Analytical And Legislative Aspects Of Cannabis

Quit Marijuana The Complete Guide

New Treatment for Cannabis Dependence

Get Instant Access



This first section of Chapter 4 is concerned with forensic definitions of cannabis and its products as a controlled drug of abuse. Three following sections address related offences and attitudes, techniques used in forensic analysis, and the pharmaceutical quality of cannabis products.

1.1 International Conventions and National Enactments

The various international conventions and protocols, and the succession of 'Dangerous Drugs' legislation in the UK, are discussed in this section and summarised in Table 1.

There is a long history of medicinal use and social abuse of Indian Hemp (see Chapter 1) but there were strong representations from some delegations to the 1923 Opium Conference, notably reports of Egyptian experience, seeking to ban all non-medicinal uses. In the subsequent 1925 (and 1931) League of Nations Conventions, the description of cannabis restricted the controlled drug to the female plant and named a particular species, Cannabis sativa, alias indica. In the UK, 'Indian Hemp' was dropped in the 1932 revision of the British Pharmacopoeia 1914 and non-medicinal use was banned in 1928.

This definition was maintained after World War II in the United Nations 'Lake Success' amending protocol, and in the UK in the corresponding Dangerous Drugs Act of 1951, through the wording:

"Indian hemp is the dried flowering or fruiting tops of the pistillate plant known as Cannabis sativa [alt.indica] from which the resin has not been extracted".

In the United Nations comprehensive 'Single Convention' of 1961, which brought together many classes of narcotic and other drugs of abuse, the definition used in Article 1 removed this gender discrimination by describing Cannabis as—

"the flowering or fruiting tops of the Cannabis plant (excluding the seeds and leaves when not accompanied by the tops) from which the resin has not been extracted, by whatever name they may be designated"; where cannabis plant "means any plant of the genus Cannabis".

In a corresponding national enactment, the UK Dangerous Drugs Act (DDA) 1964 recognised this widened scope of control by the crisper wording—

"the flowering or fruiting tops of any plant of the genus cannabis from which the resin has not been extracted, by whatever name they may be designated".

GEOFFREY F.PHILLIPS Table l Conventions and Enactments

(a) Relevant International Conventions and Protocols Convention on Narcotic Drugs: Geneva 1931

amending protocol: Lake Success (USA) 1946 Single Convention on Narcotic Drugs: New York 1961 (mostly natural opiates and synthetic opioids) various amending protocols, e.g. 1972 Convention on Psychotropic Substances: Vienna 1971 Convention Against Illegal Trafficking: Vienna 1988 (international surveillance and precursors control)

(b) Post-1945 Dangerous Drugs legislation in Great Britain

— there are separate series for Northern Ireland, IoM, Channel Isles Dangerous Drugs Act 1951

Dangerous Drugs Act 1964: redefine Cannabis, prohibit cultivation Dangerous Drugs Act 1965: consolidated UN SC/1961

but continued D.D.Regs. 1964 Dangerous Drugs Act 1967:

drug addiction, safe custody, powers of search Drugs (Prevention of Misuse) Act 1964: primarily 'generic' stimulants but added — DPMA, Mod. Order 1966: hallucinogens (semi-generic) DPMA, Mod. Order 1970: repealed broad generic stimulants, and added cannabinoids and some hallucinogens Misuse of Drugs Act 1971: consolidated DDA and DPMA, with effect 1973 various amending Orders including new drugs, and moving drugs between penalty classes Misuse of Drugs Regulations 1973

various amending Order and consolidated as Msuse of Drugs Regulations 1985 and further amending Orders

These extended definitions had the double advantage of bringing into international control the potentially quite potent male flowering tops and also of sidestepping taxonomic argument as to whether cannabis was a monospecific genus (see below, §1.2, and more detail in Chapter 2). The wider legal definition of cannabis was continued in the UK in the DDA 1965—which incorporated other narcotic substances newly specified in the UN 1961 Single Convention—and was further sustained in the consolidating enactment of the Misuse of Drugs Act 1971 (MDA).

In France, the production, marketing and use of "Indian hemp, plant and resin, their preparations; and THC and derivatives" (THC is discussed in §1.5) were prohibited except for research or laboratory purposes; there is reference in §2.1 to the French provision for authority for commercial cultivation of hemp fibre. In the UK, the MDA, s. 7(4), gave power for Regulations under the Act (MDR) to make production, supply and possession of specified Controlled Drugs unlawful (except for specified research purposes): Cannabis was placed on such a list in the MDR 1973 and hence became no longer available in clinical practice.

1.2 Distinction and Confusion of Herb and Resin

The UN Multilingual Dictionary (1983) of psychotropic substances under international control lists 194 synonyms for herbal and 54 for resin forms including beverages, confectionery and other preparations containing cannabis. The most frequently encountered terms, according to the country of origin, are marihuana, bhang, dagga, ganja (*) and kif for herbal; and hashish and charas (*) for resin. Some of those terms (e.g. *) may be used interchangeably for either herbal or resin form.

It has become generally accepted that Cannabis sativa is a monospecific genus but that there are three genotypes:

1. the resin plant is rich (>1%) in THC [q.v.], with significant amounts of CBD [q.v.];

2. the hemp fibre plant has low (<0.3%) THC but CBD is essentially absent;

3. an intermediate variety, growing in certain climates.

In practice, the high and low THC/CBD plant types may co-cultivate in the same area, e.g. some Sri Lankan crops.

In those administrations where national legislation for the control of drugs recognises a forensic distinction between herbal specimens and the derived resin (usually obtained by physical separation from the herb and then compacted), the prosecution charge must specify which botanical form has been detected. There have occasionally been problems of mis-identification between cannabis resin and the herbal form, particularly when the seized material is compacted herb (see below), or constitutes a smoking residue (which aspect is discussed later—cf. §1.6).

Small amounts of badly preserved, friable resin may be difficult for the examiner to distinguish from compressed, finely chopped, resin-rich herbal tops. A court may reject a charge which refers to (herbal) "cannabis" if the evidence submitted identifies it as "cannabis resin", e.g. Jersey Royal Court, 19 November 1969. That the separated resin need not be pure was upheld in the UK on Appeal in R v Janet Thomas (1981), not-withstanding the presence of herbal debris, including intact oil glands, in a compacted resinous mass. In the criterion of 'separated resin', mechanical separation— e.g. stripping of the lower leaves—should be distinguished from chemical extraction or physical crushing. Thus, in R v Berriedale-Johnson (1976) lower leaves were not accepted as constituting 'cannabis resin' [nor would these leaves have qualified—at that time—as herbal cannabis—see following discussion in §1.3].

