A total of 60,000 heroin addicts in Baltimore: It's a number that has cropped up in news stories and public pronouncements in various forms over the years.
But it's a statistic with murky origins and that some say is vastly inflated.
Sen. Barbara A. Milkuski included the figure in a recent news release, using information from federal law enforcement, according to her office. A spokesman for the Baltimore office of the Drug Enforcement Administration said it's a tally agents there also recognize.
But it's not a number city health officials believe. They have settled on a much lower figure for the number of Baltimore heroin users, an estimated 11,000.
Counting drug users is difficult, so experts rely on surveys and extrapolations based on what hard data they can find.
Rachel Indek, a spokeswoman for the nonprofit Behavioral Health System Baltimore, said the city's current figure is a midrange number based on federal survey data. The upper bound is 17,000 and the lower estimate 7,000, according to Indek.
The 60,000 figure has been around for years. In 2005, The Baltimore Sun dug into the figure's history and found it likely emerged from a blend of best guesses and misunderstandings.
Addiction researchers traced the 60,000 number to a 1986 study that relied on estimates about the relationship between the rate of people seeking treatment and those addicted but not treated.
The study found about 60,000 people in Baltimore to be "dysfunctional" because of drug use — but only half of them were thought to be heroin users.
Researchers in 1998 also put out a similar total as the highest among a range of estimates, but that included alcohol abusers as well as illicit drug takers. Those researchers thought about 20,000 people in Baltimore were addicted to illegal drugs.
Over time, though, the numbers have shed their context and any hedging and taken on a life of their own.
Now, as overdose deaths rise in Baltimore, the 60,000 figure has taken the stage once more, a symbol of the city's battle with heroin. But it's one that might not be right.