LOS ANGELES, Oct. 22 -- As eight strands of Beethoven's hair have underscored this week, the effects of lead exposure-like sunburns and heartaches-are cumulative and raise risks in the long term.
The soft, bluish metal and humans have crossed paths for thousands of years. Lead mining almost certainly predated the 3000-B.C. dawn of the Bronze Age, as smelting lead requires a lower extraction temperature than does iron. Indeed, the earliest recorded lead mine is reported to have existed in Turkey in 6500 B.C.
Its bright luster, malleability and ability to form compounds with other elements made it attractive for purposes as diverse from shipbuilding to food storage containers.
But as we now know, lead is also a heavy metal toxin that can impair the function of many organs and systems in the body. Once ingested, it travels through the bloodstream and hampers the ability of red blood cells to carry oxygen. It deposits first in the kidneys and then in bones, teeth and hair. It crosses the blood-brain barrier with ease, piggy-backing across on amino acids, the building blocks of proteins. Its half-life in soft tissues averages 40 days; in bones, 20 to 30 years.
Lead poisoning was recognized as early as 2000 B.C. The Greek philosopher Nikander of Colophon, for example, described some of lead poisoning's typical symptoms, such as abdominal colic and pallor, in 250 B.C.
Early societies' widespread use of lead has been a cause of chronic poisonings among populations throughout history. Some historians have even linked the use of lead to the downfall of the Roman Empire. Lead lined many upper-class Roman cooking pots because it transferred heat to food evenly, and engineers used the soft metal for water-supply lines as well. (In fact, the word plumbing is based on the Latin word for lead, plumbum; the word for lead poisoning is plumbism.)
The ancient Egyptians made jewelry from lead as well as dishes -- while Japan's geisha women for centuries used lead-based powder to whiten their faces.
In the 18th and 19th centuries, people who enjoyed port and wine often suffered from lead toxicity illness due to the fact that that preservative and bottling practices utilized lead. The beverages were later found to contain concentrations as high as 300 to 1900 milligrams per liter; modern wine contains roughly one-thousandth to one-ten thousandth such concentrations of lead.
Researchers do not know precisely how Ludwig von Beethoven ingested the high levels of lead. The Health Research Institute scientists who analyzed samples of his hair did tell United Press International that Beethoven's lead exposure came as an adult -- possibly from the mineral water he swam in and drank during his health-seeking stays at spas.
"Beethoven saw physician after physician in search of a cure for his physical ailments," said William J. Walsh, Ph.D and chief scientist at Health Research Institute in Naperville, Ill., outside Chicago. Walsh believes lead poisoning was the primary cause of the miserable life-long illnesses that plagued the musical genius until his death at age 57.
At the time of Beethoven's autopsy, doctors found he apparently suffered from kidney disease, previously undiagnosed. During his lifetime, he reportedly suffered from chronic diarrhea and irritable bowel syndrome, cirrhosis of the liver, chronic pancreatitis, asthma and a generally physically frail and pain-filled life.
Beethoven was also said to be "stone deaf" by 1810, although he wrote the first eight of his nine symphonies between 1800 and 1812, and his ninth 12 years later with no ability to hear whatsoever.
Although Walsh didn't say that lead toxicity caused Beethoven's deafness-his hearing began to seriously deteriorate in 1802 - although medical research has linked lead exposure to hearing loss.
One such study that linked lead exposure to deafness was published in 1997 in the Journal of Occupational Environmental Medicine. It found a statistically significant correlation between blood lead levels and hearing thresholds of lead-exposed workers.
A study last year in the Journal of the American Medical Association reported that Andrew Jackson, the seventh president of the United States, also suffered from lead poisoning. He took a bullet in an 1813 gunfight and the bullet was left in his shoulder for 20 years, leaving its heavy metal ions behind in Jackson's body.
Other recent studies on the effects of lead exposure suggest that the toxin can cause learning disabilities in children, violent behavior in teenagers and mental dysfunction in the elderly.
Walsh, who headed the group of researchers that analyzed Beethoven's hair, has analyzed the hair of hundreds of prisoners and murderers, including the likes of Charles Manson, in whom he found element disruptions.
Walsh became interested in the hair phenomenon after familiarizing himself with the violent prison population. He was puzzled that some of the offenders came from stable families with siblings who grew up to be productive members of society.
Considerable studies in biochemical profiles of delinquent adolescents and violent criminals led him to conclude that the behavioral symptoms were strongly correlated with trace elements in the body.
Lead and cadmium in the hair and copper and zinc in the blood have been found, according to Walsh, to be a contributing cause of violence in those individuals with a biochemical predisposition to disrupted levels of elements.
Today, researchers estimate that blood lead levels and lead poisoning affect nearly 1 million children in the United States. Due to their rapid growth, children are particularly susceptible to the toxic effects. The metal also passes through the blood-brain barrier more easily in children than in adults.
Symptoms of lead toxicity in children include irritability, restlessness, insomnia, lack of appetite, abdominal pain and colicky cramps, headache, muscle and bone pain, behavioral and learning problems at school, hyperactivity, hearing problems and delayed growth. Lower lead levels are reversible if caught in time.
As Beethoven appears to demonstrate, however, adults are not invulnerable to lead exposure. Miners, welders, pipe fitters, foundry workers and even jewelers can accumulate harmful levels-and so can hobbyists.
Those who enjoy making pottery can encounter lead in certain clays and ceramic glazes, while law enforcement personnel can absorb harmful levels simply by practicing regularly at the firing range. People should be wary of using decanters and glassware made of flint glass and older lead crystal.