Superstar guitarist Eddie Van Halen of his eponymous band is reportedly travelling to Germany for treatment for a recurrence throat cancer, although not every doctor buys his theory of the cause.

Eddie was first diagnosed with cancer in 2000 and shortly afterward doctors removed one-third of his tongue.  In 2002 he said he had been declared cancer-free, but now it is believed that Van Halen has been going back and forth between his home in Los Angeles and Germany for the past few years, and that until now radiation therapy has kept the cancer in check.

In a 2015 interview with Billboard magazine, Eddie said:  "I used metal picks - they're brass and copper - which I always held in my mouth, in the exact place where I got the tongue cancer," he said.  "Plus, I basically live in a recording studio that's filled with electromagnetic energy.  So that's one theory."

However, Dr. Tom Micklewright of the UK medical website Push Doctor says that neither copper nor brass as used in metal guitar picks are considered carcinogenic by the International Agency for Research on Cancer (IARC).  And Mr. Van Halen was known to be a heavy cigarette smoker, and that has been linked to at least 15 different cancers in multiple long term studies.

"Copper coils have been used as contraception in the human body for many years without evidence in increased cancer risk," Dr. Micklewright said.  "In contrast, numerous chemicals contained within cigarettes have been conclusively proven to significantly increase cancer risk, and the more likely cause of his throat cancer."