Disease Proof

Earlier this month we learned that exposing monkeys—a close relative of ours—to lead ups their risk of developing Alzheimer's disease later on. The NewScientist was on it:

Monkeys exposed to the heavy metal during infancy may be predisposed to develop the equivalent of Alzheimer's disease.


"We're not saying that lead exposure causes Alzheimer's disease, but it's a risk factor," says Nasser Zawia of the University of Rhode Island in Kingston, whose team discovered the link.

Zawia's team fed baby monkeys infant formula milk laced with low levels of lead, then followed their progress until the age of 23. While the adult monkeys did not show symptoms of Alzheimer's per se, post-mortem analyses of their brains showed that the lead-fed monkeys had plaques and other abnormalities identical to those found in the brains of people with Alzheimer's.

Maybe there’s some proof in this pudding, because new research has linked lead to aging in older brains. Malcolm Ritter of the Associated Press is on it:

That's the provocative idea emerging from some recent studies, part of a broader area of new research that suggests some pollutants can cause harm that shows up only years after someone is exposed.


The new work suggests long-ago lead exposure can make an aging person's brain work as if it's five years older than it really is. If that's verified by more research, it means that sharp cuts in environmental lead levels more than 20 years ago didn't stop its widespread effects.

"We're trying to offer a caution that a portion of what has been called normal aging might in fact be due to ubiquitous environmental exposures like lead," says Dr. Brian Schwartz of Johns Hopkins University.

"The fact that it's happening with lead is the first proof of principle that it's possible," said Schwartz, a leader in the study of lead's delayed effects. Other pollutants like mercury and pesticides may do the same thing, he said.

Alright, even without this news, we know lead is bad news. So, what can we make of all this? Well, let’s start with the kids. Dr. Fuhrman explains:

We must be careful not to expose our children to chemical cleaners, insecticides, and weed killers on our lawns. Chemicals used in pressure-treated wood used to build lawn furniture, decks, fences, and swing sets have also been shown to place children at risk. When young children are around, we must be vigilant to maintain a chemical-free environment.

And maybe when they get older they can protect themselves, then their children and hopefully, this heightened awareness will nip the whole problem in the bud.