This bin is totally baby safe, provided of course you're watching your baby while they play. Nothing in it is edible, but I consider it totally appropriate for babies to play with. It's even great for honing fine motor skills!
For the base material, I actually used three different materials. They were all blue though to represent the ocean. Pom poms of different sizes/textures/shades, cut up plastic straws, and hair rollers. You probably have most of this stuff around the house, could easily obtain it for cheap, or can substitute something else for it.
Then I added toy characters from Finding Nemo that can be purchased at Dollar Tree. It's adorable and sure to delight!