Potent synthetic opiate furanyl fentanyl tied to 10 recent deaths in Milwaukee County

Furanyl fentanyl, a powerful synthetic opiate similar to heroin, was found in 10 recent drug-related deaths in Milwaukee County, the medical examiner's office announced.

The substance is an analog, or variation, of fentanyl that can be legally prescribed by a doctor but can be 40 to 50 times more powerful than heroin and can be extremely deadly.

Furanyl fentanyl was first identified in Milwaukee County last year, but it's possible it has shown up before without detection. The county's toxicology lab began routinely screening for that variation last year, said Sara Schreiber, the lab's forensic technical director.

RELATED:  Soaring drug deaths bring search for answers

The lab first saw fentanyl, then a rise in acetyl fentanyl and now more furanyl fentanyl, she said.

"Generally, it's hard to keep up because things are always changing," she said. "The trends are changing. This seems to be the one that's hot right now."

Furanyl fentanyl began cropping up more frequently in the U.S. after China banned more than 100 synthetic drugs, including acetyl fentanyl, in the fall of 2015. Federal authorities added it as a Schedule 1 drug last year after at least 128 deaths were tied to it nationwide. Experts believe that fentanyl produced in Chinese labs is fueling its abuse in the United States and other countries.

The Milwaukee County medical examiner's office released the statistics in the wake of news reports that China added four narcotics — furanyl fentanyl, acryl fentanyl, valeryl fentanyl and carfentanil — to a controlled-substances list. Carfentanil, a drug used to sedate elephants, was linked to a wave of drug deaths last year in Cincinnati, Ohio.

The county data showed 95 deaths involving fentanyl in 2016, more than tripling the number of cases from 2015. Of the 340 confirmed drug-related deaths in 2016, about 42% — 145 — involved heroin.  Lab results are still pending for several drug-related deaths from last year.

And the pace of drug-involved deaths has not slowed so far in 2017.

"We're averaging more than one a day for the first six weeks of the year," Schreiber said. "We'll surpass 440 drug-related deaths this year if this pace continues."