title: Issues in the implementation and evolution of the commercial recreational cannabis market in Colorado.
abstract: BACKGROUND
  For almost a century, the cultivation, sale and use of recreational cannabis has been prohibited by law in most countries. Recently, however, under ballot initiatives four states in the US have legalised commercial, non-medical (recreational) cannabis markets. Several other states will initiate similar ballot measures attached to the 2016 election that will also appoint a new President. As the first state to implement the legislation in 2014, Colorado is an important example to begin investigating early consequences of specific policy choices while other jurisdictions consider their own legislation although the empirical evidence base is only beginning to accrue.
  
  
  METHODS
  This paper brings together material sourced from peer reviewed academic papers, grey literature publications, reports in mass media and niche media outlets, and government publications to outline the regulatory model and process in Colorado and to describe some of the issues that have emerged in the first 20 months of its operation.
  
  
  RESULTS
  These issues include tension between public health and profit, industry and investment, new methods of consumption, the black market and product testing.
  
  
  CONCLUSIONS
  The paper concludes that, while it is too early to determine the impact of the scheme, and noting that it includes some features designed to mitigate adverse impacts, it faces major challenges. Not least of these are the lack of an effective overarching federal regulatory structure, as a consequence of the federal prohibition on cannabis, combined with a rapidly growing cannabis industry which, like other industries, will seek to exploit loopholes to maximise profit.
authors.affiliation: National Drug Research Institute, Faculty of Health Sciences, Curtin University, Perth, WA, Australia. Electronic address: todd.subritzky@postgrad.curtin.edu.au.
authors.forename: Todd
authors.initials: T
authors.lastname: Subritzky
authors.affiliation: School of Psychology and Speech Pathology, Curtin University, Kent St, Bentley, WA, 6102, Australia.
authors.forename: Simone
authors.initials: S
authors.lastname: Pettigrew
authors.affiliation: National Drug Research Institute, Faculty of Health Sciences, Curtin University, Perth, WA, Australia.
authors.forename: Simon
authors.initials: S
authors.lastname: Lenton
keywords: Cannabis; Colorado; Dabbing; Edibles; Marijuana; Regulation; Testing