This is my trusty old Daughtry water bottle/mug. I use it every day. Yes it was some mineral deposits on the top that look really gross but I wash it at least once a week. Sometimes even twice but I just found out it's still gross!
It is seems your water bottle is probably dirtier than a slobbery dog bone! The bottles with a straw are a little better but still not great.
Find out more here. I'm headed to the kitchen.