By John Lauritsen

MINNEAPOLIS (WCCO) — We could get the preliminary results of what caused Prince’s death any day now.

The medical examiner has been working on this since the beloved Minnesota musician died one week ago.

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Sources say prescription painkillers were found on Prince, but otherwise, there have been few answers.

“You want to get the answer right, which is the most important thing,” said Dr. Fred Apple, medical director of clinical laboratories at Hennepin County Medical Center.

Apple’s lab does drug screening and tissue analysis for medical examiners in Minnesota, North Dakota and Wisconsin.

He says autopsies can be done quickly, but it is toxicology that takes time. His lab receives samples from specific parts of the body to test for drugs.

“Urine, blood and liver, and possibly vitreous humor — the fluid from the eyeball,” Apple said.

They screen the samples for drugs and tell the medical examiner what they found. Then a second process starts, where they determine how much of each drug was found.

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“It’s a technology called mass spectrometry,” he said.

If quantity cannot be determined, they have to send the sample to a reference lab in Pennsylvania — and that takes time.

Meanwhile, new samples never stop coming in.

“You have to take in to consideration we get 15 cases a day [from] all those jurisdictions,” Apple said. “Every case [that] comes in gets put in a queue.”

Occasionally, for a high-profile case, they will move a sample to the front of the queue. But even then, they have to be thorough. It is still going to take a few weeks before results are released.

“It’s not as simple as it makes it appear on TV shows, that I can shoot something into an instrument and get a result before the hour show is up,” Apple said.

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Apple says his office can guarantee toxicology results in three weeks, which he says is a better turnaround time than 90 percent of the operations across the country.

John Lauritsen