Cannabis

From Wikipedia

Dried flowers from the Cannabis sativa plant. Note the visible trichomes (commonly known as "crystals"), which contain large quantities of THC, CBD and other cannabinoids.
Scientific classification
Kingdom: Plantae

Phylum: Magnoliophyta

Class: Magnoliopsida

Order: Rosales

Family: Cannabaceae

Genus: Cannabis

Species: C. sativa

Binomial name
Cannabis sativa L.[1]

Cannabis indica Lam. (putative)[1]


Cannabis, also known as marijuana[2], marihuana,[3] and ganja (from Sanskrit: गांजा gañjā, meaning "hemp"), among many other namesa[›], refers to any number of preparations of the Cannabis plant intended for use as a psychoactive drug. The most common form of cannabis used as a drug is the dried herbal form.

The typical herbal form of cannabis consists of the flowers and subtending leaves and stalks of mature pistillate or female plants. The resinous form of the drug is known as hashish (or merely as 'hash').[4]

The major psychoactive chemical compound in cannabis is Δ9-tetrahydrocannabinol (commonly abbreviated as THC). At least 66 other cannabinoids are also present in cannabis, including cannabidiol (CBD), cannabinol (CBN) and tetrahydrocannabivarin (THCV) among many others, which are believed to result in different effects than those of THC alone.[5]

Cannabis use has been found to have occurred as long ago as the third millennium B.C.[6] In modern times, the drug has been used for recreational, religious or spiritual, and medicinal purposes. The United Nations (UN) estimated that in 2004 about 4% of the world's adult population (162 million people) use cannabis annually, and about 0.6% (22.5 million) use it on a daily basis.[7] The possession, use, or sale of cannabis preparations containing psychoactive cannabinoids became illegal in most parts of the world in the early twentieth century. Since then, some countries have intensified the enforcement of cannabis prohibition, while others have reduced it.

Contents [hide]
1 History
2 Forms
2.1 Cannabis (herbal form)
2.2 Hashish
2.3 Hash oil
2.4 Kief
2.5 Residue
3 Potency
4 Routes of administration
5 Effects
5.1 Classification
5.2 Medical use
5.3 Long-term effects
5.4 Adulterants
6 Gateway drug theory
7 Legal status
8 Price
9 Truth serum
10 Breeding and cultivation
11 See also
12 Notes
12.1 Footnotes
12.2 Citations
13 Further reading
14 External links


History

The use of cannabis, at least as fiber, has been shown to go back at least 10,000 years in Taiwan.[8] Má (Pinyin pronunciation), the Chinese expression for hemp, is a pictograph of two plants under a shelter.[9]Cannabis is indigenous to Central and South Asia.[10] Evidence of the inhalation of cannabis smoke can be found as far back as the 3rd millennium B.C., as indicated by charred cannabis seeds found in a ritual brazier at an ancient burial site in present day Romania.[6] Cannabis is also known to have been used by the ancient Hindus of India and Nepal thousands of years ago. The herb was called ganjika in Sanskrit (गांजा/গাঁজা ganja in modern Indic languages).[11][12] The ancient drug soma, mentioned in the Vedas as a sacred intoxicating hallucinogen, was sometimes associated with cannabis.[13]

Cannabis was also known to the ancient Assyrians, who discovered its psychoactive properties through the Aryans.[14] Using it in some religious ceremonies, they called it qunubu (meaning "way to produce smoke"), a probable origin of the modern word "cannabis".[15] Cannabis was also introduced by the Aryans to the Scythians and Thracians/Dacians, whose shamans (the kapnobatai—"those who walk on smoke/clouds") burned cannabis flowers to induce a state of trance.[16] Members of the cult of Dionysus, believed to have originated in Thrace (Bulgaria, Greece and Turkey), are also thought to have inhaled cannabis smoke. In 2003, a leather basket filled with cannabis leaf fragments and seeds was found next to a 2,500- to 2,800-year-old mummified shaman in the northwestern Xinjiang Uygur Autonomous Region of China.[17][18]


