I'm not certain they're correct there, as various studies seem to quote different numbers. Either way, I'm not sure rats are so much more efficient that it would matter: e.g. if the half-life in rats was a few tens of minutes vs the hour or so half-life in humans, would that make the difference between no toxicity and toxicity? Still, I haven't seen other people report vision loss, so maybe the point is moot anyway.

Although, it doesn't preclude some kind of uncommon impairment to formate metabolism, which would explain why it doesn't happen to other people.