PNGAA Library

Cannabis in Papua New Guinea: David McDonald


This review covers published information on psychoactive drugs, particularly cannabis, in Papua New Guinea. Legal drugs are mentioned to place the illegal drugs into a broader public health context. Although a number of psychoactive drugs were used traditionally (and are used now), cannabis is the only illicit drug for which prevalence of use is currently not negligible. Very little epidemiology research on cannabis use and its individual and public health sequelae has been conducted, although a fuller criminology literature on the topic exists. The published cannabis use prevalence studies are limited in scope, and the most-cited one is of questionable accuracy. The complex interactions between the health of individuals and their social environments are highlighted by the destructive impacts that cannabis cultivation, trafficking and use are having in contemporary PNG.

Papua New Guinea – the nation

Papua New Guinea is the largest nation in the South Pacific. It was colonised by Germany, Britain and Australia from the nineteenth century to Independence in 1975, and was occupied by Japanese and Allied forces during the Second World War. The year 2000 population was estimated to be 5.2 million, with 40 per cent under 15 years of age. Life expectancy at birth is just 53 years. On the 2004 Human Development Index, PNG ranks 133 among the 177 nations listed.1

Traditional psychoactive substances and their use

As in most societies of the world, the use of substances that change the way people think or feel (psychoactive substances, generally referred to as drugs) is an integral part of life. A wide range of traditional psychoactive substances has been used, and are still used, in Papua New Guinea. Perhaps the best known is betel nut (the fruit of Areca catechu) a mild stimulant which is chewed in combination with the leaf or fruit of a pepper plant (Piper betle) and lime powder. (Betel nut chewing is an important cause of oral cancers).2

Tobacco: Nicotiana tabacum is a more recent introduction, but was used prior to the colonial period in many, perhaps most, parts of PNG. The adverse health consequences of tobacco consumption in Oceania, as elsewhere, are well known to health professionals.3

Kava: Piper methysticum was also used and still is used in some localities. It is thought that the plant was introduced from Vanuatu in pre-colonial times. Traditionally, the Admiralty Islands in Manus Province was the area of greatest consumption, although it was also used elsewhere including the coastal areas of the Madang, Morobe and Western Provinces.4 The drug is still used in isolated pockets of the nation, including the Rai Coast of Madang Province and the Fly River delta in Western Province.

Alcohol was also made and consumed in earlier days. According to Papua New Guinean scholar Chamilou Posanau5, who cites various sources:

Traditionally … people in certain areas had their own form of brew. The Tolais (an ethnic group in PNG [who come from the Gazelle Peninsula of East New Britain]) called it "tava" or "yawa" … and the Kiwais (another ethnic group in PNG [who come from the Fly River area]) called it "tubas". These traditional drinks were prepared from young coconut sap (tubas) and other vegetable matter (tava or yawa).

This information is inconsistent with the position adopted by other scholars, that alcohol was not used traditionally in PNG,6 7 8 but it is more likely to be a correct statement of the position.

Posanau also refers to other psychoactive substances, "such as mushrooms, wild ginger, the bark of several species of trees, wild fungi, taro leaves"5 as having been used prior to European contact, without adverse impacts. Further details are provided by Marshall,9 Iamo & Ketan10 and Thomas.11

Colonial era illicit drugs

Very little has been published about the history of cannabis (marijuana) in PNG. Although it is not known when the drug was introduced to that nation, it should be noted that cannabis use was rare in Australia (the colonial power) before the 1960s but its use became widespread among young Australians from the mid-1960s onwards. (Chen, Johnson and Taufa6 are wrong in stating that "cannabis was introduced into Papua New Guinea … in the 1970s‟ (p. 99). I know from personal experiences in PNG "that the drug was available there before that decade.) The late 1960s and early 1970s was the time of greatest involvement of Australians in PNG. By the late 1960s the smoking of cannabis was common among young expatriates in PNG and it was relatively easy to import illegal goods such as cannabis across the customs barrier. The drug was also grown locally by some expatriate smokers for their own use and to share with their friends. Marshall refers to media reports in 1977, 1980 and 1981 of non-nationals being prosecuted for cultivating cannabis.9

