The hydrochloride salt is soluble in three parts of water, whereas a gram of morphine hydrochloride dissolves in 16 ml of water; for all common purposes, the pure powder for hospital use can be used to produce solutions of virtually arbitrary concentration. When the powder appeared on the street, this very small volume of powder needed for a dose means that overdoses are likely for those who mistake it for heroin or other powdered narcotics, especially those that have been diluted prior to consumption. Endogenous production
Hydromorphone is made from morphine via catalytic hydrogenation and also is produced in trace amounts by human and other mammalian metabolisms of morphine. It occasionally appears in assays of opium latex in very small quantities, apparently forming in the plant in an unknown percentage of cases under poorly understood conditions. Bacteria
Some bacteria have been shown to be able to turn morphine into closely related drugs, including hydromorphone and dihydromorphine among others. The bacterium Pseudomonas putida serotype M10 produces a naturally-occurring NADH-dependent morphinone reductase that can work on unsaturated 7,8 bonds, with result that, when these bacteria are living in an aqueous solution containing morphine, significant amounts of hydromorphone form, as it is an intermediary metabolite in this process; the same goes for codeine being turned into hydrocodone.The process gave rise to various concentrations of hydromorphone, dihydromorphine, hydromorphinol, and oxymorphone during the experiments.
Article discussing withdrawal of extended-release hydromorphone from the U.S. market
Dihydromorphinones from morphine & analogues
United States DEAs perspective, including statistics on manufacture and prescription levels from 1998 to 2006
"When is a pain doctor a drug pusher? ", The New York Times, 17 Jun 2007