Experts say this new opioid cocktail is a combination of three drugs, each individually more powerful than heroin.

It’s called “gray death” and apparently for good reason.

This dangerous opioid cocktail is responsible for a spate of fatal overdoses in the United States, and its potency has authorities worried.

Named for its ashy color, the drug looks like dry concrete mix. It can also appear in chunks or rocks.

Authorities in states such as Indiana, Ohio, Georgia, and Alabama have reported the drug turning up recently.

Georgia alone has had 17 overdoses related to it, as well as at least 50 incidences involving the drug in the past four months.

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Despite its relatively uniform visual description, “gray death” isn’t just one drug.

The exact combination of substances that make up the drug appears to vary widely, but powerful painkillers like fentanyl and carfentanil are common, as well as the less well-known designer drug U-47700.

Each of the three drugs are already stronger than heroin, and a combination of any of them is incredibly risky for users.

“Gray death is one of the scariest combinations that I have ever seen in nearly 20 years of forensic chemistry drug analysis,” Deneen Kilcrease, at the Georgia Bureau of Investigation, told the Associated Press.

Fentanyl, the most well-known component of gray death, is a synthetic opioid that was first synthesized in 1960.

It has played a prominent role in North America’s current opioid epidemic. Fentanyl and other synthetic opioids were responsible for nearly 10,000 deaths in the United States alone in 2015 — an increase of more than 70 percent, according to the Centers for Disease Control and Prevention (CDC).

The less common carfentanil is primarily used as a sedative for elephants and other large animals.

U-47700, another powerful synthetic opioid, gained significant public attention when it was discovered in the rock star Prince’s bloodstream along with several other opioids, including fentanyl, at the time of the musician’s death.

The allure of fentanyl and other synthetic opioids for drug traffickers lies in their strength.

Fentanyl is 50 to 100 times more potent than morphine. And carfentanil dwarfs that, being 10,000 times more potent than morphine.

“Drug traffickers can move a high quantity or high volume of the product in a fairly small package,” Dr. Seonaid Nolan, a clinical scientist in addiction medication at the University of British Columbia, told Healthline.

Traditional opiates like morphine and heroin are derived from the poppy plant. However, synthetic opioids can be produced entirely from chemical precursors.

Without having to rely on the poppy plant makes production of synthetic opioids much simpler.

“You can manufacture it in a lab,” said Nolan.

As the number of deaths caused by synthetic opioids rises, the federal Drug Enforcement Administration (DEA) and other agencies have begun to point fingers at foreign importers of the drugs.

They have explicitly named China as potentially the biggest producer — an accusation the Chinese government has denied.

The potency of drugs like fentanyl and its analogs allows drug syndicates to ship less physical product across the border, making searches and seizures that much more difficult for customs and other agencies.

In many cases, the drugs are shipped directly to users through the postal system.

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When domestic drug dealers acquire the opioids, they may not know how strong the batch is.

In addition, because the drugs are created in unregulated labs, the potency can change from one shipment to the next.

“Because it’s so potent, a small misstep in the preparation of the drug can lead to lethal consequences,” said Nolan.

A recent incident in Ohio made national news when a police officer suffered an overdose caused by fentanyl after the substance came into contact with his hands when he attempted to brush some of the powder off his uniform.

In scientific terms, what makes fentanyl and its analogs dangerous is lipid solubility. In other words, how readily the chemical can pass through fatty tissues in the body.

Fentanyl’s high lipid solubility makes it a useful pain reliever because it can be used in a variety of slow-release systems through the skin: patches applied to the body, or lollipops dissolved in a patient’s mouth without having to be digested in the stomach.

Francesco Leri, PhD, a professor at the University of Guelph who studies behavioral pharmacology and neuroscience, told Healthline that lipid solubility makes a huge difference when it comes to the safety of opioids.

“You need smaller and smaller amounts because [these drugs] don’t get metabolized. They go straight to the brain,” he said.

In the case of the officer in Ohio, the fentanyl was able to pass into his body through the tissues on his hand.

“[These drugs] are very fast acting and produce profound depression of respiration and other central nervous system functions leading to many deaths,” Edward Bilsky, PhD, chief academic officer, and professor of Biomedical Sciences at Pacific Northwest University, told Healthline. “First responders and others around the victim need to be careful due to secondary exposure.”

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What all three experts contacted by Healthline agreed on was the need for more widespread availability of the drug naloxone — often referred to by its trade name, Narcan — in the face of rising overdoses and opioid-related fatalities.

Naloxone is used to reverse the effects of an opioid overdose, hence its nickname as a “save shot” or “rescue shot.”

It does not prevent overdose.

Naloxone works by binding to the same receptors as opioids in the brain and actually dislodges opiate molecules — stopping or reversing the physical symptoms of an overdose, namely respiratory depression.

However, the drug is only available via prescription, and laws regulating it vary from state to state. Currently 47 states and the District of Columbia have laws regulating naloxone prescriptions by medical professionals.

“The controversy,” said Bilsky, “in some states and communities is: Do we allow an antidote like naloxone to be widely distributed to nonmedical personnel? It is an amazing drug that can save lives.”

“If everyone was equipped with a naloxone kit we could certainly reduce the risk for mortality associated with these analogues within the illicit drug market,” said Nolan.

Leri argues that even more than just naloxone usage, the United States and Canada need to reevaluate addiction, “dissociating drug use from crime.”

“Trying to curb illicit transportation of substances that are extremely powerful, and you can fit them in a little bottle and essentially sell it to thousands of people. How do you prevent that?” he said.