There is, but banning these substances is a political process not a scientific one. It’s definitely true that this should be done by experts and not politicians.
The thing is that it’s impossible to set up an experiment to show that something is safe. All you can do is collect more evidence that something is not dangerous. This leads to GRAS.
There’s also the additional fact that the dosage makes the poison. There is no substance for which a single molecule can harm you meaningfully.
Roundup is about as toxic as tablesalt. Caffeine is vastly more toxic than that. And Tylenol, well, that simply wouldn’t be approved if it were invented today. The ratio between the therapeutic dose and the lethal dose is too small.
Then there’s tradition and utility.
Plenty of herbal supplements and even foods are quite dangerous but are sold because they always were and they are “natural”.
We can all agree that certain substances don’t belong in food - either because they are useless or there’s strong evidence they’re harmful.
It’s the useful ones for which there is some evidence that they may cause issues when given in extreme doses, but a vast number of substances exhibit that behavior. Caffeine and Tylenol, for example. You do not think of these as poisons, but they are. Caffeine is so dangerous that you have to go through a lot of trouble to get it in its pure form.
The fact is that those supstances are certainly more dangerous than the substances in the article, but people are not clamoring to ban them.
And all this complexity is before people’s individual interests are involved.
This is why when you compare, say, us and eu food regulations you find substances that are on one list and not the other. One is not a superset of the other.
Anyway, these substances are not “toxic” in really any correct usage of the term, and it’s probably very unlikely that a ban will make anyone healthier or happier, despite what you may read about when you Google these substances. Even if you go to the scientific level.
Scientists can have their own agenda. They’re still people. Or they can just be bad scientists. Or they can just be churning out papers as fast as possible to increase their prestige.
It used to be that the top paper that came up (it may still be up in the list) when you search glyphosate and bees was a bad paper. It did correctly conclude that glyphosate killed the bees when they put it in the honey, but they had to put so much in there in order to see any effect at all that the concentration was high enough to actually kill aquatic weeds. Next it wasn’t properly controlled. Do you know what else will kill bees if put it in their honey? Water. And most definitely caffeine. I assure you a very small amount of caffeine in honey will kill a nest.
It’s just a political thing with good optics because who can argue with banning a “toxic” substance.