North American narcotics authorities were alarmed by the seizure in September in suburban Toronto of nearly 100 pounds of carfentanil, the synthetic opioid developed as a large-animal tranquilizer, reports The Guardian. It is believed to be the largest volume of the opioid–described by the DEA as “crazy dangerous”–ever seized in North America. The drug burst into public view last year after officials began to warn that it was being cut with heroin and other illicit drugs, leaving a rash of overdoses and deaths in its wake. It is regarded as vastly more toxic than either fentanyl or morphine. “An amount as small as a grain of sand can kill you,” said one Canadian medical expert.
Authorities in Cincinnati said the drug was one possible explanation for why 174 people in the US city had overdosed in the span of six days. Dealers were cutting carfentanil into heroin and other drugs to offer users a hard-hitting, longer-lasting high, officials said as they scrambled to shore up supplies of the antidote. While it often takes just one or two shots of naloxone to counteract a heroin overdose, overdoses involving carfentanil can take half a dozen shots or more. The use of carfentanil by dealers is complicated by a lack of information regarding potency, said Hakique Virani, a Canadian doctor who specializes in addiction medicine. He said drug dealers may be embracing carfentanil because it is easy to conceal. “It’s quite necessary in a prohibition environment for drug traffickers to move towards more toxic, smaller chemicals because they’re much easier to traffic,” said Virani.