Cannabis sativa from Vienna Dioscurides, 512 A.D.Cannabis has an ancient history of ritual use and is found in pharmacological cults around the world. Hemp seeds discovered by archaeologists at Pazyryk suggest early ceremonial practices like eating by the Scythians occurred during the 5th to 2nd century B.C., confirming previous historical reports by Herodotus.[19] One writer has claimed that cannabis was used as a religious sacrament by ancient Jews and early Christians[20] due to the similarity between the Hebrew word "qannabbos" ("cannabis") and the Hebrew phrase "qené bósem" ("aromatic cane"). It was used by Muslims in various Sufi orders as early as the Mamluk period, for example by the Qalandars.[21]

A study published in the South African Journal of Science showed that "pipes dug up from the garden of Shakespeare's home in Stratford upon Avon contain traces of cannabis."[22] The chemical analysis was carried out after researchers hypothesized that the "noted weed" mentioned in Sonnet 76 and the "journey in my head" from Sonnet 27 could be references to cannabis and the use thereof.[23]

Cannabis was criminalized in the United States in 1937 due to Marihuana Tax Act of 1937. Several theories try to explain why it is illegal in most Western societies. Jack Herer, a cannabis legalization activist and writer, argues that the economic interests of the paper and chemical industry were a driving force to make it illegal.[24][25][26] Another explanation is that beneficial effects of hemp would lower the profit of pharmaceutical companies which therefore have a vital interest to keep cannabis illegal.[27] Those economic theories were criticized for not taking social aspect into account. The illegalization was rather a result of racism directed to associate American immigrants of Mexican and African descent with cannabis abuse.[28]

Forms
Cannabis (herbal form)

Dried Cannabis flowers in its herbal form.The terms cannabis or marijuana generally refer to the dried flowers and subtending leaves and stems of the female cannabis plant. This is the most widely consumed form, containing 3% to 22% THC.[29][30] In contrast, cannabis strains used to produce industrial hemp contain less than 1% THC and are thus not valued for recreational use.[31]

Hashish

HashishMain article: Hashish
Hashish (also spelled hasheesh) or hash is a concentrated resin produced from the flowers of the female cannabis plant. Hash can often be more potent than marijuana and can be smoked or chewed.[32] It varies in color from black to golden brown depending upon purity.

According to both the "Talk to FRANK" website and the UKCIA website, "Soap Bar", "perhaps the most common type of hash found in the UK", can contain turpentine, tranquillizers, boot polish, henna and animal turds - amongst several other things.[33][34] One small study of five soap-bar samples seized by UK Customs in 2001 found huge adulteration by many toxic substances, including soil, glue, engine oil and animal faeces.[35]

Hash oil
Main article: Hash oil
Hash oil, or honey oil, is an essential oil extracted from the cannabis plant through the use of various solvents. It has a high proportion of cannabinoids (ranging from 40–90%).[36] This oil is also used in the process of making a variety of cannabis foods.

Kief
Main article: Kief
Kief is a powder made from trichomes removed from the leaves and flowers of cannabis plants. Kief can also be compressed to produce one form of hashish, or consumed in powder form.[37]

Residue

Residue collected from a pipeBecause of THC's adhesive properties, a sticky residue builds up inside the paraphernalia when cannabis is smoked. It has tar-like properties but still contains THC as well as other cannabinoids. This buildup still has all the psychoactive properties of cannabis but is more difficult to smoke due to the discomfort caused to the throat and lungs. Cannabis users typically only smoke residue when cannabis is unavailable. Glass may be water-steamed at a low temperature prior to scraping in order to make the residue easier to remove.[38]

Potency
According to the United Nations Office on Drugs and Crime (UNODC), "the amount of THC present in a cannabis sample is generally used as a measure of cannabis potency."[39] The three main forms of cannabis products are the herb (marijuana), resin (hashish), and oil (hash oil). The UNODC states that marijuana often contains 5% THC content, resin "can contain up to 20% THC content", and that "Cannabis oil may contain more than 60% THC content.".[39]

A scientific study published in 2000 in the Journal of Forensic Sciences (JFS) found that the potency (THC content) of confiscated cannabis in the United States (US) rose from "approximately 3.3% in 1983 and 1984", to "4.47% in 1997". It also concluded that "other major cannabinoids (i.e., CBD, CBN, and CBC)" (other chemicals in cannabis) "showed no significant change in their concentration over the years".[40] More recent research undertaken at the University of Mississippi's Potency Monitoring Project[41] has found that average THC levels in cannabis samples between 1975 and 2007 have increased from 4% in 1983 to 9.6% in 2007.

