Geoge-
"Did you just install this? has that white been there for a while or did it just start appearing? "
This was on the brick when I bought the house 3 years ago. The house was built in 1971.
"Is the white material powdery... if you drag you finger across it does some come off? "
No. Not with a fingernail but when I used more force with a small cold chisel, I was able to clean off a little area. Should I just break out the 4" grinder with a masonry wheel?( I hesitate doing that because that'll put fine powder all over everything. My wife would kill me. And she knows where my guns are.)
"Whats on the other side of the wall? "
Just a blank wall in the kitchen. The sink and fridge are on the far side of that room.
I tested one brick as you suggested and some, not all, of the white came off.
Thanks,