Cannabis use has been observed in the Western Pacific only since the Second World War.9 Iamo concluded that "the evidence available to date suggests that cannabis only reached upper Simbu Province [where it is common today] in the mid-to-late 1970s. … While this means that the plant probably was grown elsewhere in Papua New Guinea at an earlier date, it is unlikely that its has an antiquity of more than 50 years in the country".12

Some time between the early 1970s, when the expatriate population of PNG was at its peak, and the mid-1980s when cannabis was recognised as being grown and used by many Papua New Guineans, a process of diffusion from the expatriate to the Papua New Guinean population took place. Some suggest that this was linked to the development of mining, especially the opening of the Ok Tedi mine in Western Province. The rapid uptake of cannabis cultivation, use and trafficking once it was introduced into Papua New Guinean societies is notable, and should be borne in mind as we contemplate the possible introduction of other drugs readily available in the Pacific Islands region, such as the amphetamine-type stimulants, especially methamphetamine.

Contemporary illegal drugs and drug use

This discussion focuses on cannabis, as it is the only illegal drug the use of which is at all prevalent in PNG.

Prevalence of cannabis use and cultivation

The International Narcotics Control Board (INCB) has stated that "… the prevalence of cannabis abuse in Australia and Papua New Guinea is among the highest in the world".13 While this is true for Australia14 it is a remarkable and unjustifiable comment to make with regard to Papua New Guinea. The reason is that no national data exist on the prevalence of cannabis use in PNG. Furthermore, no data exist from which one can extrapolate to make a reasonably accurate estimate of prevalence. One cannot legitimately compare data derived from a national household probability sample survey in Australia with information derived from quite different sources (not surveys) in PNG.

No studies of the prevalence of cannabis use have been reported covering the rural areas of the nation. Two studies have been reported, however, in particular populations in urban areas, as follows.

In the first, Johnson studied the use of and attitudes towards alcohol and other drugs among 50 young adults living in Port Moresby: 25 University of Papua New Guinea students and 25 clerks employed by the PNG Posts and Telecommunications Corporation.15 The published paper does not explain how they were selected for interview. Although apparently not matched samples, the age and sex distributions of the two groups were similar, with ages ranging from 20 to 35 years and the sex distribution being 29 males and 21 females. They came from most of the provinces of PNG. The results of the study included the following:

  • Only seven of the 50 people interviewed responded to the question about their own use of cannabis and of them, three students and one clerk reported having used the drug at some stage in their lives.
  • A question on exposure to use resulted in a somewhat higher level of responses with 36 of the 50 responding. Asked "During the last six months, how often have you been around people who were taking [cannabis]", 28 responded "not at all" and 8 responded "once or twice".
  • All but one of the respondents answered the question "How difficult do you think it would be for you to get [cannabis] if you wanted some?". Of the 49 responses, 13 said "fairly easy", 12 said "very difficult", 11 said "probably impossible", 9 said "fairly difficult" and 4 said "very easy".

From this study published in 1990 one may conclude that, at that time, both the use of cannabis and the availability of the drug were low among young adult university students and clerks living in Port Moresby.

The second prevalence study, also undertaken by Johnson and published in 1998,16 compared the use of alcohol and other drugs among the students of two Port Moresby campuses of the University of Papua New Guinea, namely the main Waigani campus and that at Taurama when the Medical School is located. The survey was self-administered; 45 were completed from each campus, a total of 90 respondents, and the students were selected randomly. (The method of randomisation is not described in the paper.) Fifty-eight of the respondents were male and 32 female. The modal age group was 21-25 years, with 60 of the 90 students falling into this age group and a further 18 in the age range 26-30 years.

  • An important finding was as following: Asked "Do you use marijuana?", three students from each campus (6 of the total) replied "yes". (The number replying "no", and the level of non-response, are not reported.) This represents a user prevalence of 7%E1.
  • The reported data on amount used are unclear. Unfortunately other questions of interest did not differentiate between cannabis and alcohol, betel nut and other drugs.

The conclusion to be drawn from these two studies is that, among the people questioned, the level of cannabis use was low as was its availability to Port Moresby young adults in the 1990s. (This conclusion is in conflict with the perceptions of many informed observers who report the ready availability of cannabis in Port Moresby in the late 1990s, and its widespread use particularly among poor, unemployed youths there as well as in many other parts of the nation.18 Apparently no other prevalence studies of cannabis use have been conducted in PNG.

