Greater Kopmakia wrote:For some reason I'm thinking of some minor legislation capable of regulating the soda and soft drink industry,
If you are thinking of a specific kind of (not interested in checking the link) legislation to prevent some specific kind of food industry "wrong", then I suggest looking at real world, whether there is a specific law for such a thing, or if it is caught within the general legislation for foods and drinks. The WA already has resolutions about food/drink safety (and unless it got repealed or I misremember it passing in the first place, labeling), so I would think that soft drinks would be included in that.
Also consider whether the problem you wanted to address is a very rare occurrence (like, say, using water from a specific spring) or an industry-wide issue. Only really industry-wide issues should get addressed by WA laws, as they have real international legislational value.