Lead accelerates aging process years after exposure

October 23, 2000

ST. PAUL, MN - Lead exposure on the job can cause progressive declines in memory and learning abilities nearly two decades later, according to a study in the October 24 issue of Neurology, the scientific journal of the American Academy of Neurology.

The study compared 535 former chemical manufacturing employees exposed to lead at work to 118 non-exposed people from the same neighborhoods.

"The effects of the average level of bone lead found in former lead workers was like five more years of aging on the brain," said Brian Schwartz, MD, of Johns Hopkins School of Hygiene and Public Health in Baltimore, MD.

The study participants were followed for four years, undergoing two to four sets of neurological tests with an average of one year between tests. The former workers had an average of 8 years of occupational exposure to lead with an average of 16 years since last working with lead.

The first year of the study, lead levels were determined through blood tests, while follow up visits measured lead levels in bone through a technique called x-ray fluorescence.

"The higher the peak level of lead determined in former lead workers, the greater the decline in brain functions," Schwartz said. "Since these declines were seen long after exposure to lead had stopped, it suggests that the effect of lead on the brain is progressive."

The workers not only had greater declines in test scores due to lead, but also in normal age-related declines in brain functions, Schwartz said.

Significant differences were discovered between the former workers and other participants in tests involved in visual construction, verbal memory and learning, visual memory, planning and organizational ability, and manual dexterity.

"We know there's a decline in brain power as we get older -- generally we call this 'normal aging,'" said Schwartz. "Most of the research has been about how chemicals, like lead, affect kids. This is the first study to explore long-term problems caused by exposure to chemicals as adults. Some of what we have been calling 'normal aging' may in fact be due to past exposures to chemicals or other agents that can affect the central nervous system. This is potentially a very important health problem."
-end-
The American Academy of Neurology, an association of more than 16,000 neurologists and neuroscience professionals, is dedicated to improving patient care through education and research. A neurologist is a medical doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system.

For more information about the American Academy of Neurology, visit its Web site at www.aan.com. For online neurological health and wellness information, visit NeuroVista at www.aan.com/neurovista.

American Academy of Neurology

Related Memory Articles from Brightsurf:

Memory of the Venus flytrap
In a study to be published in Nature Plants, a graduate student Mr.

Memory protein
When UC Santa Barbara materials scientist Omar Saleh and graduate student Ian Morgan sought to understand the mechanical behaviors of disordered proteins in the lab, they expected that after being stretched, one particular model protein would snap back instantaneously, like a rubber band.

Previously claimed memory boosting font 'Sans Forgetica' does not actually boost memory
It was previously claimed that the font Sans Forgetica could enhance people's memory for information, however researchers from the University of Warwick and the University of Waikato, New Zealand, have found after carrying out numerous experiments that the font does not enhance memory.

Memory boost with just one look
HRL Laboratories, LLC, researchers have published results showing that targeted transcranial electrical stimulation during slow-wave sleep can improve metamemories of specific episodes by 20% after only one viewing of the episode, compared to controls.

VR is not suited to visual memory?!
Toyohashi university of technology researcher and a research team at Tokyo Denki University have found that virtual reality (VR) may interfere with visual memory.

The genetic signature of memory
Despite their importance in memory, the human cortex and subcortex display a distinct collection of 'gene signatures.' The work recently published in eNeuro increases our understanding of how the brain creates memories and identifies potential genes for further investigation.

How long does memory last? For shape memory alloys, the longer the better
Scientists captured live action details of the phase transitions of shape memory alloys, giving them a better idea how to improve their properties for applications.

A NEAT discovery about memory
UAB researchers say over expression of NEAT1, an noncoding RNA, appears to diminish the ability of older brains to form memories.

Molecular memory can be used to increase the memory capacity of hard disks
Researchers at the University of Jyväskylä have taken part in an international British-Finnish-Chinese collaboration where the first molecule capable of remembering the direction of a magnetic above liquid nitrogen temperatures has been prepared and characterized.

Memory transferred between snails
Memories can be transferred between organisms by extracting ribonucleic acid (RNA) from a trained animal and injecting it into an untrained animal, as demonstrated in a study of sea snails published in eNeuro.

Read More: Memory News and Memory Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.