1.3 Parts of Plant: Fruiting/Flowering Tops; Aerial Parts, Stalk; Seed (Non)viable

Further forensic uncertainty may arise where there is need for legal discrimination of the flowering tops from the axial buds and lower leaves (which may still be a moderate source of cannabinoid congeners). The forensic difficulty experienced in the UK was not a problem in US Federal Law in the 1970s, when the definition of marihuana subsumed flowering/fruiting tops and lower leaf and viable seed. Moreover, the US Drug Abuse Prevention & Control Act [DAPCA] 1970 also had a very much broader description of synthetic variants of "tetrahydrocannabinols"—see discussion in §1.8 below.

In UK law this anomaly could not be resolved simply by tabling a new statutory 'Modification Order' because the 'Cannabis' definition was contained within the body of the MDA—unlike most other 'dangerous drugs' which were substances and products described in the appended Schedule 2 which is accessible to amendment by an 'Affirmative Resolution' in parliamentary debate. Accordingly, the definition in the principal act, the MDA itself, had to be amended in respect of the cannabis definition. This was conveniently achieved by inserting an additional section [s. 52] among a variety of general amendments to the criminal law that were collated in the Criminal Justice Act of 1977. Herbal cannabis, after excluding the resin, was thereby redefined as—

"all the aerial parts, except the lignified stem and the non-viable seed, of any plant of the genus Cannabis".

Note that this new definition deliberately excluded the roots from control under the MDA.

This revision in the UK in 1977 was forced because previous attempts to control herbal material other than flowering or fruiting parts, such as lower leaf and stalk, could not necessarily rely on demonstrating to the Court the presence within the herbal material of controlled 'cannabinoids' (see below, §1.7 for discussion of controls on congeneric substances constituting the active principles of the herb). After a variety of rulings in lower courts, the link between these other parts of the plant and the 'cannabinoids' controls was finally tested in a key judgment in the House of Lords. Thus, in the case of R v Goodchild (1977-78), itself following two Crown Court hearings and two Appeals, their Lordships ultimately ruled that leaves and stalk which had been separated from the harvested plant did not constitute the separated resin and nor were these other parts of the plant legally equivalent to those cannabinoids naturally contained within them (which substances were listed in a controlled drug category attracting a higher level of penalty—see §1.5 and §1.7 below).

1.4 Compendial Definitions

The British Pharmacopoeia 1914 edition was the last to provide a monograph for cannabis; the 'Characters' and 'Tests' are described in §4.1. This monograph defined "Cannabis Indica", alias "Indian Hemp", as the—

"dried flowering or fruiting tops of the pistillate plant Cannabis sativa Linn."

and added "grown in India, from which the resin has not been removed".

The British Pharmaceutical Codex 1949—the last BPC to contain a Cannabis monograph—retained only the first part of the BP 1914 definition (i.e. no reference to origin or to removing resin) but added "(Fam. Cannabinaceae)". This edition of the Codex also prescribed recipes for preparation of (alcoholic) Extract of Cannabis and the appropriate dilution to make Tincture of Cannabis.

The Japanese Herbal Medicines Codex and the Chinese Pharmacopoeia have current monographs for 'hemp fruit' and 'Huo Ma Ren' (i.e. marihuana) respectively: see §4.1 later.

1.5 Cannabis Oils

In the UK, the 'Controlled Drugs' listed in Schedule 2 to the MDA 1971 are subdivided between 'Parts' I, II and III, respectively containing drugs of 'class A', 'B' and 'C', largely following the classification in Schedules I-III in the UN Single Convention 1961; this distribution sought to strike a balance between the perceived degree of social harm and the medicinal value of the substances. In Schedule 4 to the MDA, direction is given for the prosecution and punishment of various relevant offences (cf. §2 below) and a descending scale of penalties reflects the allocation of substances between classes A, B and C. A fourth Part of MDA Schedule 2 provides legal definitions for those entries in Parts I-III of Schedule 2 that do not admit exact chemical composition.

'Cannabinol derivatives' are listed in Part I, i.e. are controlled as 'class A' drugs and explicitly defined in Part IV (see full definition in §1.7). This definition carries the exclusion "except where contained in cannabis or cannabis resin". The latter natural products were already listed in Part II and thus attracted the lower penalties of class B drugs. Following the revised definition of 'Cannabis' in s. 52 of the Criminal Law Act 1977, the herbal form of the drug thereafter legally subsumes "all aerial parts" (except lignified stem and non-viable seeds) of the plant.

In the DDA 1965, following on the UN Single Convention 1961, 'Any extract or tincture of cannabis' (as exemplified by, but not limited to, the alcoholic preparations of the BP 1914 and BP Codex 1949) were listed in a subsequent clause in the schedule containing 'Cannabis' and its resin. These named preparations were deliberately omitted from Schedule 2 of the MDA 1971 and control of 'extract' or 'tincture' thereafter rested on a general reference to "preparations" (of the appropriate class of drug).

The more or less concentrated 'Cannabis oil' is a solvent extract containing 2040% of the potent principal cannabinoid, tetrahydrocannabinol (THC), and just occasionally, appreciably higher concentrations are detected (cf. Figure 2, later). If judged by UK seizures, so-called hash oil exported from the 'resin belt' countries (i.e. Indian subcontinent, Middle East, Morocco) often contains three or four times the common local level (say, 5-15%) of THC in resin from that region; whereas liquid cannabis preparations from the Caribbean and East Africa may represent tenfold concentration of the much lower level (say, 1-3%) of THC in local herb. Some recent seizures (King, 1997) of the oil appear to derive from extraction of intensively cultivated herbal cannabis. Cannabis oil may be clandestinely prepared, from either herbal or resin forms of cannabis, by extraction with ethyl or methyl alcohol in, for instance, a large drum. The mixture is then filtered and the filtrate concentrated by evaporation of solvent (e.g. in a pressure cooker); it may be purified by treatment with petroleum ether.

Cannabis oil was for many years regarded in UK forensic practice as a preparation of THC, a class A drug (see §1.7). However, if a lower potency oil, only comparable in THC content with the Extract or Tincture of the BPC 1949, is supported by collateral evidence of botanical origin, then 'a preparation of a class B drug' is a more appropriate and equitable prosecution charge. If the solvent were entirely removed, the viscous residual product might then be regarded as 'purified cannabis resin', because the MDA 1971, also places the resin—defined in s. 37(1) as the separated resin, whether crude or purified—in 'class B'. However, where forensic practice treated oily extract of herbal Cannabis as a preparation of THC, then the higher penalties of class A would apply. This situation was recognised as anomalous.

