Need more info about the risks, well I aim to please folks

I've been asked, why didn't the romans die drinking this if its so darned dangerous. Well this is a complex question really, but let me expand upon the threatening warning that I wrote above.

Reason #1 Some did die from drinking these wild fermented beverages

Reason #2 The areas predominate wild yeast is exactly the kind of yeast that is needed to produce good alcoholic beverages, or at least relatively palatable ones. It may not be able to compete with the laboratory grown yeasts we now use, but they worked. In many parts of the world however most of the wild airborne yeasts are not the proper yeasts you want and may produce the wrong kind of alcohol. There are many types of alcohol and humans can only barely handle one, all others are extremely dangerous.

Believe it or not the stagnate rainwater is the safest component of this recipe (other than the honey), while the rainwater would have gathered some rather nasty bugs sitting still for a long time those bugs will not survive the alcohol produced by the fermentation process and in fact in the end, despite there being some risk that some of the wild yeast that grows in the mead might be the kind that produces alcohol that might kill a man, the fact remained it was still safer to drink this mead on average than it was to drink most of the water available, you were statistically less likely to get seriously ill.