A third study warrants attention in this context: Iamo's "Spak Brus" in Papua New Guinea.12 "Spak brus" is a Melanesian Pidgin term for cannabis, spak meaning intoxicating and brus meaning home grown tobacco. The importance of this study is not so much what it says but how its findings have been misused. It was a preliminary study of cannabis in four Highlands provinces (the Southern, Western and Eastern Highlands and Simbu), and two north coast provinces (Madang and Morobe), although data are presented in the report on only four provinces, Western Highlands, Simbu, Eastern Highlands and Madang. It is unclear, from the report, if the field work for the study was confined to the provincial headquarters towns or extended into the rural areas. University of PNG students were trained in field research techniques and sent, apparently during the 1990/1991 university Christmas break, to their home provinces in groups of four to six. There they interviewed "drug users, cultivators and dealers", and engaged in participant observation activities. The report on the study presents, for each of the four provinces, national census data, local names for cannabis, locality of cultivation, comments on growers, dealers and consumers, prices and incomes, marketing strategies, criminal justice system involvement and socio-economic impact. Unfortunately overall conclusions in most of these areas are not presented in the published report. It includes a valuable discussion of the purported link between cannabis use and violence (concluding that cannabis use does not cause violence), as well as drugs policy and legislation.

It is crucial to note that it was not a prevalence survey; it was a study of drug users, cultivators and dealers. It produced no data that enables conclusion to be drawn about the extent of cannabis cultivation and use in the provinces studied.

A typical illustration of how the study results have been misinterpreted and, indeed, misused, is an article19 in the September 1998 issue of the Papua New Guinea Magazine, an insert of the Post-Courier newspaper, the largest circulation newspaper in the nation. Under the headline "K56m earned by four provinces from marijuana", the author states that the survey showed that, in the four provinces:

… there were 123,000 households involved in cultivating marijuana out of 170,467 households surveyed. The monetary value derived from marijuana cultivation in those four provinces surveyed was K56.8 million. Each province was earning K15.6m. Today it must be many times more (p. 9).

In reality, the journalist can perhaps be forgiven for publishing these unjustifiable estimates as the logic of Iamo's 1991 paper is flawed. Iamo's figures seem to be based on the assumption that all, or almost all, food and coffee growers in the Highlands provinces, and all growers of food crops in the Madang Province, grow cannabis. The numbers produced under these assumptions are then multiplied by an estimated value of cannabis sales by cultivators to produce an estimate of the value of cannabis sales by growers. Neither data nor argument is presented in the paper to support the conclusion that all or virtually all farmers grow cannabis, an observation not supported by any other source. Iamo's 1991 paper is useful for its discussion of the cannabis/violence link and for some of its description of cannabis markets in the provinces reported upon, but cannot be relied upon as a source of information about the number of cannabis growers nor the value of their production. To use it for this purpose is to promulgate grossly inflated estimates.E2

Research among cannabis users

A study of current and former cannabis users was conducted in 1998 as part of a rapid situation assessment of illicit drug use and related problems in PNG.18 Although the report on that study has not been widely distributed, copies are available from the author and a summary is in press.21

Clinical observations: cannabis (and other drugs) and mental illness

Two studies have been published reporting clinical observations of psychoactive substance use by psychiatric patients in PNG in which cannabis is mentioned. In the first, Johnson presented data on a prospective study of patients admitted to the Port Moresby General Hospital for health problems directly associated with drug use.22 The drugs involved were alcohol, cannabis and diazepam. The patients were aged from 15 to 35 years; all were Papua New Guineans; they included 28 males and 2 females. Important findings for this review include the following:

  • Cannabis was involved in 20 of the 30 patients; 12 were diagnosed as suffering from "schizophrenia and cannabis induced psychosis/cannabis abuse"; 6 were diagnosed as "cannabis induced psychosis"; and 2 were suffering from multiple illnesses including psychosis and cannabis "abuse";
  • Five were given a diagnosis of diazepam dependence and the remaining five patients had alcohol-related health problems.

