density has everything to with the atomic number, which is why hydrogen and helium are so light...water doesn't have an atomic number because it's a compound molecule, made of different elements bonded together. tungsten and lead have atomic numbers because they are (supposedly) pure. Tungsten can't be more dense than lead, unless something else is going on, like mixing or whatnot. Now, lead is probably worse on the environment if left in the water, than tungsten...but for now, I'll probably just stick to lead and save about 900%. just my opinion