Hi there,
You are right on the money with this. and I have to say that we really could be sisters because "I drink water all through the day and night, when I'm not drinking coffee". That line is a page out of my playbook!

Anyway, yes. The gunk that builds up in the moving parts of water bottle lids is, for lack of a better term, gross. I go back and forth between not purchasing bottle water out of fear of environmental damage and not using permanent water bottles with lids out of fear of damaging myself. There seems to be and up and down for both sides of the debate. I tend to err on the side using permanent containers. I like ones that are deconstructible and can be run through a dishwasher, then dried out and re-assembled. Another option has been to soak the desconstructed lid parts in a weak bleach solution followed by rinsing and drying. I've not been killed off as yet so continue to do this.