US federal cocaine essential ('precursor') chemical regulation impacts on US cocaine availability: an intervention time-series analysis with temporal replication

Background and AimsResearch shows that essential/precursor chemical controls have had substantial impacts on US methamphetamine and heroin availability. This study examines whether US federal essential chemical regulations have impacted US cocaine seizure amount, price and purityindicators of cocaine availability. DesignAutoregressive integrated moving average (ARIMA)-intervention time-series analysis was used to assess the impacts of four US regulations targeting cocaine manufacturing chemicals: potassium permanganate/selected solvents, implemented October 1989 sulfuric acid/hydrochloric acid, implemented October 1992; methyl isobutyl ketone, implemented May 1995; and sodium permanganate, implemented December 2006. Of these chemicals, potassium permanganate and sodium permanganate are the most critical to cocaine production. SettingConterminous United States (January 1987April 2011). MeasurementsMonthly time-series: purity-adjusted cocaine seizure amount (in gross weight seizures < 6000 grams), purity-adjusted price (all available seizures), and purity (all available seizures). Data source: System to Retrieve Information from Drug Evidence. FindingsThe 1989 potassium permanganate/solvents regulation was associated with a seizure amount decrease (change in series level) of 28% (P < 0.05), a 36% increase in price (P < 0.05) and a 4% decrease in purity (P < 0.05). Availability recovered in 1-2 years. The 2006 potassium permanganate regulation was associated with a 22% seizure amount decrease (P < 0.05), 100% price increase (P < 0.05) and 35% purity decrease (P < 0.05). Following the 2006 regulation, essentially no recovery occurred to April 2011. The other two chemical regulations were associated with statistically significant but lesser declines in indicated availability. ConclusionsIn the United States, essential chemical controls from 1989 to 2006 were associated with pronounced downturns in cocaine availability.