The main constituents of the oil are tetrahydrocannabinol (THC) and cannabinol (CBN); but if made from resin, some cannabidiol (CBD) is also present. Accordingly, identification of the presence of CBD permits assumption of a resin source, whence in UK law the oil can be treated as 'purified cannabis resin' in 'class B'. But in the absence of CBD, or if a herbal source of the oil is otherwise proved or admitted, then 'a preparation of THC', not being Cannabis, predicates assignment as 'class A'. Such a decision was upheld in the case of R v Carter in Oxford Crown Court in December 1992, when the oil was not accepted as "a preparation of Cannabis".

This discrimination in Britain was widely considered as unreasonable, especially for low concentration 'cannabirum' extracts from the Caribbean, and various options for changes in UK law were considered:

1. Add a new entity 'Liquid cannabis' to Part II [i.e. with class B] and add a new definition to the list in Part IV [e.g. "a product which has been prepared from cannabis or cannabis resin by solvent extraction".]

2. Transfer cannabinol and cannabinol derivatives from Pt. I to Pt. II of Sch. 2 of MDA.

3. Amend Sch. 2 of the MDA as at 2. but maintain the distinction between nontherapeutic and therapeutic Controlled Drugs through Sch. 1 and 2 of subordinate Misuse of Drugs Regulations.

Option 2 was regarded as administratively tidier but it conflicted with the UN Single Convention placement of cannabinoids in its Schedule I and cannabis products in Schedule II. Subsequently, the UN recommended for [potential] medical usage reasons, transferring pure THC {as one potent stereoisomer, under its US and WHO nonproprietary medicinal name 'dronabinol'} from Sch. I to II. This isomer was a clear candidate for the 'medicinal' Schedule, S2, of MD Regulations. Meanwhile, the Home Office Forensic Science laboratories for some years anticipated option 1, by reporting all 'hash oil' samples as 'class B' without distinction as to source, conveniently regarding such specimens implicitly or explicitly as 'purified cannabis resin'.

Firm recommendations to resolve this forensic anomaly were presented in 1996 by the Advisory Council on Misuse of Drugs but legal enactment has had to wait on reference to the new parliament in 1997.

1.6 Smoking Residues

The partially pyrolysed residue in a pipe bowl or cigarette butt may still retain some herbal features but is conveniently regarded as a crude specimen of 'separated resin'. Thus, the act of smoking has thermally 'separated' the resin from (herbal) cannabis. The residue may be richer in THC than the original herb through thermal decarboxylation of precursor acids [see next section] but the quantity (and quality!) present will not usually be sufficient to constitute a dose for further smoking. Morphological examination of uncarbonized material may provide forensic evidence of herbal or intact resin but more frequently this distinction is blurred or inconclusive. Nevertheless, the chemical evidence from the nature and proportion of cannabinoid congeners may be capable of three interpretations:

1. The process of distillation—in pipe ('schaum') or cigarette ('joint' or 'reefer')— has produced purified cannabis resin, i.e. supporting a charge of simple possession of a small quantity of a class B substance.

2. This constitutes evidence of having smoked, and therefore having had prior possession of, a limited quantity of cannabis or resin or preparation thereof. As pointed out by Phillips (1973), two lines may be accessible to defence of such a charge: that the smoking implement at the material (prior) time had been in the possession of some other identifiable person; or that the defendant had smoked a preparation (such as Cannabis Tincture BPC) lawfully dispensed for him (cf. Clarke and Robinson, 1970).

3. In the absence of any vegetative matter, the cannabinoid residue might point to prior possession of a small quantity of cannabinol derivatives: but as discussed in the previous Section, this leads to anomalous case law and potentially inequitable penalties.

1.7 Natural Cannabinoids, Including C3 and Cl Analogues

At least 70 terpenoid phenols and acids have been reported to be isolated from Cannabis. The origin and nature of these congeneric substances have been discussed in Chapter 3. For convenience of discussion of structural variation of the natural congeners (discussed in this Section), the synthetic homologues (in §1.8), their esters (§1.9) and their respective stereochemistries (§1.10), their inter-relationships and principal graphic formulae are illustrated in Table 2. Many of the congeneric substances (originally identified as indicated in Table 2), such as cannabichromene, CBCh (with ring-C open), cannabigerol, CBG (both rings B and C open) and cannbicyclol, CBCy (cyclised to a fourth ring), and their various methyl ethers and carboxylic precursors, are of insufficient psychoactivity to warrant international control as potential drugs of abuse.

In the UK the first specific control of the cannabinoid natural constituents cannabinol (CBN; Table 2, I: R=pentyl) and its tetrahydro derivatives, including the most potent stereoisomer, delta9-trans-THC (Table 2, Ila), was their explicit listing as psychotropic substances in 1970 in an addition to the schedule of drugs controlled by the Drugs Prevention of Misuse Act (DPMA) 1964, thereby anticipating UN proposals in the UN Psychotropic Substances Convention 1971, discussed in §1.8.

The distinction in seriousness of criminal offence between cannabinoid substances and herbal specimens of cannabis was heightened by the MDA 1971, which placed 'cannabinol and cannabinol derivatives' in class A (the highest penalty class) but listed cannabis and its resin (whether crude or purified) in class B, in harmony with the UN classification. A range of hydrogenated 'cannabinol derivatives' was defined in Part IV of Schedule 2 to MDA as—

"the following substances, except where contained in cannabis or cannabis resin, the tetrahydro derivatives of cannabinol and 3-alkyl homologues of cannabinol or of its tetrahydro derivatives"

This definition comprehensively subsumed not only all tetrahydro (structural) isomers [see below for the US DAPCA 1970 legislation on this point], of which the delta9

(alias delta1) and delta8 (alias delta6(1)) (cf. Table 2, Ilia) are the more common, whereas other isomers, such as Adams and Baker's (1940) synthetic delta3, 4 (Table 2, Illb), are curiosities; but it also extends to homologous sidechain derivatives. Thus, replacing the 3-pentyl group by alkyl groups with more than 5 carbon atoms thereby brings into control the synthetic 3-alkyl homologues of CBN and THC (see §1.8).

Table 2 Cannabinoid congeners and structurally related dibenzopyrans and chromenols

Table 2 Cannabinoid congeners and structurally related dibenzopyrans and chromenols

Cannabis Isomers


However, note that the naturally occurring congeners of CBN and THC with shorter 3-alkyl sidechains, the cannabivarins (CBV and THV), each with a 3-propyl group (Table 2, I and Ila: R=propyl), and cannabiorcinols, each with 3-methyl (Table 2, I and Ila: R=methyl), cannot be construed as 'homologues' of CBN and THC respectively (which have the longer 3-pentyl substituent). Accordingly, the natural cannabivarins and cannabiorcinols are not controlled by the 'homologues' extension in the MDA definition.

