Cannabis use trends in South Africa

Cannabis is not indigenous to southern Africa, having probably been introduced into the Mozambique area in pre-colonial times by Arab traders many centuries ago. It was adopted by the Khoikhoi as a valued intoxicant and herbal remedy that was chewed or boiled, and was traded from the Xhosa communities living in the eastern parts of South Africa. The smoking of it began after the introduction of the smoking pipe by the European colonialists. It was not until 1928 that cannabis became illegal.


Cannabis use trends in South Africa
Cannabis is not indigenous to southern Africa, having probably been introduced into the Mozambique area in pre-colonial times by Arab traders many centuries ago. It was adopted by the Khoikhoi as a valued intoxicant and herbal remedy that was chewed or boiled, and was traded from the Xhosa communities living in the eastern parts of South Africa. The smoking of it began after the introduction of the smoking pipe by the European colonialists. It was not until 1928 that cannabis became illegal. 1 Historically, the controlled use and consumption of cannabis was ubiquitous throughout southern Africa. Strict rules and values governed the circumstances under which it could be used.
Availability was usually controlled by tribal elders. However, in the context of a modernising, increasingly urbanised society, where traditional controls are breaking down, the use of cannabis has now become the domain of the younger user and the polyuser. 2,3 South Africa is a large producer of cannabis (the world's third largest), most of which is consumed in the southern African region, but at least some of which finds its way to Europe. 4 Cannabis is cultivated in South Africa, and also imported from neighbouring countries (Swaziland, Lesotho, Mozambique, Zimbabwe), exported to some of the neighbouring countries (e.g. Namibia) and Europe (mainly Holland, UK) and, of course, consumed in South Africa. Cultivation of illicit drugs appears confined to the widespread cultivation of cannabis (but not opium or coca) in the eastern half of South Africa and in some northern areas.

Human Sciences Research Council, Pretoria
The purpose of this review is to synthesise cannabis use data from surveys, specialised alcohol and drug treatment centres, cannabis-related trauma unit admissions and arrestee studies over the past 12 years in South Africa.
Results indicate that cannabis is the most common illicit substance used in South Africa, with particularly high use among the youth. Current self-reported cannabis use was 5 -10% among adolescents and 2% among adults, higher among men than women, higher in urban than rural areas, higher in the urban provinces of Western Cape and Gauteng than the other provinces and higher among coloureds and whites than other racial groups. Cannabis is commonly misused by trauma patients (29 -59%) and is often associated with crime (39%). There has been an increase in seizures and treatment demand for cannabis. The current (2006) treatment demand for the whole country was 17% for cannabis and 3.4% for cannabis and mandrax (methaqualone), which has implications for treatment service delivery. Screening and brief intervention of substance (cannabis) use should be included in health care settings.
nightclubs. The street vendor may be an employee of the retailer, working for packets of dagga that he can then re-sell. 7 Cannabis is the most common primary drug for which adolescents seek treatment, but treatment data provide a poor picture of its use in the general population. Cannabis is the illicit drug most likely to be consumed by high-school students and is commonly used by young rave club attendees. Although many young people do not perceive cannabis to be a drug that gives rise to problems, the South African Community Epidemiology Network on Drug Use (SACENDU) adolescent treatment demand, trauma, and arrestee data reflect the potential that cannabis use has to burden the health, social welfare, and criminal justice systems. 8

Methods
Given that cannabis has been available in South Africa for many and a national population-based survey in 2005 (SABSSM II). 10 The YRBS was a cross-sectional national prevalence study among secondary school learners in South Africa and consisted of sampling 23 government schools per province, within which 14 766 grades 8, 9, 10 and 11 learners were sampled and 10 699 participated. 9 The survey was planned using a two-stage cluster sample design so as to ensure nationally and provincially representative data collected through selfadministered questionnaires. SABSSM II is a national household study of HIV/AIDS that gathered data on HIV prevalence, behaviour and communication. 10 The survey design applied a multi-stage disproportionate, stratified sampling approach that

