r/AskHistorians has more to say about this: http://www.reddit.com/r/AskHistorians/comments/23o92d/on_cosmos_neil_degrassetyson_said_some_historians/
Turns out, when your entire plumbing system and all your aqueduct pipes are made of lead, your water probably contains more lead than is strictly safe.
Why do you think they call it "plumbing?"
[R]esearchers don't think the locals were getting high enough doses to cause the kind of brain damage that would lead to, for instance, an increase in crime.
I've always been suspicious of the theory that lead pipes were the cause of Rome's fall, or even a contributing factor. Infighting, inbreeding, corruption, consolidation of wealth, and the difficulty of maintaining a sprawling empire always seemed like much more plausible reasons. There isn't any one factor, of course, but even if lead poisoning played a role it's way down on the list.
Although I also understand the Roman upper classes sprinkled powdered lead on their food to sweeten it. That would do a lot more damage than lead pipes.
Wow. Good point. I'd never considered that.
It's so warming to know that the 20th century was able to provide a much more effective lead delivery system than the 1st.
I'm skeptical for a different reason. Lead is highly electronegative, which means it is extremely difficult to corrode... which is why it makes great pipes.
Have you listened to the History of Rome podcast? The politics, alone, provided plenty of opportunity for falling.
But what drove the politics?
I don't think my little take on the lead-crime link gets enough attention. If we believe that the crime boom was due to lead exposure, then we also need to consider the impact that lead had on a range of asshole behavior that didn't show up in crime statistics.
Lead made people violence-prone assholes, but not all violence-prone assholes are convicted criminals. They're just violence-prone assholes we have to deal with in our daily lives. Some of them are probably in charge of important things.
If you listen to the podcast, it was what drives politics everywhere -- power, corruption, burdens of history, class warfare, etc. All perfectly explainable without lead.
Also, timing. The image from the article shows something from Trajan, who ruled during what is widely considered the Empire's height; it didn't come apart until centuries later. You could maybe argue lead had something to do with violence and politics, but then Rome had lots of that during their rise to power, and it's not like contemporaries – from Greeks and Carthaginians to Persians and Germans – were so different. The correlation just doesn't seem to be there.
If I'm understanding you correctly, you probably mean the 19th century was able to provide amuch more effective lead delivery system.
I think we've had this discussion before.
I think that, if we're going to say something 'caused' or even 'contributed' to the collapse of the western Roman Empire, it shouldn't be constant going back to the Roman Republic, it should be something which had worsened since the Roman Republic. I think we can say that soil depletion had worsened, and we can debate whether civil war had worsened, but it seems unlikely that lead poisoning had worsened unless the Romans were using more lead pipes, or the Roman ruling class were coming from areas with more soft water and less hard water, or the Roman ruling class were heating more acidic wine in more lead ware.
I vaguely recall one of the Roman civil engineers, either Vitruvius or Frontinus, suggesting ceramic water pipes in preference to lead ones because of the symptoms of lead workers.
Aha … that's a bit too quick for my exquisite tastes. I prefer it to come slowly, over a lifetime of breathing vehicular emissions.
Why, you need a good clip round the ear off the Invisible Hand for positing such nonsense! That could never happen! Look around you, for goodness' sake! Nope, definitely lead.
They had all of those things from day one, but managed to work through them for hundreds of years, through conspiracy and civil war. But at some point they ceased to have the wherewithal to work through them.
As have we. But in the last decade we've seen parts of our lead-contaminated leadership doing things like starting wars over religious fantasies and threatening secession over the putative "loss of freedoms" that they can never quite enumerate or explain when pressed.
You could look at the 19th as proof-of-concept.
Spoken like a true biker.