The acid precursors of CBN and CBD, such as cannabinolic acid (CBNA) and cannabidiol carboxylic acid, and the tetrahydro derivatives THCA(A) (2-COOH) and THCA(B) (4-COOH), occur naturally in cannabis extracts. These acids are not controlled as such in the UK—but as previously noted [§1.6] thermal decarboxylation (e.g. during smoking) generates additional CBN and THC and thus these acid precursors ultimately contribute to the potency of the cannabis specimen when smoked. Variation in THCA/THC ratios in cannabis specimens of different geographical origin is discussed in §3.6 and some data are summarised in Table 6.

1.8 Synthetic Analogues of Natural Cannabinoids

The DPMA of 1964 was initially designed to control stimulant and anorectic drugs, which in the early 1960s were becoming a distinct public nuisance. These substances were structurally related to amphetamine, but were not subsumed by the UN Single Convention 1961 nor in the UK by the DDA 1965. In the UK in 1966 the DPMA was taken as a convenient vehicle for control of hallucinogens, such as dimethyltryptamine (DMT) and the very potent lysergide (LSD). Concurrent international discussion in WHO and UN working-parties reviewed many classes of psychotropic substances that were not included with the primarily narcotic drugs in the UN Single Convention 1961; and led to the interim Psychotropic Protocol and ultimately to the creation of the Psychotropic Substances Convention 1971. One of the groups of psychedelic drugs which the WHO recommended for control was the series of synthetic analogues of THC, particularly the so-called 'synhexyl', the 3-hexyl homologue of THC (cf. Table 2, Ila: R=hexyl).

This recommendation was reflected in a definition incorporated in UK legislation in 1970 under the DPMA 1964 and was later consolidated in the S2-Part IV definitions of the MDA 1971 [as set out in §1.7 above]. It should be noted that branched 3-alkyl sidechains (such as 'synhexyl') qualify for control thereby but that derivatives with 3-substitution by alkenyl (ethylenic) or alkynyl (acetylenic) or alkylidene (divalent alkyl radicals) do not qualify for control through this definition.

The US Drug Abuse Prevention & Control Act [DAPCA] 1970 introduced an even broader description of "tetrahydrocannabinols":

"Synthetic equivalents of the substances contained in the plant, or in the resinous extractives of Cannabis sp., and/or synthetic substances, derivatives, and their isomers with similar chemical structure and pharmacological activity"

and then gave as non-exclusive examples—

"such as the following, delta1 cis or trans THC and their optical isomers, delta6 cis or trans THC and their optical isomers, delta3, 4 cis or trans THC and their optical isomers, and since nomenclature of these substances is not internationally standardised, compounds of these structures regardless of numerical designation of atomic positions".

This conflict in nomenclature of the natural cannabinoids stemmed from investigative degradation to, and early synthesis from, monoterpene components. The locants on the non-aromatic ring (of THC and CED) (cf. ring C in Table 2, IV) were historically prescribed in monoterpene convention (Table 2, V); the ring attachment for CBD was then placed at locant '3' and ring fusion for THC at locants '3, 4'. When fully systematic (IUPAC and Chem-Abs approved) nomenclature was applied to substances of the cannabinoid family, they were regarded as derivatives of dibenzo[a, c] pyran: then conventionally orientating the dibenzopyran with ring A top right and using its prescribed clockwise numbering system, the ring B oxygen and the dimethyl substituents are given locants '5' and '6' respectively, and the monoterpene carbon bearing the methyl, previously '1', becomes position '9' and erstwhile '6' becomes '8'.

In addition to these early experimental substances, more recently a number of related structures have been synthesised by the pharmaceutical industry and have been screened for potential clinical use. Table 3 lists eight such substances for which WHO non-proprietary names have been assigned, together with their various clinical indications. Seven retain the cannabinoid characteristic oxatricyclic system, five being modified dibenzopyrans and two, Nabitan and Tinabinol, as aza—or thia-analogues respectively. The eighth new drug, Nonabine, at least retains an oxabicyclo (chromenol) moiety. Another commonality resides in their respective 3-alkyl groups: Pirnabine has the simple methyl of the natural orcinol series, whereas the other seven have a homologous nine-carbon branched chain alkyl substituent. Their respective potential clinical uses, as indicated in Table 3, are somewhat varied but closely reflect the different medical applications of natural cannabis—see summary in §2.4 and the extensive treatment in Chapters 7 and 8.

The synthetically prepared selected single stereoisomer (-)-trans-THC (cf. discussion of cannabinoid stereochemistry, and legal implications, in §1.10) has been assigned the WHO non-proprietary name 'Dronabinol' and is marketed in USA. It has been included in Table 3 for comparison; quality issues, including the USP monograph, are described in §4.8.

1.9 Esters of Cannabinoids

In the UK, control of naturally occurring esters, such as the O-acetates of the phenolic functions of CBN and THC (cf. Table 2, V: OX=OAc, R=pentyl), is achieved through the 'esters' extension clause in Part I of MDA S2, which bites wherever a class A drug

Table 3 Synthetic dibenzopyran drugs with clinical potential: names, structure and CAS no., control status and indication, 'BAN'=British Approved Names 1994 list and supp.; 'USAN'=United States Adopted Names 1994 list and supp.; 'pINN' and 'rINN'=Proposed and Recommended lists of WHO non-proprietary names


USAN pirnabine

status: not CD anti-glaucoma (SISA Inc) 0-acetyl-A6a> 10*-tetrahydrocannabiorcinol tranquiliser and anti-emetic

(Lilly 'Cesamet' 1983)



Me anti-hypertensive (Lilly 'Nabidrox') (±)-3-(l, 1-dimethylheptyl) homologue of 9-demethyl-9 RJ-hydroxyhexahydro-cannabinol status: MDA classA-ester of 3-alkyl homologue of THC anti-convulsant (SISA Inc)

anti-hypertensive (Lilly 'Nabidrox') (±)-3-(l, 1-dimethylheptyl) homologue of 9-demethyl-9 RJ-hydroxyhexahydro-cannabinol status: MDA classA-ester of 3-alkyl homologue of THC anti-convulsant (SISA Inc)

Y" = 4-(perhydroazepin-l -yl)butanoyl ester of 3-(l,2-dimethylheptyl)

homologue of A6a' 10a-THC



CAS 16985-03-8 status: not CD anti-emetic (Beechanv 7-(l,2-dimethylheptyl)-2,2-dimethyl-4- (4-pyridyl) chromen- 5-ol

Me homologue of A6a' 10a-THC

Me anti-hypertensive (SISA Inc) 3-(l,2-dimethylheptyl) homologue of 9-demethvl-7-thia- A6a> 10l-THC

Table 3 (continued)

Table 3 (continued)

Diary Wimpy Kid Activity Pages

is capable of forming an ester (or ether). Thereby, all such esters (and ethers) attract similar class A penalties. A more recent uncertainty involved the synthetically prepared acetate and other esters of the cannabinoids which had been detected in an extract of cannabis. Deliberate preparation of the acetate of THC present in an extract of cannabis was ruled in June 1995 as preparation of a class A substance, the product being the ester of the class A substance THC.