Australia's National Cannabis Prevention and Information Centre (NCPIC) states that the buds (flowers) of the female cannabis plant contain the highest concentration of THC, followed by the leaves. The stalks and seeds have "much lower THC levels".[42] The UN states that the leaves can contain ten times less THC than the buds, and the stalks one hundred times less THC.[39]

According to the "Talk to FRANK" (UK) website:

"Recently, there has been an increased availability of strong herbal cannabis, containing on average 2-3 times the amount of the active compound, tetrahydrocannabinol or THC, as compared to the traditional imported ‘weed’. This strong cannabis includes:‘sinsemilla’ (a bud grown in the absence of male plants and which has no seeds); ‘homegrown’; ‘skunk’, which has a characteristic strong smell; and imported ‘netherweed’...

...it may not be possible to tell whether a particular sample of 'skunk' or ‘homegrown’ or ‘sinsemilla’ will have a higher potency than an equal amount of traditional herbal cannabis

Of course, "homegrown", "netherweed" and "sinsemilla" are not always "strong". The selection of "skunk" strains generally are, although not every strain of cannabis with a "characteristic strong smell" can be accurately named "skunk". "Traditional herbal cannabis" or "weed", has on the whole, always been subjectively "strong" and thus FRANK leaves his website uncited.[34]

Routes of administration

A Volcano vaporizer. The balloon (top) is filled with vapors that are eventually inhaled.
Cannabis joints are potentially the most harmful method of consumption.
A narrow, screened single-toke utensil, such as the midwakh (shown here) or kiseru, provides small, low-temperature servings, protecting against health damage.Main article: Cannabis consumption
Cannabis is consumed in many different ways, most of which involve inhaling smoke.

The most commonly used include screened bowls, bubblers (small pipes with water chambers), bongs, one-hitters, chillums, paper-wrapped joints and tobacco-leaf-wrapped blunts. Local methods differ by the preparation of the cannabis plant before use, the parts of the cannabis plant which are used, and the treatment of the smoke before inhalation.

A vaporizer heats herbal cannabis to 365–410 °F (185–210 °C), which causes the active ingredients to evaporate into a gas without burning the plant material (the boiling point of THC is 392°F (200°C) at 0.02mmHg pressure, and somewhat higher at standard atmospheric pressure).[43] A lower proportion of toxic chemicals are released than by smoking, although this may vary depending on the design of the vaporizer and the temperature at which it is set. This method of consuming cannabis produces markedly different effects than smoking due to the flash points of different cannabinoids; for example, CBN has a flash point of 212.7°C[44] and would normally be present in smoke but might not be present in vapor.

As an alternative to smoking, cannabis may be consumed orally. However, the cannabis or its extract must be sufficiently heated or dehydrated to cause decarboxylation of its most abundant cannabinoid, tetrahydrocannabinolic acid (THCA), into psychoactive THC.[45]

Cannabinoids can be leached from cannabis plant matter using high-proof spirits (often grain alcohol) to create a tincture, often referred to as Green Dragon.

Cannabis can also be consumed as a tea. THC is lipophilic and only slightly water soluble (with a solubility of 2.8 mg per liter),[46] so tea is made by first adding a saturated fat to hot water (i.e. cream or any milk except skim) with a small amount of cannabis, green or black tea leaves and honey or sugar, steeped for approximately 5 minutes.

