Lead Exposure May Speed Mental Decline

Mental decline is widely considered an unavoidable aspect of aging, but a slew of recent studies link reduced functioning in the elderly to past lead exposure, the AP reports. Common pollutants aren't singlehandedly responsible for memory loss or tremors. But breathing or ingesting lead, pesticides, or mercury early in life can trigger these symptoms of old age prematurely.

Lead is the easiest substance to track because levels of exposure over time can be measured in permanent deposits in the shinbone. One study found that patients with high lead levels mentally decline 2 to 6 years faster than those with less exposure. But with lead restrictions now firmly in place, "Kids who grew up in the 21st century have a lot less to worry about," said one scientist. (More lead stories.)