The second study reporting clinical observations was conducted by Pal.23 His study covered all 64 mental patients referred to the Laloki Psychiatric Hospital near Port Moresby by the courts for assessment and treatment. As the author points out, "as this psychiatric hospital is the only referral psychiatric hospital, so the patient population could be assumed to represent the forensic psychiatric population of the country" (p. 89). The ages ranged from 10 to 59 years; 60 were male and 4 female. Thirty of the 64 had been admitted to hospital for mental illness prior to committing the offence for which they were in custody. Significant findings were that:

  • 27 of the 64 patients were diagnosed with schizophrenia; 8 with psychosis not otherwise classified; 4 with personality disorder; and the remainder with a variety of diagnoses. None was specifically drug-related, e.g. the drug dependence syndrome.
  • One-third of the total (21 patients) were reported to have a history of drug abuse: "10 (15.6%) were alcoholics, six (9.4%) abused cannabis and five (7.8%) abused both alcohol and cannabis … No one was found to have narcotic abuse…" (p. 94).

Unfortunately, the term "drug abuse" is not defined in the paper so it is not possible to tell if the six former cannabis using patients were experiencing any cannabis related harm. We also cannot tell from the study if cannabis use was involved in the offence or offences for which the patients were in custody.

Drug availability and law enforcement

Additional insights come from criminological research in PNG. In the late 1980s Harris discussed drugs in the context of his ethnographic research into criminal (raskal) gangs in Port Moresby.24 He noted that, at that time, most cannabis use was among expatriates but some Papua New Guineans were also using this drug.

Gang involvement in the drugs trade was well established by the late 1980s, according to Harris. By then, PNG had become a cannabis producing nation, with the drug marketed both internally and on the international market, primarily to Australia. He stated that "gangs are taking a major cut of this market and are increasingly displacing the expatriate middlemen who until now have dominated the market".25

Dinnen reviewed the situation in PNG in 1994.26 He pointed out that "a comparatively small number of committed, 'hard-core' criminals are supplemented by a large number of peripheral youth who drift in and out of crime" (p. 401). Stating that cannabis was grown principally in the Highlands and that it had proved impossible for the authorities to contain its cultivation, he argued that, "for growers with few other opportunities for generating cash, marijuana provides a ready option for acquiring the funds to pay school fees and other requirements" (p. 403). He concluded that significantly less was said and done about alcohol-related problems than those linked to cannabis, despite the fact that alcohol-related problems were (and are) "the most serious and injurious form of substance abuse in PNG" (p. 403). Dinnen's central theme was that most of the serious issues labelled as "law and order problems", including cannabis cultivation, supply and use, and violence, "… represent alternative avenues to accessing resources. The appeal of these options can only increase as the [economic] crisis deepens, and the resource-starved criminal justice system is in no position to offer other than token resistance" (p. 407).

This theme of involvement in the cannabis industry for economic reasons was illustrated by journalist/researcher Ben Bohane.27 Writing in 1995 about cannabis in the Simbu Province, he reports that a gang member advised him that cannabis was the main source of income for the gangs in the rural areas of that province. A gang leader is quoted as saying:

Growing spak brus to us is not a crime. It's business. When we smoke it, it gives us good ideas to make guns and road blocks and hold up vehicles. We are able to sell it to white men for money, and to others in exchange for guns…

Australia introduced the cash economy to us, but how can we make a living? We can't even get a good education so how can we get jobs? (p. 17)


This review has considered the literature on cannabis in PNG in the colonial period and since Independence. The limited literature on the epidemiology of cannabis use and related harms has been reviewed and insights from the criminological literature have been presented. The complex interactions between the health of individuals and their social environments are highlighted by the impact that cannabis cultivation and supply is having today in PNG, especially in the Highlands provinces. There cannabis production, trafficking and use; firearm manufacture, trafficking and use; and disputes between groups over access to resources (both traditional and modern) are interwoven, creating immense social problems for the people, problems apparently far beyond the capacity of the authorities and traditional social control methods to cope with.28

It seems that social and economic development will continue to be retarded in much of PNG as a result of what appears to be a still-increasing impact of cannabis, along with the continuing severe impacts of interpersonal violence linked to the consumption of alcoholic beverages. The International Narcotics Control Board, who sent a investigative mission to PNG in 2003, concluded that the PNG Government is ill-equipped to deal with the current and potential problems associated with illegal drugs in that nation.29


