As dead as dead can be.
First it killed the Romans,
And now it’s killing me!
As we used to sing at school. Now we know better; the culprit was apparently plumbum, or lead in the vulgar tongue.
Somewhat confusing, not to say confused, article in the Guardian today by Sarah Boseley about study in The Lancet by Dr Philippe Grandjean, from the University of Southern Denmark, and Philip Landrigan, from the Mount Sinai School of Medicine in New York which warn of the potential dangers posed by environmental pollution. The study’s subscription only, so I’ll have to rely on the Guardian’s summary:
The point that Grandjean and his co-author Philip Landrigan, from the Mount Sinai School of Medicine in New York, want to make is that we know very little about the damage we could be doing to our babies’ brains when we expose ourselves and them to modern cleaning fluids, cosmetics, pesticides, glues, plastics and other modern necessities made with potentially hazardous chemicals.
And they believe that there may be already evidence of what these chemicals are doing to us. Neurodevelopmental disorders, for example, appear to be rising, they say, although they acknowledge this is controversial. Many doctors argue that we are simply better at diagnosing them. But certainly more cases of autism are being detected than before. And it is the same with attention deficit disorder, Grandjean and his colleague add. Cerebral palsy is now common.
Are chemicals really causing these things? “I think so, but we don’t know,” says Grandjean. “In this whole group of disorders … the National Academy of Sciences says 3% can be explained by known chemicals, 25% is probably environmental exposures of some kind and probably a genetic predisposition. Of the rest, a lot are unknown and some are inherited.
In this week’s paper, Grandjean and Landrigan have pulled together a list of 200 chemicals in everyday use for which there is evidence of neurotoxicity although the case would not yet stand up in court. They argue that we should not wait for the final proof. It might take 20 years or 50 years to work out what the long-term consequences of exposure to some of these chemicals will be. We should act now, they argue, and put in strict controls for their use to protect babies. If it turns out that the chemicals are harmless after all, then the controls can be lifted, they say. Better safe than sorry.
This application of the precautionary principle is not without its critics; the Guardian quotes
Alan Boobis, a professor in experimental medicine and toxicology at Imperial College London, [who] thinks that some of the evidence lacked rigour. “This is a risk-management issue. In implementing the precautionary principle it is important to take into account all relevant information and not just the potential harm that might result from inaction. For example, what would the consequence (health, economic, societal) be if some of the compounds on the list were banned or severely restricted on the basis of the precautionary principle?”
and yesterday’s Telegraph went even further:
Prof Nigel Brown, the head of medicine and biomedical sciences at the University of London, said that the report verged on scaremongering.
“It is possible that there is a problem,” he said.
“We should be aware of this and we should study the problem, but there is currently not a shred of evidence of a pandemic.”
I’m obviously not qualified to comment on all this, but I was struck by the way lead pollution runs through the Guardian’s article like a theme, partly because it’s a well-known toxin, I suppose, and partly because it provides a useful analogy — even small amounts of lead in the environment have a deleterious effect on children (of which more in a moment) so, by analogy, might not all these other substances so do? I have to say that argument by analogy doesn’t really convince me in matters scientific; people used to think, after all, that malaria was caused by breathing noxious substances in from the atmosphere (hence its name) until they knew better, so, by analogy, might not Profs Grandjean and Landrigan also be similarly mistaken?
I’m not suggesting they are; just that the argument from analogy doesn’t seem to help us much here.
What really surprised me, though, was the Guardian’s announcement that
Lead has been squarely blamed, in some scientific quarters, for the decline of the Roman Empire. Lead was the fabric of the cooking pots, the wine urns, the water pipes, and the plates in Roman times; it was used in makeup; it was even used for its sweet flavouring. It contaminated the food and drink and befuddled the brains of the wealthy ruling classes, the people who could most easily afford classy metalware and were therefore most exposed. Why was Caligula degenerate? Why was Julius Caesar apparently sub-fertile for all his sexual proclivity? (He had only one child.) Because of lead, the theory goes.
I’ve heard this one, as well, and it’s a corker, at least in the way the Guardian uses it. The decline and fall of the Roman Empire has, of course, notoriously been blamed on a lot of things — famously Christianity, by Edward Gibbon — and a moment’s thought should have told Sarah Boseley that it was because of a lot of factors, including political instability, foreign invasion and economic problems.
To point to a single cause is bad enough, but to point to something that could, at most, only have been a secondary cause — all that lead in the environment so damaged people’s judgment that they took rash and ill-considered decisions that contributed to political instability and so on — is utterly preposterous. It’s like saying environmental pollution is responsible for the current debacle in Iraq, since if the American people weren’t so befuddled by environmental toxins they’d never have elected George W Bush.
Preposterous, too, is dragging in Julius Caesar (100 BC to 44 BC) and Gaius Caligula (12 AD to 41 AD) as evidence for the decline of an entity that reached its maximum extension in 117 AD under Trajan and didn’t really run into serious problems until the Crisis of the Third Century. From this, of course, it recovered under Diocletian and lasted for another 100 years in the west (longer in the east). Ah, but if hadn’t been for the lead….
Technorati tags: Lead, Environmental Pollution, Philippe Grandjean, Philip Landrigan, The Lancet