One more thing to worry about: fibers from polyester and acrylic are polluting the oceans. See
Laundry Lint Pollutes the World's Oceans - ScienceNOW.
I'm not a big fan of polyester or acrylic fabrics because they attract static unless you treat them with fabric softener, which to me has an unpleasant odor. But I didn't know that their fibers are showing up in sand all over the world!
I guess if you have these fabrics, you should wash them rarely, which means wearing them less, until we find out how much of a threat this is to marine animals and those who eat them. (That includes ourselves.)