Effects

Main short-term physical effects of cannabis.Main article: Effects of cannabis
Cannabis has psychoactive and physiological effects when consumed. The minimum amount of THC required to have a perceptible psychoactive effect is about 10 micrograms per kilogram of body weight.[47] Aside from a subjective change in perception and, most notably, mood, the most common short-term physical and neurological effects include increased heart rate, lowered blood pressure, impairment of short-term episodic memory, working memory, psychomotor coordination, and concentration.[48] Long-term effects are less clear.[49][50]

Classification
Main article: Psychoactive effects
While many drugs clearly fall into the category of either stimulant, depressant, or hallucinogen, cannabis exhibits a mix of all properties, perhaps leaning the most towards hallucinogen or psychedelic properties, though with other effects quite pronounced as well. Though THC is typically considered the primary active component of the cannabis plant, various scientific studies have suggested that certain other cannabinoids like CBD may also play a significant role in its psychoactive effects.[8][51][52]




Medical use
Main article: Medical cannabis
Although the extent of the medicinal value of cannabis has been debated, it does have several well-documented beneficial effects. Among these are: the amelioration of nausea and vomiting, stimulation of hunger in chemotherapy and AIDS patients, lowered intraocular eye pressure (shown to be effective for treating glaucoma), as well as general analgesic effects (pain reliever).b[›]

Less confirmed individual studies also have been conducted indicating cannabis to be beneficial to a gamut of conditions running from multiple sclerosis to depression. Synthesized cannabinoids are also sold as prescription drugs, including Marinol (dronabinol in the United States and Germany) and Cesamet (nabilone in Canada, Mexico, The United States and The United Kingdom).b[›]

Currently, the U.S. Food and Drug Administration (FDA) has not approved smoked marijuana for any condition or disease in the United States, largely because good quality scientific evidence for its use is lacking; however, a major barrier to acquiring the necessary evidence is the lack of federal funding for this kind of research.[53] Regardless, thirteen states have legalized cannabis for medical use.[54][55] Canada, Spain, The Netherlands and Austria have also legalized cannabis for medicinal use.[56][57]

Long-term effects
Main article: Effects of cannabis#Long-term effects
The smoking of cannabis is the most harmful method of consumption, as the inhalation of smoke from organic materials can cause various health problems.[58]

By comparison, studies on the vaporization of cannabis found that subjects were "only 40% as likely to report respiratory symptoms as users who do not vaporize, even when age, sex, cigarette use, and amount of cannabis consumed are controlled."[59] Another study found vaporizers to be "a safe and effective cannabinoid delivery system."[60][61]


Cannabis is ranked one of the least harmful drugs by a study published in the UK medical journal, The Lancet.[62]While a study in New Zealand of 79 lung-cancer patients suggested daily cannabis smokers have a 5.7 times higher risk of lung cancer than non-users,[63] another study of 2252 people in Los Angeles failed to find a correlation between the smoking of cannabis and lung, head or neck cancers.[64] These effects have been attributed to the well documented anti-tumoral properties of cannabinoids, specifically tetrahydrocannabinol (THC) and cannabidiol. Some studies have also found that moderate cannabis use may protect against head and neck cancers,[65] as well as lung cancer.[66] Some studies have shown that cannabidiol may also be useful in treating breast cancer.[67]

Cannabis use has been assessed by several studies to be correlated with the development of anxiety, psychosis, and depression.[68][69] Indeed, a 2007 meta-analysis estimated that cannabis use is statistically associated, in a dose-dependent manner, to an increased risk in the development of psychotic disorders, including schizophrenia.[70] No causal mechanism has been proven, however, and the meaning of the correlation and its direction is a subject of debate that has not been resolved in the scientific community. Some studies assess that the causality is more likely to involve a path from cannabis use to psychotic symptoms rather than a path from psychotic symptoms to cannabis use,[71] while others assess the opposite direction of the causality, or hold cannabis to only form parts of a "causal constellation", while not inflicting mental health problems that would not have occurred in the absence of the cannabis use.[72][73]

Though cannabis use has at times been associated with stroke, there is no firmly established link, and potential mechanisms are unknown.[74] Similarly, there is no established relationship between cannabis use and heart disease, including exacerbation of cases of existing heart disease.[75] Though some fMRI studies have shown changes in neurological function in long term heavy cannabis users, no long term behavioral effects after abstinence have been linked to these changes.[76]

Adulterants
Adulterants in cannabis are less common than in other drugs of abuse. Chalk (in the Netherlands) and glass particles (in the UK) have been used at times to make cannabis appear to be higher quality.[77][78][79] Increasing the weight of hashish products in Germany with lead caused lead intoxication in at least 29 users.[80] In the Netherlands two chemical analogs of Sildenafil (Viagra) were found in adulterated marijuana.[81]