In the case before Merthyr Tydfll Crown Court, a significant quantity of alcohol-extracted cannabis, which had been further purified by petroleum ether treatment, was reported by the relevant laboratory of the Forensic Science Service as a 'class B' product; whereas residues of acetic anhydride containing small amounts [ca 150mg/ 220 ml] of THC acetate, and also flasks containing solid residues of THC acetate, were both reported as 'an ester of a class A drug', that is to say as an ester of THC. The alternative proposition that the THC acetate present was an ester of an extract of cannabis is not chemically sensible nor indeed is it legally possible—because in the MDA the supplementary clause extending control to 'esters' is only found in Part I of S2 and thus can only bite on esters of class A substances, as such or in admixture. In this case the prosecution submission must be regarded as both morally and legally reasonable.

Thus, 'morally' reasonable because the scale of manufacture did not warrant anticipating forthcoming legislation by unjustifiably assigning the lower penalty class B status to this chemical derivative of hash oil. The defendant's recipe book and his use of acetic anhydride reagent made clear that the acetate was the deliberate target and that the derivative was expected to be at least twice as potent as THC itself. At the very least, the residues were evidence of prior larger scale 'manufacture of a Controlled Drug'.

And 'legally' reasonable because THC acetate should be classified as a class A Controlled Drug in virtue of being an ester of [one or more isomeric] cannabinol derivatives. The fact that the source of the THC from which the THC acetate had been chemically prepared was an extract of cannabis is not relevant and thus whether the starting material had class A or class B status is not in issue. Even if the starting material had been proved to be a class 'B' substance, and then the production of a class A derivative challenged, there are many precedents for retaining their respective classes for derivatives despite chemical conversion—actual or potential—between class B and A drugs; for instance, codeine (class B) is an ether of morphine (class A).

Coincidentally, it was in 1995 that New Zealand police reported their first seizure of THC acetate (confirmed by GC—MS, following various chromatographic separations: Valentine, 1996). Studies in the Institute of Environmental Science and Research in Auckland indicated it to be probable that the seized sample derived from acetic anhydride treatment of cannabis oil.

1.10 Stereochemistry of THC and Legal Implications

It has already been shown (§1.7) that there are several possible double-bond position isomers of THC, of which the 9(10) (i.e. delta9) and the less potent delta8 are more usually encountered. From their graphic formulae (see Table 2, IIa and IIIa: R=pentyl) it is evident that two series of stereoisomers, geometrical and optical, are also possible.

At the C:B rings junction, there may be cis or trans configurations of the two H's (which have IUPAC locant numbers 6a and 10a. It is stated that the delta9 trans isomer (see Table 2, IIb) is the more potent. These same two carbons, 6a and 10a, are chiral centres so that enantiomeric pairs of optical isomers may exist for each centre. In Table 2, trans structure (IIb) has a pair of enantiomers, RR and SS; and the corresponding cis enantiomeric pair (IIc) have the RS and SR configurations.

In UK law, all possible stereoisomers of a 'Controlled Drug' are automatically controlled in the same way (in virtue of a stereoisomers extension clause in each of Parts I, II and III of S2 of the MDA), unless explicit provision is made for a named stereoisomer to be treated differently. As an example the useful cough remedy 'Phenyl-propanolamine' is explicitly exempted from the MDA control on its diastereoisomer 'Cathine'. It follows that all four stereoisomers of delta9 THC have hitherto been controlled equivalently in the UK.

In February 1990, the UN Commission on Narcotic Drugs (UNCND) recommended that the particular (-)-trans enantiomer, which is available in restricted clinical use, primarily as an anti-emetic in cancer therapy under the WHO non-proprietary name 'Dronabinol' (cf. Table 3), should be transferred from S1 to S2 of the UN Single Convention. This isomer is marketed in the USA by Unimed as the product 'Marinol' and there was an official monograph introduced in the 2nd (1992) Supplement to USP XXII (cf. §4.8). This isomer is identical with the natural RR-trans-delta9-THC and the UN recommendation had some forensic, analytical and legislative, implications.

The UN Vienna Laboratory and the WHO Expert Committee on Drug Dependence considered that rescheduling all four stereoisomers of delta9-THC (viz. RR and SS -trans and RS and SR -cis), would avoid the difficulty of making forensic distinction between an RR form placed in a different schedule from the other 3 stereoisomers [and which, as explained above, in UK law would normally be subsumed with the named isomer unless otherwise specified]. In the sequel, the UNCND decided only to reschedule the RR isomer but individual states party to the Convention may at their option set or retain a more stringent level of control but must not relax controls below that prescribed in the Convention.

The United States Code of Federal Regulations reproduces the revised schedules of the DAPCA 1970 (cf. §1.8). In the second schedule, used for clinically useful controlled drugs, there is a new Part (f) for hallucinogenic substances, which now includes nabilone and sesame oil preparations of (synthetic) dronabinol.

With similar intent, in 1995 the UK amended their Misuse of Drugs Regulations 1985, specifically naming 'Dronabinol' in S 2 of the Regulations and concomitantly removing it and its stereoisomers from the list of drugs designated under s. 7(4) of the MDA 1971 as having no therapeutic value. These two changes enable any stereoisomer of delta9 THC to be used in medical practice in the UK. It should be noted that although by the same statutory order the entry for 'cannabinol derivatives' in S1 of the Regulations was modified by adding the qualification "not being dronabinol or its stereoisomers", there has been no change in the S2: Part I status of delta9 THC under the principal Misuse of Drugs Act: unlawful possession, supply and import of THC continue to attract class A penalties.

To summarise the various levels of control on different cannabis products, Table 4 sets out the schedule status or equivalent in the UN Single Convention (as amended), in UK law, and in certain other national administrations.

2 OFFENCES 2.1 Cultivation

In the UK since the DDA 1964 the unauthorised cultivation of any plant of the genus Cannabis has been a criminal offence. S.I2 of the Misuse of Drugs Regulations 1985 provides authority to grant licences, and set conditions, for the lawful cultivation of plants of the genus Cannabis.

In France, Art. 5181 of the Code de la Santé Publique prohibits cultivation of the resin plant but can authorise cultivation of the fibre variety for specified commercial purposes. The product of the fibre plant is defined as less than 0.3% THC as determined by gas chromatography.

