No. It doesn't pollute the ocean either (duh, fish pee in the ocean)
Surfersvillage Global Surf News, 25 August, 2014 - So does peeing in your wettie, or the ocean for that matter, attract sharks? According to some digging by the by Australian press - No.
Vic Peddemores, senior research scientist, from the New South Wales Department of Fisheries in Australia told The Sydney Morning Herald: “I would have been dead a long time ago — there is no evidence that urine attracts sharks. I have been in the water close to large sharks like a tiger shark and have [p]eed, and it makes no difference.”
National Geographic ran a series of experiments with sharks and divers to debunk several shark-related myths. They placed 2 divers in water, one holding a bottle of urine that slowly seeped into the water and another diver, in a separate area, without any urine: Experiment Result: No reaction from sharks
We couldn’t find peer-reviewed evidence, but it seems that when it comes to peeing in the water, you are probably fine as far as sharks are concerned.