Overall, the distribution and abuse of illegal drugs pose a serious threat to the safety and security of individuals who live and work in the District of Columbia. The District has a high homicide rate, and many of the killings are drug-related. Approximately 60,000 drug abusers reside in the District (over 10 percent of the population), resulting in higher treatment-related costs per capita than any State in the Nation. Cocaine, particularly crack, is the most serious drug threat to the District. Cocaine abuse is associated with more drug treatment admissions to publicly funded facilities, emergency department mentions, and deaths than is abuse of any other drug. Heroin, primarily South American, poses a growing threat to the District because the number of abusers is high and continues to increase. Long-term heroin abusers who inject the drug continue to purchase low-purity heroin; however, high-purity heroin is purchased by a predominantly younger and more suburban abuser population from Virginia and Maryland. Marijuana is the most readily available, least expensive, and widely abused illicit drug in the District; however, the drug poses a lower threat than cocaine or heroin because the District had no deaths in 1999 related to marijuana abuse, and abuse is not often associated with violent crime. Methamphetamine is increasingly available and abused, but it is not yet a serious problem in the District. Other dangerous drugs are an increasing threat to the District; these include the club drugs MDMA, GHB, and ketamine; the hallucinogens LSD and PCP; the stimulant khat; and diverted pharmaceuticals. 9 tables and 25 references