Lifetime use of cannabis
As can be seen in Table I, among adolescents, lifetime cannabis use for girls (7%) has been similar among Cape Town 11,12 and national 9 adolescents from 1993 to 2002, while there has been an increase among boys from 13% to 20% over the same period.
The onset of using cannabis was found to be 4% for those under the age of 13 years in the 2002 YRBS as can be seen in Table I. In a national study among educators older than 20 years (N= 20 626) still lower current cannabis use rates (0.3%) were found (0.6% for males and 0.1% for females). 26 Current cannabis use among adults was found to be 2% (4.4% among men and 0.3% among women) in 2005. 10 The prevalence rates of 4.4% among men and 0.3% among women for current cannabis use are lower than those in some other countries such as the USA, with current cannabis use of 8.2% among men and 6.1% among women 12 years and above, 27 and 8.9% among men and 4.6% among women 14 years and above in Australia. 28 Annual cannabis prevalence rates are lower in South America (2.6%), Asia (2.1%) and higher in West and Central Europe (7.4%), Africa (8.1%), and North America (10.3%), USA (31%). 4 Among adults in South Africa higher current cannabis use rates were found in urban (2.3%) than in rural (1.0%) areas in 2005. 10 Among youth (15 -24 years, N=5 607) current cannabis use was highest among coloureds (6.0%), followed by whites 4.3%, Indian or Asian 1.8% and black African 1.1%. 10 Among adolescents current cannabis use was found highest in the provinces of Gauteng, Western Cape, Mpumalanga, Free State and Limpopo, 9 and it was found highest among adults in Western Cape, Gauteng and North West Provinces 10 (Fig. 1).
The range of current use of cannabis among adolescents from 2% to 9% in two national samples 9,10 seems to be reflected in various surveys among youth, where it ranges from 2.6% to 12%. Male youth had far higher current cannabis use prevalence rates than female youth, as is seen in Table II.

Self-reported cannabis use and urine analysis
Pick et al. 22 studied 1 671 mine employees from 7 mines. Selfreported lifetime cannabis use was 7.2% and current cannabis use 2.3%, while urine analysis found 9.1% current cannabis use.
Plüddemann and Parry 21 found among a sample of approximately 1 000 arrestees tested and interviewed in three major cities in South Africa that only 54% of the arrestees who tested positive for cannabis reported using the drug in the past 30 days.
Consequently, the prevalence rates of cannabis use in previously reported surveys may be seriously underreported and true figures may well be much higher than the reported figures.

Burden of cannabis use Cannabis use and injuries
Various studies in trauma units show high levels of cannabis use preceding an injury. Bowley et al. 23     and other offence (30.6%). 29

Cannabis use and HIV
Based on data from SABSSM II, HIV-positive persons were more likely current cannabis users than HIV-negative persons. 30 Cannabis use was found to be related to having more than one regular partner and to having irregular partners but not to unprotected first or last sex, as seen in Table III below.

Seizures and treatment demand of cannabis
There has been a slight increase in seizures 4  Whether the slight treatment increase is possibly due to increased potency of cannabis used is unknown -South African cannabis is rarely tested for its active chemical, delta-9-tetrahydrocannabinol (THC) levels. Other factors, such as the declining age of the treatment population, may also be responsible. 4 In a recent HSRC study at drug treatment centres key informants reported an increase in cannabis psychosis due to the high quality of cannabis now available as a result of hydroponic cultivation, as can be seen from the following quotes: 31  16 Rural secondary schools 209 11.2 2.6 6.2 Mwansa et al. 15 Bela Bela & Pretoria 303 4 Peltzer et al. 18 Community survey 800 12.4 1.3 6.9 Peltzer et al. 19 University students 799 10.7 2.9 6.6 Peltzer et al. 20 National ,

Conclusion
Cannabis is the most common illicit substance used in South Africa, in keeping with world trends, with particularly high use among the youth. 32 Current self-reported cannabis use was 5 -10% among adolescents and 2% among adults, higher among men than women, higher in urban than rural areas, higher in the urban provinces of Western Cape and Gauteng than the other provinces and higher among coloureds and whites than other racial groups.
The use of cannabis is widespread among all sectors of South African society, and may be seriously underreported. Cannabis is inexpensive, easy to produce, and the law prohibiting possession is infrequently enforced. 32 Cannabis is commonly misused by trauma patients (29 -59%) and is often associated with crime (39%). There has been an increase in seizures and treatment demand for cannabis. The current (2006) treatment demand for the whole country is 17% for cannabis and 3.4% for cannabis and mandrax. The increase in treatment demand has implications for service delivery, especially considering the lack of treatment facilities. 31 One effective way of reducing cannabis-related problems is routine screening and brief intervention of substance (including cannabis) use in primary and emergency care settings.
The National Department of Social Development, South Africa, is thanked for funding this study.