Is That Urine on the Wall?

While cleaning the bathroom wall next to the toilet, I cleaned what appeared to be a droplet of urine that was approximately 5.5 ft high. I say appeared as it was the same color as other drops that I clean off that are at or below waist level. I teased my husband about it and he insists that it is physically impossible. I read some forums online that spoke of possibilities due to entry and exit velocity, and he said that if that proved anything then he is sure that at some point in his life he would have had a pee drop hit him in the face. He is 6' tall and stands to pee. He said that he usually likes to aim for the porcelain at the back of the bowl just above the water level. We have lived in the house for 4 years after a heavy smoker. 3 years ago I washed that wall to about 7 feet tall and painted a mural of a palm tree in the middle but other than wiping down the wall with slightly soapy water on a sponge, the white existing paint is still in the background. My husband insists that the droplet I cleaned was from water that he splashed over from the shower and that residual cigarette smoke caused the droplet to be dark yellow. The droplet had a visible drip streak of approximately 4-5 in and was a raindrop sized, hard, slightly shiny, and did have some depth and was not just a soaked in stain. In your professional opinion, which is more likely, that it was a droplet of urine or a smoke stained splash. One final question is if a bathroom was very warm, would urine evaporate and condense higher up on a wall or ceiling. Thank you
- Kristina (age 37)
Carmel Valley, CA USA

Great question. We can answer one part with confidence. If some pee evaporates and re-condenses, only the water part will make it to the new drop. Urea, etc. will be  left behind on the floor. So that wouldn't be the mechanism. 

I have sometimes noticed dried-up non-pee droplets that with a sort of yellowish color, I guess from something that leaches out of wallpaper, and  I guess some sort of leftover cigarette tar could have the same effect. So I lean slightly toward the non-pee explanation. (Maybe Lee will have a different subjective take.) On the other hand, remembering the friend who worked in a fast-food burger franchise where the guys would have contests as to who could stand farther back from the meat bin....

If it happens again, you might try to scrounge some test for urea. According to Wikipedia, diacetyl monoxime is useful for that but may be hard to buy in small enough amounts to be inexpensive enough.

Mike W.

(published on 05/31/2013)