The toilet brush stands for the least pleasant cleaning, and dream books read it as taking on a job no one else wants. It can also reflect feeling stuck with the dirty work.
Has this come up in your dreams before? What was going on in your life then?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.