In the UK, for a prosecution to succeed, it must be established that the accused knowingly cultivated the plant(s). S.28 of the MDA provides some statutory defences. Thus, in s.3(b) there is opportunity for acquittal if it can be shown that the defendant had no reason to suspect that the substance was a controlled drug. For instance, consider a defence submission that cannabis grew adventitiously from viable hemp seed components scattered from bird cage litter: this defence could be refuted if the scale of cultivation, or evidence of involvement in husbandry of the crop, were established. However, a plea by an immigrant of Central European origin that the 'weed' [sic!], grown from bird seed scattered in the cabbage patch of her South London

Table 4 Controls on Cannabis and Related Products and Substances







(see Note 3)


herb and resin

1961 (S2)

class B/Sl

class B

Schedule 1(d)


1961 (S2)

class B/Sl

class B

Schedule 1(d)

THC concentrate

1971 (SI)

class A/SI

class B

Schedule 1(d)



class A/SI

class B



'all isomers'



'isomers and derivatives'

1971 (SI)

class A/SI

Schedule 1(d)


1993 (S2)

1995 class A/S2

class B

Schedule 11(f)

Carboxylic acid



class B



Homologues, 3-alkyl

Synhexyl and



Schedule 1(d)

DMHP named

class A/SI

class B

Note 1: Class A of the UK MDA primarily differs from class B in maximum penalty on conviction; but there is also a chemico-forensic difference in that the UN 1961 Convention clause, which generically extends control to esters or ethers of controlled substances, in the MDA only applies to class A substances.

Note 2: Substances listed in the UK Misuse of Drugs Regulations 1985 (MDRegs.) Schedule 1 (i.e. those not in medical use) and in section 1 of Schedule 2 (which are or might have been medically useful) are both drawn from substances in the MDA calss A; while MDRegs. Schedule 2 section 6 substances are mostly drawn from MDA class B.

The same MDRegs. 14, 15, 16, 18, 20, 23, 25 and 26 apply both to S1 and to S2 (s.1); additionally, Reg. 21 provides a small derogation in record keeping at sea, on oil rigs and for midwives for S2 substances.

In 1995, a9-THC (as dronabinol and its stereoisomers) was transferred to S2 of MDRegs. but remains in class A of MDA.

Note 3: The US Drug Abuse Prevention & Control Act 1970 (DAPCA) had five schedules and parts within schedules, which are periodically updated. Part (d) of schedule I lists 'hallucinogenic substances' and the entry for 'tetrahydrocannabinols' is cast in very wide terms [the full text is given in Section 1.8 of this Chapter]. Homologues of THC are subsumed where they are substances, which have 'similar chemical structure and pharmacological activity'. Dronabinol, as a9-THC prepared in capsules, and nabilone, are in a new (hallucinogenic) Part (f) of schedule II.

garden, served as an effective repellant for cabbage pests, in the absence of any evidence of harvesting the 'weed', was accepted without penalty beyond seizure and destruction of the Cannabis crop.

In the UK Cannabis will grow comfortably out-of-doors, in Southern England to a considerable height, although not providing a very high quality product. Even within the Arctic Circle, during UN trials in Northern Norway, successful growth up to about 1 metre was achieved but no resin was formed. As reported in Chapter 2, maximal growth occurs in the Mediterranean area, and in Asian and American subtropical regions, as well as in most of the African continent. These then are the likely areas of origin of clandestine trafficking in the drug product, as discussed in the next section; forensic chemotaxonomic differences are reviewed in §3.7.

Greenhouse cultivation in a climatic temperate zone is usually successful, including the official chemotaxonomic trials described in §3.7. Intensive, forced (usually hydroponic) cultivation may give high yields of good quality crop but makes heavy demands on electric power consumption—which is usually the first clue in detecting its unauthorised use. Much of the supply of high quality plants, so-called 'Skunk', derives from the Netherlands. In October 1995, a 'Restricted' publication by the National Criminal Intelligence Service reviewed increasing illegal cultivation in the UK, clandestine growing techniques commonly encountered, horticultural equipment employed and its legitimate sources, and forensic sampling procedures.

The legal situation is complex and raises interesting issues: the supply of cannabis seeds and the sale of cultivation equipment are not, separately, unlawful; the incitement of others to cultivate the plant and to produce cannabis is an offence but it would be a defence to provide written warning that unlicensed cultivation was unlawful. Following extensive police investigation in 1994-95 of clandestine cultivation in Wales and in southern England, three directors of two, linked, companies advertising and separately selling heating lamps and hydroponic growing equipment, and viable cannabis seeds, pleaded guilty at Newport (Gwent) Crown Court to "incitement to produce a controlled drug". The first successful prosecution of the author and publisher of a book offering explicit advice on the domestic cultivation of cannabis was at Worcester Crown Court in February 1996: he was convicted of incitement of others to cultivate cannabis and also of harvesting his own extensive planting (reported in The Guardian, 19 March 1996).

2.2 Trafficking Offences

Most of the Cannabis illicitly available in countries outside the main producer regions will therefore be the result of unauthorised importation, whence enforcement will be initially a function of national Customs administrations. In the UK, the Customs & Excise Management Act 1979 distinguishes between "knowingly evading a prohibition on import [or export]" and the incomplete act of "attempting to commit an offence" by some deliberate preparatory action that falls short of the actual evasion. The issue may turn on whether there is a general intention to smuggle drugs or the suspect meant to smuggle a specific substance. It is a test of the "guilty knowledge" of the courier.

Following an Appeal Court decision in 1975, in the case of Houghton v Smith, that "to attempt the impossible" was not an offence, intentions to smuggle cannabis (and other drugs) for which substitutions had been made, have been subject to the Criminal Attempts Act 1981. However, this may not apply in charges arising from "handling" goods which are shown subsequently not to have been stolen (cf. the House of Lords ruling in Anderton v Ryan, 1985).

The success of enforcement by national Customs administrations will depend on a number of factors. Packages of herbal cannabis, or blocks of the separated resin, occupy substantial volume (and mass) in contrast to the size of consignments of high value potent synthetic drugs, and therefore larger volume concealments tend to be investigated. For countries such as Ireland and the UK, with extensive highly convoluted coastlines, clandestine landings from small craft have vied in frequency with the long favoured land-boundary mechanism of concealed compartments in lorries and caravans. The growth of mixed goods packaging in commercial freight containers, for road or rail movement, has been a popular alternative. Some approaches to detection of cannabis in such concealments are mentioned in §3.1.

Air traffic, once a major route of importation of cannabis, is now more favoured for low volume, high value, drugs. However, the unpleasant problem of internal concealment has been a frequently used mechanism of trafficking from certain disadvantaged regions of the world; see §3.1.

The UK Drug Trafficking Offences Act 1986 introduced some additional offences, such as the unlawful sale of articles for administration or preparation of a Controlled Drug. Of particular interest (and some dispute) is the power for seizure of assets of a convicted smuggler where these could not be shown not to have been the proceeds of drug trafficking. Here, the onus falls on the duly convicted smuggler to prove legitimate acquisition of discovered substantial assets.

