***Article first published by 'The Guardian' on Dec. 11, 2016***

Natasha Butler had never heard of fentanyl until a doctor told her that a single pill had pushed her eldest son to the brink of death – and he wasn’t coming back. “The doctor said fentanyl is 100 times more potent than morphine and 50 times more potent than heroin. I know morphine is really, really powerful. I’m trying to understand. All that in one pill? How did Jerome get that pill?” she asked, her voice dropping to a whisper as the tears came. “Jerome was on a respirator and he was pretty much unresponsive. The doctor told me all his organs had shut down. His brain was swelling, putting pressure on to the spine. They said if he makes it he’ll be a vegetable.”

The last picture of Jerome shows him propped immobile in a hospital bed, eyes closed, sustained only by a clutch of tubes and wires. Natasha took the near impossible decision to let him die.

“I had to remove him from life support. That’s the hardest thing to ever do. I had him at 15 so we grew together. He was 28 when he died,” she said. “I had to let him die but after that I needed some answers. What is fentanyl and how did he get it?”

That was a question asked across Sacramento after Jerome and 52 other people in and around California’s capital overdosed on the extremely powerful synthetic opioid, usually only used by hospitals to treat patients in the later stages of cancer, over a few days in late March and early April 2016. Twelve died.

Less than a month later, this mysterious drug – largely unheard of by most Americans – killed the musician Prince and burst on to the national consciousness. Fentanyl, it turned out, was the latest and most disturbing twist in the epidemic of opioid addiction that has crept across the United States over the past two decades, claiming close to 200,000 lives. But Prince, like almost all fentanyl’s victims, probably never even knew he was taking the drug.

“The number of people overdosing is staggering,” said Lieutenant Tracy Morris, commander of special investigations who manages the narcotics task force in Orange County, which has seen a flood of the drug across the Mexican border. “It is truly scary. They don’t even know what they’re taking.”

The epidemic of addiction to prescription opioid painkillers, a largely American crisis, sprung from the power of big pharmaceutical companies to influence medical policy. Two decades ago, a small family-owned drug manufacturer, Purdue Pharma, unleashed the most powerful prescription painkiller yet sold over the pharmacist’s counter. Even though it was several times stronger than anything else on the market, and bore a close relation to heroin, Purdue claimed that OxyContin was not addictive and was safe to treat even relatively minor pain. That turned out not to be true.

It spawned an epidemic that in the US claims more lives than guns, cutting across class, race and geographic lines as it ravages communities from white rural Appalachia and Mormon Utah to black and Latino neighbourhoods of southern California. The prescription of OxyContin and other painkillers with the same active drug, oxycodone, became so widespread that entire families were hooked. Labourers who wrenched a back at work, teenagers with a sports injury, just about anyone who said they were in pain was put on oxycodone. The famous names who ended up as addicts show how indiscriminate the drug’s reach was; everyone from politician John McCain’s wife Cindy to Eminem became addicted.

Clinics staffed by unscrupulous doctors, known as “pill mills”, sprung up churning out prescriptions for cash payments. They made millions of dollars a year. By the time the epidemic finally started to get public and political attention, more than two million Americans were addicted to opioid painkillers. Those who finally managed to shake off the drug often did so only at the cost of jobs, relationships and homes.

After the government finally began to curb painkiller prescriptions, making it more difficult for addicts to find the pills and forcing up black market prices, Mexican drug cartels stepped in to flood the US with the real thing – heroin – in quantities not seen since the 1970s. But, as profitable as the resurgence of heroin is to the cartels, it is labour intensive and time-consuming to grow and harvest poppies. Then there are the risks of smuggling bulky quantities of the drug into the US.

The ingredients for fentanyl, on the other hand, are openly available in China and easily imported ready for manufacture. The drug was originally concocted in Belgium in 1960, developed as an anaesthetic. It is so much more powerful than heroin that only small quantities are needed to reach the same high. That has meant easy profits for the cartels. The Drug Enforcement Administration (DEA) has said that 1kg of heroin earns a return of around $50,000. A kilo of fentanyl brings in $1m.

At first the cartels laced the fentanyl into heroin to increase the potency of low-quality supplies. But prescription opioid painkillers command a premium because they are trusted and have become increasingly difficult to find on the black market. So cartels moved into pressing counterfeit tablets.

But making pills with a drug like fentanyl is a fairly exact science. A few grammes too much can kill. “It’s very lethal in very small doses,” said Morris. “Even as little as 0.25mg can be fatal. One of our labs had a dime next to 0.25mg and you could barely see it. It’s about the size of the head of a pin. Potentially that could kill you.”