Gateway drug theory
Further information: Gateway drug theory
Some claim that trying cannabis increases the probability that users will eventually use "harder" drugs. This hypothesis has been one of the central pillars of anti-cannabis drug policy in the United States,[82] though the validity and implications of these hypotheses are highly debated.[83] Studies have shown that tobacco smoking is a better predictor of concurrent illicit hard drug use than smoking cannabis.[84]

No widely accepted study has ever demonstrated a cause-and-effect relationship between the use of cannabis and the later use of harder drugs like heroin and cocaine. However, the prevalence of tobacco cigarette advertising and the practice of mixing tobacco and cannabis together in a single large joint, common in Europe, are believed to be a factor in promoting nicotine dependency among young persons investigating cannabis.[85]

A 2005 comprehensive review of the literature on the cannabis gateway hypothesis found that pre-existing traits may predispose users to addiction in general, the availability of multiple drugs in a given setting confounds predictive patterns in their usage, and drug sub-cultures are more influential than cannabis itself. The study called for further research on "social context, individual characteristics, and drug effects" to discover the actual relationships between cannabis and the use of other drugs.[86]

A new user of cannabis who feels there is a difference between anti-drug information and their own experiences will apply this distrust to public information about other, more powerful drugs. Some studies state that while there is no proof for this gateway hypothesis, young cannabis users should still be considered as a risk group for intervention programs.[87] Other findings indicate that hard drug users are likely to be "poly-drug" users, and that interventions must address the use of multiple drugs instead of a single hard drug.[88]

Another gateway hypothesis is that while cannabis is not as harmful or addictive as other drugs, a gateway effect may be detected as a result of the "common factors" involved with using any illegal drug. Because of its illegal status, cannabis users are more likely to be in situations which allow them to become acquainted with people who use and sell other illegal drugs.[89][90] By this argument, some studies have shown that alcohol and tobacco may be regarded as gateway drugs.[84] However, a more parsimonious explanation could be that cannabis is simply more readily available (and at an earlier age) than illegal hard drugs, and alcohol/tobacco are in turn easier to obtain earlier than cannabis (though the reverse may be true in some areas), thus leading to the "gateway sequence" in those people who are most likely to experiment with any drug offered.[83]

Legal status

Cannabis propaganda sheet from 1935Main article: Legality of cannabis
See also: Drug prohibition, Drug liberalization, and AB 390
Since the beginning of the 20th century, most countries have enacted laws against the cultivation, possession, or transfer of cannabis for recreational use. These laws have impacted adversely on the cannabis plant's cultivation for non-recreational purposes, but there are many regions where, under certain circumstances, handling of cannabis is legal or licensed. Many jurisdictions have lessened the penalties for possession of small quantities of cannabis, so that it is punished by confiscation and sometimes a fine, rather than imprisonment, focusing more on those who traffic the drug on the black market.

In some areas where cannabis use has been historically tolerated, some new restrictions have been put in place, such as the closing of cannabis coffee shops near the borders of the Netherlands,[91] closing of coffee shops near secondary schools in the Netherlands and crackdowns on "Pusher Street" in Christiania, Copenhagen in 2004.[92][93]

Some jurisdictions use free voluntary treatment programs and/or mandatory treatment programs for frequent known users. Simple possession can carry long prison terms in some countries, particularly in East Asia, where the sale of cannabis may lead to a sentence of life in prison or even execution.