2.3 Dealing, Handling and Possession

1 Unlawful Possession

Possession without lawful reason, is an 'absolute' offence and thus is the most straightforward offence to prove. Custody by another person may also be deemed possession by the accused where it can be successfully demonstrated that the drugs were held for and on behalf of him. Lawful reasons for possession include production, supply or possession of drugs licensed for use in scientific research or laboratory testing, when being used as such. In those countries where medical use is authorised, the preparation, dispensing and administration of therapeutic presentations of cannabis may be lawful, as well as the corresponding possession by a patient for whom such a preparation has been properly prescribed.

Individual national administrations may establish guidelines, or enact statutory levels, of what may be reasonably claimed to be a "personal supply". As a rough guide, a few grams per week may be taken for recreational purposes, and up to 20 g/ week by a habitual or heavy abuser. The charge of unlawful possession constitutes about 85% of cannabis offences in the UK. However, about half of possession cases may be dealt with by formal police "caution" and more by a "suspended" custodial sentence, so that only 10% of such offenders go direct to prison. HM Customs will often impose a "spot fine", and concomitant seizure of the cannabis, when the quantity is small and admitted.

In some other European states, cannabis abuse is so much part of their culture (e.g. in Holland, Italy and Spain) that charges may not be brought for possession of very small quantities. The German Constitutional Court on 28 April 1994 ruled to discontinue prosecution of individual persons arrested for possession of "small amounts" of cannabis stated to be for that individual's personal use [quoted in Le Monde, 2 May 1994, p. 8].

Where no lawful reason for possession is established, the nature of the seized substance or product must be unequivocally determined (cf. §3) and continuity of the evidential chain of samples maintained in order to sustain the connection between the accused and the extent of his control over the place where the drugs were found— e.g. on his person or in his clothing, luggage, home or vehicle.

2 Possession With Intent to Supply

Possession with intent to supply, to be substantiated, essentially rests on scale: is the amount of cannabis product discovered consistent with a claim of 'personal use? Above such levels, some collateral evidence—preferably recorded—is needed of unlawful contact of the suspect with known or putative users of cannabis products.

3 Unlawful Supply

Unlawful supply, or 'dealing', in addition to the facts of quantity and recorded contacts, requires some evidence of the actual transfer of drugs to the control of another person and, usefully, observation of his receipt of payment of some kind for the supply. The proof of supply is crucial because under the MDA the maximum custodial sentence (on indictment in a Crown court) for preparation or trafficking or dealing in cannabis products is 14 years, whereas for simple possession of cannabis the maximum penalty is 5 years (7 years for cannabinoids).

In the UK, in virtue of the MDA s.23(2), civil police have powers to "stop and search" a suspect person, or any vehicle or vessel, when the officer has "reasonable" grounds for suspicion "that the person is in possession" of, or the vehicle contains, a controlled drug. Officers of HM Customs traditionally have still wider powers under their warrant to enter any premises where they have reason to believe they may find smuggled goods of any kind.

4 Usable/Measurable Amounts

A variety of UK case law addresses the de minimis concept. In R v Worsell (1969) unweighable droplets of heroin, barely seen in a tube, were held not to constitute an effective dose for use or sale; but in R v Graham (1970), it was accepted that the defendant had weighable scrapings of cannabis in his pockets. In Bocking v Roberts, as little as 20 micrograms of cannabis resin residue in a pipe, estimated colormetrically, supported conviction on Appeal; but in R v Colyer (1974) the same minute amount in a pipe residue was not considered a measurable quantity within the defendant's knowledge. On appeal, in R v Carver (1978), it was established that 20 micrograms residue in a smoked 'roach' and 2mg cannabis resin scraped from a box constituted an unusable amount and would not support a charge of possession, although it might provide (collateral) evidence of prior possession. However, in the case of R v Boyesen (1980), while the Appeal Court criticised prosecution on minute amounts, the House of Lords ruled (1982) that usability was not an issue: quantity only matters in there being a sufficiently measurable amount for establishing identity of the drug and guilty knowledge of it by the defendant.

5 Prior Possession

The residual unmeasurable droplets of heroin in the Worsell case (above) would have been admissible evidence in a charge of prior possession. Similarly, while the smoke generated by a person smoking cannabis does not constitute 'cannabis' (but does contain cannabinoids controlled in a higher penalty category!), it can provide evidence of prior possession. Metabolites (unless separately 'controlled') in the accused person's urine (or blood) do not constitute possession of a controlled drug—but their presence will reveal prior consumption (cf. evidence of amphetamine taken, in R v Beet, 1977). Such metabolites may not uniquely point to one drug but may be characteristic of a family of substances, e.g. opioid derivatives arising from legitimate medicines such as codeine. Presence of metabolites in urine may also be a signal of leaching from an internal concealment, i.e. a carefully packaged drug that has been inserted in a body cavity or has been swallowed. In these circumstances, sensitive diagnostic tests will reveal a decline in metabolites if a drug (medicinal or abused) has been taken conventionally, whereas pharmacokinetic equilibrium (or, in clinical emergency, a rise in concentration) provides evidence for detention of the suspected courier for personal investigation (cf. §3.1).

2.4 Control of Premises Offences

In UK law, for charges which relate to premises on which drugs are packaged for export, or prepared, supplied, consumed or smoked, to succeed the owner must be knowingly in control of the premises at the material time. This concept of being 'knowingly' in control of premises did not apply prior to 1973, e.g. in the case of Miss Sweet, an Oxford landlady, when in her absence her premises were used for smoking cannabis. If a kitchen, say, is used by other persons for preparing a controlled drug, the owner of the kitchen must be proved to be aware of their intended purpose if to be convicted of control of premises used for that purpose. S.13 of the MDRegs. 1985 provides for the smoking of cannabis or cannabis resin for the purposes of research on premises officially approved for that purpose.

Similar considerations (of being knowingly in control) apply to allowing premises to be used for the cultivation of cannabis or otherwise for the production of a controlled drug.

2.5 Social Attitudes and Public Perceptions

1 National Surveys

Surveys of cannabis usage have been produced in many countries. These address frequency of recreational use, distinction of gender or occupation of user, and form of drug abused.