The authorities liken buying black market pills to playing Russian roulette. “These pills sold on the street, nobody knows what’s in them and nobody knows how strong they are,” said Barbara Carreno of the DEA.

After Prince died, investigators found pills labelled as prescription hydrocodone, but made of fentanyl, in his home, suggesting he bought them on the black market. The police concluded he died from a fatal mix of the opioid and benzodiazepine pills, a particularly dangerous combination. It is likely Prince did not even know he was taking fentanyl.

Others knowingly take the risk. In his long battle with addiction, Michael Jackson, used a prescription patch releasing fentanyl into his skin among the arsenal of drugs he was fed by compliant doctors. Although it was two non-opioids that killed him, adding fentanyl into the mix was hazardous.

Jerome Butler, a former driver for Budweiser beer who was training to be a security guard, thought he was taking a prescription pill called Norco. His mother’s voice breaks as she recounts what she knows of her son’s last hours. Natasha said she was aware he used cannabis, but had no idea he was hooked on opioid painkillers. She said her son at one time had a legitimate prescription and may have become addicted that way. She has since discovered he was paying a doctor, well known for freely prescribing opioids, to provide pills.

“I didn’t even know,” she said. “You find stuff out after. It’s killing me because they’re saying, ‘Well, yeah, Jerome was taking them pills all the time.’ And I’m like, ‘He was doing what?’”

Jerome may have had a prescription, but like many addicts he will have needed more and more. The pill that killed him was stamped M367, a marking used on Norco pills made of an opioid, hydrocodone. It was a fake with a high dosage of fentanyl.

“If Jerome had known it was fentanyl he would never have took that,” said Natasha. “This ain’t like crack or a recreational drug that people been doing for so many years and survived it but at 60 or 70 die from a drug overdose because their heart can’t take it no more. This is fentanyl. The first time you take it you’re not coming back. You’re gone.”

That wasn’t strictly true of the batch that hit Sacramento. It claimed 11 other lives. The youngest victim was 18-year-old George Berry from El Dorado Hills, a mostly white upscale neighbourhood. The eldest was 59. But others survived. Some were saved by quick reactions; doctors were able to hit them with an antidote before lasting damage was done. Others swallowed only enough fentanyl to leave them seriously ill but short of death.

It was a matter of luck. When investigators sent counterfeit pills seized after the Sacramento poisonings for testing at the University of California, they found a wide disparity in the amount of fentanyl each contained. Some pills had as little as 0.6mg. Others were stuffed with 6.9mg of the drug, which would almost certainly be fatal.

‘The number of people overdosing is staggering’: fentanyl. Illustration: Justin Metz for the Observer

The DEA thinks the difference was probably the result of failing to mix the ingredients properly with other powders, which resulted in the fentanyl being distributed unevenly within a single batch of counterfeit pills.

That probably explains the unpredictable mass overdosing popping up in cities across the US. In August, 174 people overdosed on heroin in six days in Cincinnati, which has one of the fastest-growing economies in the Midwest. Investigators suspect fentanyl because the victims needed several doses of an antidote, Naloxone, where one or two will usually suffice with heroin. The same month, 26 people overdosed on fentanyl-laced heroin in a four-hour period in Huntington, a mostly white city in one of the poorest areas of West Virginia. In September seven people died from fentanyl or heroin overdoses in a single day in Cuyahoga County, Ohio.

The US authorities don’t know for sure how many people fentanyl kills because of the frequency with which it is mixed with heroin, which is then registered as the cause of death. The DEA reported 700 fatalities from fentanyl in 2014 but said it is an underestimate, and rising. In 2012, the agency’s laboratory carried out 644 tests confirming the presence of fentanyl in drug seizures. By 2015, the number of positive tests escalated to 13,002.

The police did not have to look far for the source of the drug that killed Jerome. He and his girlfriend were staying at the house of her aunt, Mildred Dossman, while they waited for their own place to live. Jerome was smoking cannabis and drinking beer with Dossman’s son, William. Shortly before 1am, William went to his mother’s bedroom and came back with the fake Norco pill. Jerome took it and said he was going to bed.

Jerome’s girlfriend was in jail after being arrested for an unpaid traffic fine and so he was alone with their 18 month-old daughter, Success, lying next to him.

