Studies Link Lead and Brain Aging

The notion that dementia must be understood from a lifespan perspective rather than as an end-of-life condition is beginning to gain traction. There is mounting evidence that lead exposure in childhood, and even before birth, may have developmental programming effects that contribute to increased risk for brain aging later in life.

A 2005 study led by Riyaz Basha and colleagues demonstrated an Alzheimer's-like pathology in older rats after early-life exposure to lead. A follow-up study in 2007 study by Jinfang Wu and colleagues substantiated the evidence for a developmental origin for brain aging using monkey models. There is growing evidence that mercury and pesticide exposure in early life may also predispose individuals to greater risk of dementia.

This evidence is emerging with a troubling backdrop of American toy manufacturers selling toxic, lead-laced toys from China. Public concern is high enough that both Democratic and Republican presidential candidates directly addressed the toy scandal during the 2008 primary debate season.Prevention tips and further information can be found on the web sites of the US Environmental Protection Agency and the Centers for Disease Control and Prevention.

We need to invest resources not just in finding curative agents for late-life dementia, but in better understanding the effects that the myriad toxins in our environment have on us as we age, and in protecting ourselves -- especially children -- from their damaging effects. Instead of simply focusing on dementia as an end-of-life condition, we urgently require a more "ecological" approach that considers the range of insults to the brain over the course of a lifetime.