Last year, researchers sequenced the genome of famed composer Ludwig van Beethoven for the first time, based on authenticated locks of hair. The same team has now analyzed two of the locks for toxic substances and found extremely high levels of lead, as well as arsenic and mercury, according to a recent letter published in the journal Clinical Chemistry.

“It definitely shows Beethoven was exposed to high concentrations of lead,” Paul Janetto, co-author and director of the Mayo Clinic's Department of Laboratory Medicine and Pathology, told The New York Times. “These are the highest values in hair I’ve ever seen. We get samples from around the world, and these values are an order of magnitude higher.” That said, the authors concluded that the lead exposure was not sufficient to actually kill the composer, although Beethoven very likely did suffer adverse health effects because of it.

As previously reported, Beethoven was plagued throughout his life by myriad health problems. The composer began losing his hearing in his mid- to late 20s, experiencing tinnitus and the loss of high-tone frequencies in particular. He claimed the onset began with a fit in 1798 induced by a quarrel with a singer. By his mid-40s, he was functionally deaf and unable to perform public concerts, although he could still compose music.

Beethoven also had lifelong chronic gastric ailments, including persistent abdominal pains and prolonged stretches of diarrhea. By 1821, the composer showed signs of liver disease, marked by the first of two severe attacks of jaundice. These issues certainly affected his career and emotional state, so much so that Beethoven requested—via a letter addressed to his brothers—that his favorite physician examine his body after his death to determine the cause of all his suffering.

By December 1826, Beethoven was quite ill, suffering from a second bout of jaundice and swollen limbs, fever, dropsy, and labored breathing. His doctor performed several operations to remove excess fluid from the composer's abdomen. On March 24, 1827, he purportedly said to visitors, "Plaudite, amici, comoedia finita est" ("Applaud, friends, the comedy is over"). Two days later, he died. According to his good friend Anselm Hüttenbrenner, who was present, lightning and a loud clap of thunder briefly woke Beethoven, who "opened his eyes, lifted his right hand and looked up for several seconds with his fist clenched... not another breath, not a heartbeat more."

An autopsy identified severe liver damage (evidence of cirrhosis) as the likely cause of death and significant dilation of the auditory nerve. But what caused that liver damage or his hearing loss—or his chronic stomach complaints, for that matter? Medical detectives have been debating possible causes for nearly two centuries, drawing on the composer's letters, diaries, and physicians' notes for evidence, as well as reports on skeletal remains from when his body was exhumed in 1863 and 1888. But no general consensus emerged.