“The doctors explained to me that within a matter of minutes he went into cardiac arrest,” said his mother. “Then as he lay there that’s when time progressed for the organs to be poisoned by fentanyl. He was dying with his daughter next to him.” Natasha said other people in the house heard her son in distress, complaining his heart was hurting. But they did nothing because they were afraid that calling an ambulance would also bring the police.

It was not until 10 hours later that the Dossmans finally sought help from a neighbour who knew Jerome. He tried CPR and then called the medics. The police came, too, and in time Mildred Dossman, 50, was charged with distributing fentanyl and black market opioid painkillers. She was the local dealer.

The DEA is tightlipped about the investigation into the Sacramento deaths as its agents work on persuading Dossman to lead them to her suppliers. But it is likely she was getting the pills from Mexican cartels using ingredients from labs in China where production of fentanyl’s ingredients is legal.

Carreno said some Mexican cartels have long relationships with legitimate Chinese firms which for years supplied precursor chemicals to make meth amphetamine.

Packages of fentanyl are often moved between multiple freight handlers so their origins are hard to trace. Larger shipments are smuggled in shipping containers. Last year, six Chinese customs officials fell ill, one of them into a coma, after seizing 72kg of various types of fentanyl from a container destined for Mexico.

American police officers have faced similar dangers. In June, the DEA put out a video warning law enforcement officers across the US that fentanyl was different to anything they have previously encountered and they should refrain from carting seizures back to the office.

“A very small amount ingested, or absorbed through the skin, can kill you,” it said.

A New Jersey detective appears in the video after accidentally inhaling “just a little bit of fentanyl puffed into the air” during an arrest: “It felt like my body was shutting down… I thought that was it. I thought I was dying.”

Along with the Mexican connection, a home-grown manufacturing industry has sprung up in the US. Weeks after Jerome died, agents arrested a married couple pressing fentanyl tablets in their San Francisco flat.

Candelaria Vazquez and Kia Zolfaghari made the drug to look like oxycodone pills. They sold them across the country via the darknet using Bitcoin for payment – on one occasion Zolfaghari cashed in $230,000. The couple shipped the drugs through the local post office. Customers traced by the DEA thought they were buying real painkiller pills.

The couple ran the pill press in their kitchen. According to a DEA warrant, a dealer said Zolfaghari made large numbers of tablets: “He could press 100 out fast as fuck.”

The pair made so much money that agents searching their flat found luxury watches worth $70,000, more than $44,000 in cash and hundreds of “customer order slips” which included names, amounts and tracking numbers. The flat was stuffed with designer goods. The seizure warrant described Vazquez’s shoe collection as “stacked virtually from floor to ceiling”. Some still had the $1,000 price tags on them. Zolfaghari was arrested carrying a 9mm semi-automatic gun and about 500 pills he was preparing to post.

Even as Americans are getting their heads around fentanyl, it is being eclipsed. In September, the DEA issued a warning about the rise of a fentanyl variant that is 100 times more powerful – carfentanil, a drug used to tranquilise elephants.

“Carfentanil is surfacing in more and more communities,” said the DEA’s acting administrator, Chuck Rosenberg. “We see it on the streets, often disguised as heroin. It is crazy dangerous.”

The drug has already been linked to 19 deaths in Michigan. Investigators say that with its use spreading, it is almost certainly claiming other lives. Dealers are also getting it from China, where carfentanil is not a controlled drug and can be sold to anyone.

Natasha Butler is still trying to understand the drug that killed her son. She wants to know why it is that it took Jerome’s death for her to even hear of it. She accuses the authorities of failing to warn people of the danger, and politicians of shirking their responsibilities.

A bill working its way through California’s legislature stiffening sentences for fentanyl dealing died in the face of opposition from the state’s governor, Jerry Brown, because it would put pressure on the already badly crowded prisons.

“I’m so dumbfounded. How does that happen?” says Natasha. Her tears come frequently as she sits at a tiny black table barely big enough to seat three people. She talks about Jerome and the tragedy for his three children, including Success, who she is now raising.

But some of the tears are to mourn the devastating impact on her own life. “Look where I’m at. I was in Louisiana. I had a house. I had a job. I had a car. I had a life. I worked every day. I was a manager for a major company. I came here, I became homeless. I had to move into this apartment to help out my granddaughter,” she said. “You see me. This is what my kitchen table is. My son is dead. He had three kids and those two mothers of those kids are depending on me to be strong. I want answers and help. I say, you got the little fish. Where did they get it from? How did they get it here? You are my government. You are supposed to protect us.”