The problem, as I see it, is one of a questionable food supply or at least a contamination issue, in which case, each person should decide what matters to them, and is how this particular problem is solved in the micro, which in aggregate, does lessen the macro aspect. I'm thinking of cases like cigarettes and alcohol.
However, where this falls apart is that consumers don't always have that info, and even if we slap warnings on things, it doesn't usually help unless there is a very clear line of causality and effect.
For instance, the prop 65 warnings[0], which are essentially useless.
Either way, I do think that individual choice is the first line of defense for issues like this.
[0] https://en.m.wikipedia.org/wiki/California_Proposition_65_(1...