Lead Link to Alzheimer's Disease?

Jan. 2, 2008 -- Lead poisoning in infancy may make Alzheimer's disease more likely decades later, a new study shows.

Lead poisoning is a well-known danger, especially for young children. Months or years of lead poisoning can stunt children's growth and damage their brain, kidneys, hearing, and mental development.

Early lead poisoning may also tinker with genes in a way that sets the stage for Alzheimer's disease as an adult, according to the new study, which is based on monkeys, not people.

The study included two groups of baby monkeys that drank formula for the first 400 days of their life. One group of monkeys got ordinary, lead-free formula. The scientists added low levels of lead to the other group's formula.

No health problems were seen in the monkeys during the 23-year study.

The scientists checked the monkey's brains at the end of the study. The monkeys that drank the lead-laced formula as babies had higher levels of Alzheimer's-related proteins and more DNA damage than the other monkeys.

Lead poisoning in infancy may have made the monkeys' genes make more of the Alzheimer's-related proteins years later, according to the researchers, who included the University of Rhode Island's Nasser Zawia, PhD.

Their findings appear in The Journal of Neuroscience.