Seizures of deadly synthetic opioids such as fentanyl and carfentanil have soared in Minnesota this year, forcing law enforcement agencies to adopt new procedures for collecting evidence, making drug arrests and testing samples at forensic laboratories.

The synthetics are so powerful that, in some cases, scientists at the state Bureau of Criminal Apprehension (BCA) have been told not to handle drug samples without an agent nearby to administer naloxone, an antidote, in case of accidental contact.

Prosecutors are also starting to pursue the first federal case in Minnesota involving distribution of carfentanil, a substance that killed at least a dozen people in the Twin Cities area earlier this year. That investigation has confirmed that several deaths earlier this year did not result from one "bad batch" of opiates and that carfentanil, 100 times stronger than fentanyl, was still in circulation months after the last of 12 confirmed area deaths.

The drugs are so pervasive that authorities have noted, with some surprise, examples of other drugs like methamphetamine and cocaine being tainted with synthetic opioids in recent months.

"It's gotten to the point where we just feel like we've been hit with a tidal wave of cases," said Chief Hennepin County Medical Examiner Andrew Baker, whose lab first sounded the alarm about the emergence of carfentanil in the spate of area deaths this spring.

By midyear, investigations involving fentanyl samples at the BCA had already blown past last year's total, said Superintendent Drew Evans. Cases involving carfentanil also hit a record by June — 25 cases, up from just four last year, Evans said.

This new reality has prompted dramatic efforts by agencies at all levels to protect first responders from substances that can kill even in trace amounts. Some state and local law enforcement agencies have decided to stop testing suspected drug samples at crime scenes, opting to send evidence straight to the BCA for analysis.

Law enforcement agencies like the Hennepin County Sheriff's Office are wearing extra equipment at certain crime scenes and making sure lab technicians don't work alone, following new guidance from the U.S. Drug Enforcement Administration.

A Ramsey County Sheriff's Office spokesman said the agency stopped field testing narcotics within the past year, has instructed investigators to double-bag any powdered substances taken as evidence and to otherwise leave such drugs undisturbed if found at the scene of an overdose or a crime.

Police in Roseville are among the local agencies that now send drugs to the BCA for testing instead of trying to make a presumptive identification on the spot, said Lt. Lorne Rosand. In many cases, Rosand said, police can't arrest a suspect on charges until they get test results back from the BCA lab.

"Gone are the days of [TV actor] Don Johnson licking his middle finger, touching it and going 'cocaine,' " Rosand said. "We never of course did that. ... But now we have to be even more careful. Everyone has to be gloved up and wearing masks if we can."

Over the weekend, Rosand said, Roseville police opted to tow a stolen vehicle they stopped instead of searching it at the scene because syringes were found inside.

"The risk-reward is too much risk," he said.

First federal charges

This spring, Baker's office alerted the DEA that overdose deaths first believed to be from too much heroin were actually linked to carfentanil — a painkiller originally used to treat large animals that can be fatal to humans in minuscule doses.

But if authorities thought the deaths resulted from one rogue batch that temporarily hit the Twin Cities, a new federal case has underlined a stubborn presence of carfentanil in the metro area.

A federal grand jury recently returned an indictment charging John Henry Edmonds with distributing drugs including heroin, carfentanil, furanyl fentanyl and methamphetamine after DEA agents conducted a series of controlled purchases from Edmonds between July 6 and Aug. 22.

The charges mark the first federal case in Minnesota involving distribution of carfentanil. Law enforcement officials expect more charges.

Now authorities at all levels are racing to keep pace with overseas traffickers capable of altering synthetic opioids' chemical structures to stay within the law. Acting U.S. Attorney Gregory Brooker in Minneapolis described keeping up with the rapidly changing drugs a "top priority" of his office.

"We as prosecutors have to be nimble to be able to respond quickly to what is a national public health emergency," Brooker said.

'We have to become involved'

Last week, the U.S. Justice Department also announced the first indictments — including one case in North Dakota — against Chinese nationals that alleged a massive international conspiracy to traffic fentanyl to North America. The lead defendant in the North Dakota case, Jian Zhang, 38, allegedly oversaw the production of synthetic fentanyl in at least four labs in China and advertised and sold fentanyl and supplies used to press the opioid into pills to U.S. customers online.

"It's like a capsule of the whole opioid problem right there," said Kenneth Solek, assistant special agent in charge at the DEA's Twin Cities office.

Assistant Hennepin County Medical Examiner Rebecca Wilcoxon recently won recognition from a national medical examiners' association for her work in helping identify carfentanil as a source of this spring's series of deaths.

Baker said forensic scientists nationally are updating testing procedures almost weekly to better screen for synthetic opioids that can kill at almost untraceable blood concentration levels. He said medical examiners in Hennepin County no longer collect evidence at death scenes, instead asking law enforcement to take materials that may be needed to prosecute.

Minnesota overdose deaths from synthetics are now so numerous — they doubled last year — that it would be impossible for federal authorities to assist in all investigations, Solek said. But, he added, the DEA hopes to introduce more guidance for area law enforcement agencies responding to overdose deaths.

"When it affects the public to a certain extent like carfentanil, we have to become involved," Solek said.