title: 'What if you live on top of a bakery and you like cakes?'-Drug use and harm trajectories before, during and after the emergence of Silk Road.
abstract: Cryptomarkets are digital platforms that use anonymising software (e.g. Tor) and cryptocurrencies (e.g. Bitcoin) to facilitate peer-to-peer (P2P) trade of goods and services. Their emergence has facilitated access to a wide range of high-quality psychoactive substances, according to surveys of users. In this paper, we ask the question 'How does changing access to drugs through cryptomarkets affect the drug use and harm trajectories of their users?'
  
  
  
  We conducted a digital ethnography spanning 2012-2014, a period that included the seizure of the original Silk Road marketplace and forum by law enforcement. Using encrypted online chat, we interviewed 17 people who reported using Silk Road to purchase illicit drugs. The interviews were in-depth and unstructured, and also involved the use of life history timelines to trace trajectories. Transcripts were analysed thematically using NVivo.
  
  
  
  For some, Silk Road facilitated initiation into drug use or a return to drug use after cessation. Typically, participants reported experiencing a glut of drug consumption in their first months using Silk Road, described by one participant as akin to 'kids in a candy store'. There was evidence that very high availability reduced the need for drug hoarding which helped some respondents to moderate use and feel more in control of purchases made online. Cryptomarket access also appeared to affect solitary and social drug users differently. Most participants described using other cryptomarkets after the closure of Silk Road, albeit with less confidence.
  
  
  
  In the context of high levels of drug access, supply and diversity occurring within a community regulated environment online, the impacts of cryptomarkets upon drug use trajectories are complex, often posing new challenges for self-control, yet not always leading to harmful outcomes. A major policy challenge is how to provide support for harm reduction in these highly volatile settings.
authors.affiliation: Drug Policy Modelling Program, National Drug and Alcohol Research Centre, UNSW Australia, Sydney, NSW 2052, Australia; National Drug Research Institute, Faculty of Health Sciences, Curtin University, GPO Box U1987, Perth, WA 6845, Australia; Centre of Population Health, Burnet Institute, 85 Commercial Road, Melbourne, Victoria 3004, Australia. Electronic address: m.barratt@unsw.edu.au.
authors.forename: Monica J
authors.initials: MJ
authors.lastname: Barratt
authors.affiliation: National Drug Research Institute, Faculty of Health Sciences, Curtin University, GPO Box U1987, Perth, WA 6845, Australia.
authors.forename: Simon
authors.initials: S
authors.lastname: Lenton
authors.affiliation: National Drug Research Institute, Faculty of Health Sciences, Curtin University, GPO Box U1987, Perth, WA 6845, Australia.
authors.forename: Alexia
authors.initials: A
authors.lastname: Maddox
authors.affiliation: School of Communication and Creative Arts, Deakin University, 1 Gheringhap Road, Geelong, Victoria, Australia.
authors.forename: Matthew
authors.initials: M
authors.lastname: Allen
mesh_terms: D000293:Adolescent; D000328:Adult; D003132:Commerce / Q000191:economics; D064423:Drug Trafficking / Q000191:economics*; D055030:Drug Users / Q000523:psychology*; D005260:Female; D040261:Harm Reduction; D006801:Humans; D013287:Illicit Drugs / Q000191:economics / Q000600:supply & distribution*; D020407:Internet; D007407:Interviews as Topic; D008297:Male; D012984:Software; D019966:Substance-Related Disorders / Q000453:epidemiology*; D055815:Young Adult
chemical_list: D013287:Illicit Drugs
keywords: Availability; Cryptomarkets; Digital ethnography; Drug markets; Drug trajectories; Silk Road