(CNN) Carfentanil, a sedative for large animals, was the cause of at least eight overdose deaths in the Cincinnati area, said Hamilton County coroner Dr. Lakshmi Kode Sammarco on Tuesday.

Sammarco added that they are waiting on blood and urine tests from five more overdose deaths which she is confident "will also be due to carfentanil."

The most potent opioid commercially available

Carfentanil is the most potent opioid used commercially, 10,000 times stronger than morphine. It is a version or analogue of fentanyl, the painkiller that most recently made headlines as the cause of the the accidental overdose death of pop star Prince.

Carfentanil is a synthetic opioid and can slow breathing significantly. It's not approved for human use, but is used commercially to sedate large animals, such as elephants. Aslittle as 2 milligrams can knock out an African elephant weighing nearly 2,000-pounds.

to give it a boost and stretch their supply. Dealers are also using it to make counterfeit pills. Between 2013-2014, there were 700 fentanyl related deaths. Officials believe it is helping fuel the opioid and heroin crisis. According to the Drug Enforcement Administration , users might not know they are even taking the drug, as dealers have been cutting heroin with fentanylto give it a boost and stretch their supply. Dealers are also using it to make counterfeit pills. Between 2013-2014, there were 700 fentanyl related deaths. Officials believe it is helping fuel the opioid and heroin crisis.

Ohio has been one of the places hardest hit by the epidemic. According to the Centers for Disease Control and Prevention, in 2014, it had the second-largest number of opioid-related deaths in the country and the fifth-highest rate of overdose.

Between 2013 and 2014, Ohio 's fentanyl submissions to DEA labs by law enforcement increased by 1,043%, while fentanyl-related deaths increased by 526%. In the same time period, prescriptions for fentanyl actually dropped by 7% in the state.

However, Hamilton County Sheriff Jim Neil said they are increasingly seeing just fentanyl or carfentanil cut with heroin. "It's not heroin cut with anything else anymore, it's synthetic [opioids] cut with heroin," he said.

In July, Hamilton County officials issued a public health warning about the drug after seeing 35 overdoses, including six deaths, in a three-day period.

Drug difficult to track

The DEA does not track carfentanil cases separately. Most states flag a handful of fentanyl analogues in postmortem testing, but very few labs across the country are equipped to test for it or have any reference materials to help identify it.

In fact, according to Sammarco, the county was unable to test for carfentanil in her lab until just last week because Hamilton County was unable to get a sample of the drug to compare to the overdosed samples. Sammarco was finally able to gain access to the drug last Tuesday after working with Ohio Senator Rob Portman's office.

Sammarco said that the area has been so devastated by overdoses, their toxicology lab is 290 cases behind.

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Hamilton County Heroin Task Force Director Tom Synan Jr. said it was time for Governor John Kasich to declare a public health emergency to deal with the epidemic.

"We need to realize funding immediately that goes into treatment...We need action, and that action needs to be coming into treatment centers," said Synan.

Sammarco agreed that treatment is key to ending the epidemic.

"These people have a disease and need to be treated, and you have to have empathy for that," said Sammarco. "This has to be a community-wide response, raise the awareness with everybody."

Governor Kasich's office is aware of the gravity of the situation. In a statement, the governor's press secretary Emmalee Kalmbach said "Drug traffickers are finding new ways to introduce powerful synthetic opioids, such as fentanyl, into our communities and the overdoses we are seeing in Cincinnati are very tragic and concerning. That is why we are working with city officials to help strengthen their work around treatment, prevention and recovery resources, and law enforcement and to get Ohio's youth drug prevention program into all Cincinnati schools."

In the 2016-2017 fiscal year alone, the state has allocated more than $6 million to fighting the opioid and heroin epidemic in Hamilton County alone. Last fall, the state invested another $1.5 million dollars to provide prescribers and pharmacists instant access to Ohio's drug monitoring program to help identify possible patterns of narcotic abuse.