Heavy metals in Beethoven's hair may explain his deafness, study finds

High levels of heavy metals detected in Ludwig van Beethoven's hair reveal that he may have had lead poisoning, possibly contributing to his deafness and other illnesses, a new study finds.

Researchers analyzed DNA in two authenticated locks of the German composer's hair and discovered that they contained alarmingly high concentrations of lead, as well as high levels of arsenic and mercury, according to a study published May 6 in the journal Clinical Chemistry.

For example, one lock contained 380 micrograms of lead per gram of hair, while the second had 258 micrograms per gram of hair. (Normal levels today would be closer to 4 micrograms or less.) His hair also contained 13 times the normal level of arsenic and four times the typical level of mercury.

"These are the highest values in hair I've ever seen," study co-author Paul Jannetto, a pathologist at the Mayo Clinic, told The New York Times. "We get samples from around the world, and these values are an order of magnitude higher."

The high levels of these toxic metals could partly explain why Beethoven experienced a number of illnesses, the study authors noted. He started losing his hearing in his 20s, was completely deaf by his late 40s, had gastrointestinal issues and experienced at least two episodes of jaundice, a symptom of liver disease. 

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While high lead levels are associated with gastrointestinal and liver problems, as well as with decreased hearing, it's unlikely that the levels were high enough to be the "sole cause of death" for the composer, the researchers said. However, his high level of lead exposure "may have contributed to the documented ailments that plagued him most of his life," the researchers wrote in the study. The study authors didn't comment on how higher arsenic and mercury levels would have affected his health. 

An earlier study of Beethoven's hair also found high levels of lead, but this research was later debunked when it was discovered that the locks belonged to an Ashkenazi Jewish woman. However, a recent DNA examination of verified locks of his hair determined that Beethoven, who was born in 1770 and lived to be 56, was infected with hepatitis B and had a high risk of liver disease, which may have contributed to his death. 

There are a few possibilities for what caused Beethoven to have so many contaminants in his system. 

One theory involves his penchant for wine; he often consumed an entire bottle in a single day. It wasn't uncommon during that time for wine producers to include lead acetate in their concoctions as a preservative and sweetener. Back then, glass bottles also contained traces of lead. The "Fifth Symphony" composer also ate a lot of fish caught in the Danube, which was known for containing arsenic and mercury, CNN reported.

In Beethoven's day, it was common for people to take snippets of hair from loved ones or celebrities. Now, this hair is shedding light on the possible causes of Beethoven's illnesses, which he failed to identify during his lifetime.

"We believe this is an important piece of a complex puzzle and will enable historians, physicians and scientists to better understand the medical history of the great composer," the researchers wrote.