When I was 6, I saw a few ants near the refrigerator. I took some salt and poured a small pile by the refrigerator, one by the back door, and one by the front door (because that is where I guessed they came in from outside), and completely forgot about it. A day or two later, I was in my room and heard my mother say, "What?! Where are all these ants coming from?!? What is this?!!"
I went in the kitchen to see a line of ants single-file from the back door straight to the refrigerator. My mother asked me, "What is this, salt? Why?"
I said, "Because they'll eat it and get high-brood-pressure and die." (I guess I'd heard about salt and high blood pressure sometime before age 6, but didn't know about bug spray yet.)