Price
The price or street value of cannabis varies strongly by region and area. In addition, some dealers may sell potent buds at a higher price.[94]

In the United States, cannabis is overall the #4 value crop, and is #1 or #2 in many states including California, New York and Florida, averaging $3,000/lb.[95][96] It is believed to generate an estimated $36 billion market.[97] Most of the money is spent not on growing and producing but on smuggling the supply to buyers. The United Nations Office on Drugs and Crime claims in its 2008 World Drug Report that typical U.S. retail prices are 10-15 dollars per gram (approximately $290 to $430 per ounce). Street prices in North America are known to range at about $150 to $250 per ounce.[98]

The European Monitoring Centre for Drugs and Drug Addiction reports that typical retail prices in Europe for cannabis varies from 2€ to 14€ per gram, with a majority of European countries reporting prices in the range 4–10€.[99] In the United Kingdom, a cannabis plant has an approximate street value of £300.[100]

Truth serum
Cannabis was used as a truth serum by the Office of Strategic Services (OSS), a US government intelligence agency formed during World War II. In the early 1940s, it was the most effective truth drug developed at the OSS labs at St. Elizabeths Hospital; it caused a subject "to be loquacious and free in his impartation of information."[101]

In May 1943, Major George Hunter White, head of OSS counter-intelligence operations in the US, arranged a meeting with Augusto Del Gracio, an enforcer for gangster Lucky Luciano. Del Gracio was given cigarettes spiked with THC concentrate from cannabis, and subsequently talked openly about Luciano's heroin operation. On a second occasion the dosage was increased such that Del Gracio passed out for two hours.[101]

Breeding and cultivation

Maturing female Cannabis plantMain article: Cannabis cultivation
It is often claimed by growers and breeders of herbal cannabis that advances in breeding and cultivation techniques have increased the potency of cannabis since the late 1960s and early '70s, when THC was first discovered and understood. However, potent seedless marijuana such as "Thai sticks" were already available at that time. Sinsemilla (Spanish for "without seed") is the dried, seedless inflorescences of female cannabis plants. Because THC production drops off once pollination occurs, the male plants (which produce little THC themselves) are eliminated before they shed pollen to prevent pollination. Advanced cultivation techniques such as hydroponics, cloning, high-intensity artificial lighting, and the sea of green method are frequently employed as a response (in part) to prohibition enforcement efforts that make outdoor cultivation more risky. These intensive horticultural techniques have made it possible to grow strains with fewer seeds and higher potency. It is often cited that the average levels of THC in cannabis sold in United States rose dramatically between the 1970s and 2000, but such statements are likely skewed because of undue weight given to much more expensive and potent, but less prevalent samples.[102]


"Skunk" refers to several named strains of potent cannabis, grown through selective breeding and often hydroponics. It is a cross-breed of Cannabis sativa and C. indica (although other strains of this mix exist in abundance). Skunk cannabis potency ranges usually from 6% to 15% and rarely as high as 20%. The average THC level in coffee shops in the Netherlands is about 18–19%.[103]

Skunk can sometimes be incorrectly mistaken for all types of female herbal cannabis.[104]

After revisions to cannabis rescheduling in the UK, the government moved cannabis back from a class C to a class B drug. A purported reason was the appearance of high potency cannabis.[105]

It is noted that one of the earliest strains of skunk to appear was that of "SKUNK #1", which has been inbred since 1978.[106] High potency herbal cannabis has been around potentially, even longer.

A Dutch double-blind, randomized, placebo-controlled, cross-over study examining male volunteers aged 18–45 years with a self-reported history of regular cannabis use concluded that smoking of cannabis with high THC levels (marijuana with 9–23% THC), as currently sold in coffee shops in the Netherlands, may lead to higher THC blood-serum concentrations. This is reflected by an increase of the occurrence of impaired psychomotor skills, particularly among younger or inexperienced cannabis smokers, who do not adapt their smoking style to the higher THC content.[107] High THC concentrations in cannabis was associated with a dose-related increase of physical effects (such as increase of heart rate, and decrease of blood pressure) and psychomotor effects (such as reacting more slowly, being less concentrated, making more mistakes during performance testing, having less motor control, and experiencing drowsiness). It was also observed during the study that the effects from a single joint at times lasted for more than eight hours. Reaction times remained impaired five hours after smoking, when the THC serum concentrations were significantly reduced, but still present. The researchers suggested that THC may accumulate in blood-serum when cannabis is smoked several times per day.

Another study showed that consumption of 15 mg of Δ9-THC resulted in no impairment to learning whatsoever occurring over a three-trial selective reminding task after two hours. In several tasks, Δ9-THC increased both speed and error rates, reflecting “riskier” speed–accuracy trade-offs.