Significant debate in the United Kingdom on abuse of cannabis may be said to have begun a century ago with the exhaustive report in 1894 of the British Indian Hemp Commission. Since then, recreational use of cannabis has become by far the greatest non-medicinal usage of any controlled drug in the UK. Smoking cannabis is recognised as a leisure activity in a significant cross-section of younger people. It seems likely that one third of the population in the 16-29 age range have "tried" cannabis at some time (Ramsay and Percy, 1996), compared with 14% for amphetamine, 9% for lysergide ('LSD') and 6% for MDMA ('Ecstacy'). The same survey contrasted 43% (50% male, 35% female) of that age range who had tried any prohibited drug at some time in their life, with half that proportion (22%) in the 3055 age group. Cannabis was involved in about 80% of the 115,000 drug seizures in 1995, and in most of the 82,000 'possession' offences (Anon, 1996). Of these cases, 52% resulted in a 'caution', in 22% a fine was imposed and 8% a custodial sentence. Using multivariate analysis and constructing regression models, it appears that cannabis use in the 20-29 age band correlates with a white or Afro-Caribbean (but not Asian) male, spending his evenings out in pubs or elsewhere, and frequently unemployed and living alone in poor housing.

In Spain, a national survey in 1980 (Rodriguez and Anglin, 1987) revealed that 20% of the population aged over 12 had tried cannabis "at some time" and 5% "regularly". In a follow-up survey in 1985 the proportions were 21% "at some time" and 12% weekly or more frequently. Between 1974-1984, university users in Barcelona doubled, from 9.6 to 20%; in Oviedo in 1986 (Lopez-Alvarez et al., 1989), 7% had used it in the previous month and 17% in the previous year. An even choice of product was noted in another university survey: in Valencia in 1975, 10% favoured herb and 12% resin.

In Mexico, a twice-yearly survey "Information Requirements System on Drugs" (Ortiz, et al., 1989), reported that of 16-19 year-olds in 1986, 64% had experimented with cannabis and 42% admitted regular use. Only solvent abuse had comparable popularity in this age range; the cannabis users were mostly male and from the lowest socio-economic class.

Gender-based selection was also noted in a study by Pela (1989). He reported that smoking cannabis was an essentially male phenomenon for Nigerian students in the 1960s and 1970s, whereas in the 1980s, perhaps reflecting a changing view of female education, use of cannabis by women was increasing, although taken usually by the oral route, e.g. the herb in soups and the oil in fizzy drinks. Studies of usage in other African countries may be found in Asuni and Pela (1986).

University experience in Central India was researched by Khan and Unnitham (1979). In a self-reporting survey of 4,300 students at 27 colleges in Jabalpur, 6.3% favoured 'bhang' [herb] in food while 2.1% smoked 'ganja' [resin] or charas; former use was admitted by 10.3 and 2.9%.

In contrast, in Malaysia in the 12 years from 1975 to 1986, heroin was by far the most available drug of abuse (80%), with much less cannabis seized, and synthetic drugs were very uncommon. This is not surprising, given the geographical proximity to South East Asian sources, but penalties for trafficking are very severe. Their National Drug Abuse Monitoring System recorded that during this period known addicts rose 11-fold, from 68 to 755 per million inhabitants.

For the same decade in Singapore, seizures of cannabis products and of opiates and opium, in 1975 were 196 and 667 respectively, representing 22% and 74% of all drugs of abuse. In 1986 the corresponding proportions were 790 (26%) and 1891 (61%). Fuller data are given in Dutt and Lee (1991).

2 Substitution of Cannabis Products

Deliberate substitution of alternative drugs of abuse can become a serious social problem. In Italy in 1974 cannabis disappeared from the market and was rapidly replaced by heroin. At about the same time, when police activity in Stockholm caused supplies of stimulants to dry up, heroin began to appear in Sweden (Hartnoll et al., 1989).

In undisclosed substitution, the comminuted herbal material most frequently passedoff as cannabis is henna. Following a (temporary) decline in 1975 in illicit cannabis imports to the UK, there were some large interceptions of 'fake' resin: one of 40 kg wholly comprised compacted hanna (LGC, 1976). Herbal simulations reported at that time included one based on hops, and an ingenious presentation of stinging nettles steeped in cannabis oil, with added bird-seed to give the product verisimilitude. Coffee powder and chopped parsley have also been substituted, and even Datura strammonium (Corrigan, 1979), which no doubt explained Irish reports of atropine poisoning and hallucinations, and similar reports in Great Britain (Ballantyne et al., 1976). Laboratory and field colour tests—see §3.3.3—can distinguish genuine cannabis from simulations (de Faubert Maunder, 1974).

3 Global Seizures

Global patterns reflect the dominance of areas of cannabis trafficking. In Japan in 1985, seizures under the Cannabis Control Act comprised 16.1 kg resin, 104kg herb and 10kg oil (Tamura,1989). The corresponding numbers of persons arrested in connection with these products were 206, 919 and 148 respectively: most were "white-collar" workers and students under severe commercial or academic competitive pressure. This pattern was relatively constant over a 10 year period. The cannabis products were mostly imported from the USA but there was some from local cultivation.

Official laboratory records of analysis of local seizures of drugs of abuse provide similar evidence of global differences. There was a roughly constant proportion of 1:3 for cannabis to opiates in seizures examined by the Singapore Department of Scientific Services: see the summary in Table 5. This pattern is very different from that found in northern Europe. In the Republic of Ireland, reports by the State Chemist for the years 1968-1978 disclose an increase in positive identification of cannabis from just 10 items (ca. 28% of all drugs positively identified) to 525 (82%) in eleven years (Corrigan, 1979). Over the same period, opiates declined proportionately from 63% (23 items, mostly morphine and synthetics) to 9% (57 items) in 1978.

For comparison, import data for England and Wales based on analyses by the Laboratory of the Government Chemist, reveal a roughly constant proportion, but rapidly increasing numbers (and weights), of cannabis products from seizures by HM Customs. Positive identifications of cannabis rose from 154 (77% of all Controlled Drug identifications) in 1969, to 2,581 (76%) in 1978, and, by 1987, 3,797 items (76%) amounting altogether to 16 tonnes of cannabis products. There is a similar rising trend in UK domestic (i.e. police) seizures of cannabis in the later period 1985-95: see Table 5.

Put in a global perspective, seizures (in tonnes) for the year 1988, as reported to 'Interpol' (Gough, 1991g) were: Europe 150 (including UK 43), North America 458, Australia and New Zealand 6.9.

Table 5

National analyses of drug seizures: Cannabis products compared with opiates and opium

Table 5

National analyses of drug seizures: Cannabis products compared with opiates and opium



UK policeb

Eirec -




Cannabis all other

















Was this article helpful?

0 0
Growing Soilless

Growing Soilless

This is an easy-to-follow, step-by-step guide to growing organic, healthy vegetable, herbs and house plants without soil. Clearly illustrated with black and white line drawings, the book covers every aspect of home hydroponic gardening.

Get My Free Ebook


  • allison
    What is the difference between cannabis fruiting and flowering tops?
    7 years ago
  • anton
    Why this cannabis sativa linn banned in india?
    7 years ago

Post a comment