1. United Nations Development Program. Human development report 2004: cultural liberty in today's diverse world. New York: United Nations Development Program; 2004.
2. Norton SA. Betel: consumption and consequences. J Am Acad Dermatol 1998;38(1):81-8.
3. Marshall M. The second fatal impact: cigarette smoking, chronic disease, and the epidemiological transition in Oceania. Soc Sci Med 1991;33(12):1327-42.
4. Lebot V, Merlin M, Lindstrom L. Kava - the Pacific drug. New Haven: Yale University Press; 1992.
5. Posanau CS. Substance abuse in the Pacific Islands, with special reference to Papua New Guinea. Int J Ment Health 1997;26(3):55-68.
6. Chen PCY, Johnson FYA, Taufa T. Societal and health aspects of psychoactive drug abuse in Papua New Guinea. Pac Health Dialog 1999;6(1):93-100.
7. Marshall M. Alcohol consumption as a public health problem in Papua New Guinea. Int J Addict 1988;23(6):573-89.
8. Loeb EM. Primitive intoxicants. Q J Stud Alcohol 1943;4(3):387-98.
9. Marshall M. An overview of drugs in Oceania. In: Lindstrom L, editor. Drugs in Western Pacific societies: relations of substance. Lanham MD: University Press of America; 1987.
10. Iamo W, Ketan J. How far under the influence? Alcohol-related law and order problems in the Highlands of Papua New Guinea. Port Moresby: National Research Institute; 1992.
11. Thomas B. The psychoactive flora of Papua New Guinea. J Psychoactive Drugs 2003;35(2):285-93.
12. Iamo W. "Spak brus" in Papua New Guinea. Port Moresby: National Research Institute; 1991.
13. International Narcotics Control Board. Report of the International Narcotics Control Board for 1997. New York: United Nations; 1998.
14. Hall W, Pacula R. Cannabis use and dependence: public health and public policy. Port Melbourne, Vic.: Cambridge; 2003.
15. Johnson FA. An epidemiological survey of alcohol and drug abuse in the National Capital District of Papua New Guinea. Med Law 1990;9(2):797-830.
16. Johnson FA. A study of substance abuse on two campuses of University of Papua New Guinea. Med Law 1998;17:229-41.
17. McGeorge JM. The effect of decriminalisation of cannabis on patterns of use among university students [Honours thesis]. University of Melbourne; 1994.
18. Papua New Guinea National Narcotics Bureau. Rapid situation assessment of drug abuse in Papua New Guinea, 1998; a report prepared by David McDonald and Michael Anis Winmarang. Port Moresby: Papua New Guinea National Narcotics Bureau; 1999.
19. Matbob P. Drugs will be an epidemic by the year 2000. Post-Courier, Papua New Guinea Magazine 1998 September 1998:7-9.
20. Ivarature H. Drugs, arms and national security: the global becomes local in Papua New Guinea. Port Moresby: National Research Institute; 1997.
21. McDonald D. A rapid situation assessment of drug abuse in Papua New Guinea. Drug and Alcohol Review in press.
22. Johnson FA. Clinical observations on substance abuse related health problems at the Port Moresby General Hospital, National Capital District, Papua New Guinea. Med Law 1994;13(3-4):251-62.
23. Pal S. Mental disorders in abnormal offenders in Papua New Guinea. Med Law 1997;16(1):87-95.
24. Harris BM. The rise of rascalism: action and reaction in the evolution of rascal gangs. Port Moresby: Institute of Applied Social and Economic Research; 1988. (IASER Discussion Paper).
25. Harris BM. The rascal gangs of Port Moresby. Criminology Australia 1989;1(3):3-4.
26. Dinnen S. Papua New Guinea in 1994: the most turbulent year? Current Issues in Criminal Justice 1995;6(3):395-408.
27. Bohane B. The new bushrangers. The Bulletin 1995;116(5976):14-9.
28. Ware M. Savage harvest. Time 2001 9 April;14):24-31.
29. International Narcotics Control Board. Report of the International Narcotics Control Board for 2003. New York: United Nations; 2004.
E1 This figure is similar to that observed among undergraduate students at the Australian National University, Canberra, in 1994.17
E2 A similar conclusion was reached by one of Iamo's colleagues.20 In contrast, Chen, Johnson and Taufa uncritically accepted and reproduced Iamo's findings which are simply not supported by the data presented in his report.6