I didn't say it invalidated the model. All models are wrong, some are useful.
But what we've discovered is classes of chemicals that cause more damage at small doses, because they interfere with subtler communication pathways in the body such as hormones, and those effects diminish at higher accumulations. There are other categories, like 'no dose is safe', which GP is implying may be the case for this compound, in which case 'the dose is the poison' is a divide by zero error.
You can't assume that the model works just because it worked (or we ignored the data that didn't fit the model) for 450 years. But the original quote is:
"All things are poison, and nothing is without poison; the dosage alone makes it so a thing is not a poison."
In the full quote it's clear we aren't talking about pesticides or arsenic. You can poison yourself with enough iron, or vitamin E. Somewhere along the way it became about how much perchlorate you can have in water before half the fish die.
> But what we've discovered is classes of chemicals that cause more damage at small doses
That's fascinating. Would you please give an example of a chemical whose toxicity decreases with increased dosage?
> In the full quote it's clear we aren't talking about pesticides or arsenic.
"All things" makes it pretty clear what we're talking about. I feel comfortable asserting that both pesticides and arsenic are members of the set of all things, along with vitamins, iron, and perchlorates. I think one might go so far as to say that an organism can be poisoned by any substance its body is capable of absorbing in sufficient quantity. Water poisoning is a fun example. Despite our bodies largely being composed of it, ingest too much and your cells swell up to the point it can cause brain failure. Even the non-reactive noble gasses can cause narcotic effects.
But what we've discovered is classes of chemicals that cause more damage at small doses, because they interfere with subtler communication pathways in the body such as hormones, and those effects diminish at higher accumulations. There are other categories, like 'no dose is safe', which GP is implying may be the case for this compound, in which case 'the dose is the poison' is a divide by zero error.
You can't assume that the model works just because it worked (or we ignored the data that didn't fit the model) for 450 years. But the original quote is:
"All things are poison, and nothing is without poison; the dosage alone makes it so a thing is not a poison."
In the full quote it's clear we aren't talking about pesticides or arsenic. You can poison yourself with enough iron, or vitamin E. Somewhere along the way it became about how much perchlorate you can have in water before half the fish die.