and they kept those suckers under lock and key. I’m a big guy, bigger than the largest paper scrubs they had, so they had to give me a set of their genuine purple scrubs, with strict instructions to return them immediately when the big show was all over.
I work in chemical research. All our lab coats are medium blue. Our old ones were light blue. The last time I wore a white coat was in college. The only reason I can fathom is that blue coats don’t look as dingy as quickly as white.
In the case of most chemicals as well as paints, bleach isn’t going to do much good for the sort of spots we’re dealing with. The spots will only laugh at the launderer. The only way to remove most paint from fabric is to rinse it while the paint is still wet.
I work in dye chemistry. I’ve had to hose stains out of my street clothes with acetone more than once. (amusingly they look fine indoors - the stains only show up when I go outside 
)
When my dad had bypass surgery a few years ago, the cardiac team was decked out in the traditional white - all except for one friendly, nice young surgeon who wore black, head to foot, every day. We wondered about it, but we never did think to simply ask him why. My dad speculated he was part of some religious order. Who knows but the doc himself, I guess?