The death of acclaimed actor Philip Seymour Hoffman, who was reportedly discovered in his West Village apartment surrounded by heroin packets with a needle in his arm, serves as a tragic reminder of the drug's inherent dangers, as well as its continuing popularity. CNN reports that a government drug survey found that in 2002, 166,000 Americans said they had used heroin. In 2012, that number more than doubled, to 355,000. Making matters worse, there's currently some deadly tainted heroin in circulation.

Heroin tainted with fentanyl has been killing addicts throughout the Northeast since at least last fall. Fentanyl-tainted heroin has been blamed for at least 37 fatal overdoses in Maryland since September, and last month 22 people in western Pennsylvania died after injecting fentanyl-laced heroin. "Heroin is pummeling the northeast, leaving addiction, overdoses and fear in its wake," James Hunt of the DEA's New York Office said in a statement. From a troubling article in the Atlantic:

Fentanyl tainted bags go fast; ironically, when news of a batch laying users low spreads on the streets heavy users seek the potent bags out by their brand stamp. Overdoses become advertisements for strong product. So as quick as the alarm goes up the supply runs dry, only to pop up in the black market somewhere else.

Tainted drugs batches are hard to track, hard to predict and useful advice that keeps users "safe"—in a relative sense—like not running the whole barrel at once (but injecting a little to see how potent the bag is) can be unrealistic for street addicts trying to quickly get a shot off before getting nabbed by the cops.

The NYC Medical Examiner has not completed a toxicology report, so the cause of Hoffman's death remains a matter of speculation. But last year Hoffman relapsed after being clean for 23 years and entered a rehab program. In 2006, he told 60 Minutes, "It was all that [drugs and alcohol], yeah. It was anything I could get my hands on...I liked it all. I went [to rehab], I got sober when I was 22 years old.You get panicked.and I got panicked for my life."