Is it the companies responsibility to be proactive and change their product before there is a huge issue? What would the damage be financially and psychologically to the companies if their products were proven to help cause cancer? If it isn’t just an ethical responsibility to change, maybe it is in their best interest financially to try to make their product healthy for the consumers, to avoid issues in the long run.There would be major problems if either company had to label their soda as containing something that possibly causes cancer. I don't know how that would effect sales, but it certainly would not be positive. People don't want to be drinking something that could give you cancer. The biggest problem the companies would have would be in trying to rebrand after the ordeal. How do you go about convincing people that your product doesn't cause cancer? It's not as simple as making a commercial that states that. The psychological damage will have already been done.
I do believe that it is a company's ethical decision to change their product so it is not harmful to its consumers. That being said, not all companies do that (I'm looking at you cigarette companies). Regardless of whether a company changes its product for the better to avoid consumer backlash, marketing problems or just because its ethical, I believe it is a good decision. In the long run, it is helping the consumer. I would be more likely to buy from a company I knew was actively not trying to give me cancer.
On a side note, I find it interesting that only California has decided that the caramel coloring could be a carcinogen. What about all the other states? I would assume that, even if it's a possibility, other states would also want to ban that chemical. Why do you think some states don't ban chemicals that are possibly harmful? Why is it that California is the only state that seems concerned with carcinogens?