See I thought about this and this is what I figured at first, but then it occurred to me that lint isn't actually microscopic. Some of it probably is, but I bet that the normal, trappable size lint escapes into the lakes via the sewage system and then degrades into microscopic plastics. Could be wrong but if this is true then filtering at the washer, using a mesh similar to the one for the dryer could be a significant help. If the numbers work of course.